7K of USA

Colorado_Outback

Adventurer
Its been a long winter, hard to get much done without a space big enough to pull this thing all the way in. That's soon about to change as our new shop is almost complete!
Ill be ordering a new motor from Summit next week-
http://www.summitracing.com/parts/nal-12568758/overview/
And installing all new steering parts that ive had on the shelf for 5mos once I can get it into the new shop. Hoping to have it ready to rock for the summer by mid May.

Being able to come here and check out all the builds that are getting winter attention makes some of the long winter work weeks a little more bearable!
 

Colorado_Outback

Adventurer
Well.. I had a plan.. then this L18 8.1L 496 came into my life. Looks like ill be following in Larrys footsteps, lucky for me he's figured out all the hard stuff all ready!

Its got a couple obvious issues, but if it actually has 84K as advertised I think I did ok. It supposedly came out of a 2005 Top Kick 5500. It has the fleet/marine pan, extended oil fill, down ward exiting exhaust manifolds and medium duty accessory setup. Also still has the Allison adapter and flexplate.

20150329_154831 by colorado_baja, on Flickr

20150329_154844 by colorado_baja, on Flickr

20150329_154820 by colorado_baja, on Flickr

Needs the marine pan swapped for a truck oil pan, extended oil fill swapped out, dip stick tube is bent, 2 rear coils are damaged. Extended AC lines, swap the dbw TB for a mechanical 454 TB, and swap the exhaust manifolds for a tuck set. Adapt or cap oil cooler lines, and figure out how to connect the fuel.
That's all the major hurdles I can think of off the top of my head. The rest is just shelling out $$ for the Howell harness/ecu and other off the shelf parts.. Oh and turning a lot of wrenches :sombrero:

9035352227_9ea849c8a2_c.jpg


From Larrys L18 8.1L swap info thread on CK5, anyone interested in doing this swap should start reading here:
http://coloradok5.com/forums/showthread.php?t=308019
 
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Colorado_Outback

Adventurer
Took a peek inside, huge relief to not see a pound of sludge and dirt. Looks like an 84K mile motor to me, Ill probably do a leak down before I put it in just for extra peace of mind.
20150330_150819 by colorado_baja, on Flickr

Ordered the new dipstick and tube and the oil fill parts, also found a set of suburban exhaust manifolds and got those on the way.
Need to locate a truck oil pan and order a ton of parts.
 

Larry

Bigassgas Explorer
Nice score! A power wash and fresh paint and you’ll be all set! You have a lot of work ahead of you but it will be totally worthwhile when it is done. The engine you got looks like a 2003 due to the bare aluminum valve covers but with return type fuel fail. 2002 had painted valve covers and 2004 and later had returnless fuel rails. The other nice thing you have is the medium duty ZF power steering pump! Nice! Bummer they cut the fuel line though. It is unlikely the exhaust manifolds will fit your truck but you could use any BBC exhaust manifold or header on an 8.1L. The best manifold to use would be a period correct GMT400 454 manifold and it just so happens I have the Napa part numbers for those (6002460 LH / 6002461 RH. Cost about $125 each). I also happen to have an extra pick-up truck oil pan (no sump though) if you want to trade for what you have. I would also be interested in your exhaust manifolds. Heck, I may have some BBC manifolds in my hoard that will fit your truck but they would need broken studs extracted and probably resurfaced to make them flat again. It’s possible the 8.1L manifolds that came on my engines may fit your frame rails too.

Looking at your plan, here are a couple part numbers you will need. Manual trans flywheel 12582964, flywheel to crank shaft bolts 2563485 x6, 8.1L specific pilot bearing 6302VSP43 (Napa). Your existing clutch and pressure plate should fit the 8.1L flywheel however you may need to open the holes the pressure plate to allow for the larger 10mm pressure plate to flywheel bolts to pass. The pressure plate to flywheel bolt part number is 12561465 x 7.

The only other thing I can see is you that may want to consider swapping is the alternator as the one you have looks to be the ECM controlled alternator regulator. On my 8.1L swaps I prefer to not have the ECM control the alternator and use late 90’s CS-144 alternators. The Napa part number for a 140 AMP CS-144 is 2134644. With that you will need to find a special serp belt too as the alternator body is larger and requires a longer belt (the CS does fit your brackets tho!). Mine run 6K1030 serp belts but you may need to go to a 6K1035, 40, 45…etc. being you have a different p/s pump that may have a different mounting location than the lighter Saginaw pumps. Lastly, replace the crank sensor before you install the engine. Crank sensors on early engines are the #1 item to fail…..and you sure don’t want to replace that sucker once it is in the truck. Don’t ask me why I know that. LOL The GM part number for the crank sensor is 12575172.

Good luck! Let me know if you need anything.
 

Colorado_Outback

Adventurer
Just....really cool. That's all I can say!

Thanks Seabass! This is my first legit swap so I'm learning new things every day haha.

Your truck brings back a lot of memories, a friends dad had that exact truck down to the year and trim when I was in high school. Spent a lot of time riding in the bed to duck blinds and pheasant fields.

Ran into my first unexpected expense on this project today. My engine stand, ole yeller just wasn't up to the task of holding up this motor so I ran down to Harbor Freight and got a 2000lb stand. It was my lucky day, they had an open box one so I saved 50 bucks off the top.
20150403_111055 by colorado_baja, on Flickr

A lot less wet noodle action on this one!

20150403_115440 by colorado_baja, on Flickr


Found someone to trade me exhaust manifolds for my medium duty manifolds so I guess technically I'm still in the black since I would have spent a couple hundred acquiring them:)
 
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Colorado_Outback

Adventurer
Nice score! A power wash and fresh paint and you'll be all set! You have a lot of work ahead of you but it will be totally worthwhile when it is done. The engine you got looks like a 2003 due to the bare aluminum valve covers but with return type fuel fail. 2002 had painted valve covers and 2004 and later had returnless fuel rails. The other nice thing you have is the medium duty ZF power steering pump! Nice! Bummer they cut the fuel line though. It is unlikely the exhaust manifolds will fit your truck but you could use any BBC exhaust manifold or header on an 8.1L. The best manifold to use would be a period correct GMT400 454 manifold and it just so happens I have the Napa part numbers for those (6002460 LH / 6002461 RH. Cost about $125 each). I also happen to have an extra pick-up truck oil pan (no sump though) if you want to trade for what you have. I would also be interested in your exhaust manifolds. Heck, I may have some BBC manifolds in my hoard that will fit your truck but they would need broken studs extracted and probably resurfaced to make them flat again. It's possible the 8.1L manifolds that came on my engines may fit your frame rails too.

Looking at your plan, here are a couple part numbers you will need. Manual trans flywheel 12582964, flywheel to crank shaft bolts 2563485 x6, 8.1L specific pilot bearing 6302VSP43 (Napa). Your existing clutch and pressure plate should fit the 8.1L flywheel however you may need to open the holes the pressure plate to allow for the larger 10mm pressure plate to flywheel bolts to pass. The pressure plate to flywheel bolt part number is 12561465 x 7.

The only other thing I can see is you that may want to consider swapping is the alternator as the one you have looks to be the ECM controlled alternator regulator. On my 8.1L swaps I prefer to not have the ECM control the alternator and use late 90's CS-144 alternators. The Napa part number for a 140 AMP CS-144 is 2134644. With that you will need to find a special serp belt too as the alternator body is larger and requires a longer belt (the CS does fit your brackets tho!). Mine run 6K1030 serp belts but you may need to go to a 6K1035, 40, 45…etc. being you have a different p/s pump that may have a different mounting location than the lighter Saginaw pumps. Lastly, replace the crank sensor before you install the engine. Crank sensors on early engines are the #1 item to fail…..and you sure don't want to replace that sucker once it is in the truck. Don't ask me why I know that. LOL The GM part number for the crank sensor is 12575172.

Good luck! Let me know if you need anything.

Hey Larry,

Thanks for all the part numbers and advice! I believe this one to be an 05, its supposed to be from a Kodiak. Kodiak/Topkick didn't go return less until 06. EDIT: No EGR on this motor either. I was hoping to find the vin on the engine somewhere to verify but no luck so far. Ill have to do some research and see if I have the later cam sensor as Ive read that the 01-03? style isnt available anymore.
In any case I think I got a good one, I have about half into it what a new TBI 350 would have cost so I think I'm doing OK.

It is a bummer that they cut the fuel lines, at least they did it on the line side on this one. I plan on using compression fittings where those flex lines connect to the rails to adapt to an AN style fitting. Still have to double check but I'm pretty sure my TBI has a return so I think it will all work out.

Reusing the power steering pump will depend on if they messed it up when they clipped that line really close to the pump, they weren't very careful when they pulled the motor. And if adapting it to my hydroboost setup will be a pita or what.. Might just be easier to swap on the Saginaw.

I'm definitely interested in the truck pan you have. Unfortunately I just sent the manifolds to a guy up in WA yesterday in exchange for a set of Truck/sub manifolds. Shoot me a PM on the pan swap, it wont let me PM you for some reason.

Another thread ive been doing a lot of reading in is this guys 97 Tahoe swap:
http://www.pacificp.com/forum/viewtopic.php?t=11471&postdays=0&postorder=asc&start=220

The frame fitment should be the same as my truck, 8.1L truck manifolds look like they clear OK..
IMG_0691.jpg


I'm sure ill have to mod the Y pipe to get it to meet up with the new manifolds, hopefully the single 3"? is going to breathe enough for this motor..

Only question I can think of for you off the top of my head is, do you know a centerforce part number that will fit the 8.1L flywheel with out mods? I cant find a part number for the 8.1L on the centerforce site. I figure with the amount of TQ this motor is capable of with simple mods it will be money well spent.

Thanks again!
 
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Larry

Bigassgas Explorer
That would be odd that Medium Duty was late due to changes in Federal Regulations related to evaporative emissions that drove the change to returnless fuel system in 2004 (all manufacturers went to returnless in 2004). The company I work for had to move to returnless in 2004 on our 8.1Ls as well and our GVWR went from 12K to 26K which was actually higher than most GM Medium Duty gasoline chassis. It would surprise me that medium duty changed later to return type, unless the truck had a RPO code for alternative fuel prep or something that gave them a variance. Either way, be glad you have the return type fuel rail. That makes life much easier for you.

That is correct, there is only one crank sensor now and it supersedes the old part numbers. You can tell the new design from the old by the number of O-rings on the sensor. If the sensor has an o-ring at the top and another at the bottom it is the early one. The later sensors only have an o-ring at the top of the sensor. Most early design sensors failed early on and have been long since replaced. None the less, I would still install a new sensor now even if you have a later design. Believe me, you do NOT want to replace that sensor down the road after the engine is in the truck. And when you get a new one, get a GM sensor only. Don’t trust any dime store china’s finest parts for that circuit.

Your Saginaw p/s pump probably won’t fit that bracket. The ZF brackets have different mounting holes but give it a shot. ZF pumps are great if you can make it work.

No problem on your manifolds. I actually have two new sets of 8.1L truck manifolds that are take offs and a pile of old BBC manifolds. Your frame is probably wide enough to use stock 8.1L manifolds. One bad thing about stock 8.1L manifolds is they have flat flanges and habitually leak like a header flange gasket. The older BBC manifolds are tapered for use with an exhaust donut. Too bad I didn’t notice your thread sooner or I could have saved you some money and freight. Looks like my PM box was full. I cleaned it out so it should work now. The left over pan I have is loose and ready to fly but it needs a date with a solvent tank.

Yeah, I watched that Tahoe swap take place for a couple years and help him here and there. It turned out pretty nice although not the same approach I would have taken on many things but with him being in CA probably dictated what he had to do for emissions reasons for a CARB referee.

The Centerforce I use in the K10 and Burb behind the 8.1Ls is a DF024909. My trucks are basically set up just like yours with an external clutch slave cylinder. I don’t see why that part number wouldn’t work for yours too but like I mentioned above…..you will need to open the holes in the pressure plate to 10MM for the pressure plate to flywheel bolts to pass. The dowel pins in the 8.1L flywheel will also need to be removed. That part number has lived up very well behind the 8.1L and the 454HO that was in it prior. It also has a nice and soft pedal feel. The price of it bites though
 

Colorado_Outback

Adventurer
Well now I'm just too curious for my own good haha.

I pulled the crank sensor and its a later version with a single o-ring at the top. Cam sensor part number is 12568983, I believe that is the 04 and up CPS.

The only other reason I think its an 05 is the 2006 model year summary lists Returnless fuel system as new for Kodiak/Topkick.

2006 model year summary

• Increase to 325 horsepower for Chevrolet Suburban, Avalanche and GMC Yukon XL
• New dual mid-coupled converter system
• Returnless fuel injection for Chevrolet Kodiak and GMC TopKick
• Improved electronic throttle control pedal and throttle actuator control (TAC) module
• Recalibrated P59 engine controller

Its an odd one for sure, lucky for me it has the best of all variants for my swap situation.

Ill definitely swap a new crank sensor before I put it together I was thinking what a nightmare that would be in the truck while looking at the motor the other day haha.

Ill also definitely think on the manifolds, I'm with you.. flat flanges suck. I would rather have a doughnut gasket any day. I swapped the guy straight across so im only out shipping for my set. Just trying to keep costs low for now, I know there are still a couple unknowns that will ultimately have to be solved with $$.

Thanks for the Centerforce number, the price is a little harsh but I don't mind paying a little if it will save me from pulling the trans sooner rather than later to swap a burnt clutch.
 

Larry

Bigassgas Explorer
Well now I'm just too curious for my own good haha.

I pulled the crank sensor and its a later version with a single o-ring at the top. Cam sensor part number is 12568983, I believe that is the 04 and up CPS.

The only other reason I think its an 05 is the 2006 model year summary lists Returnless fuel system as new for Kodiak/Topkick.

2006 model year summary

• Increase to 325 horsepower for Chevrolet Suburban, Avalanche and GMC Yukon XL
• New dual mid-coupled converter system
• Returnless fuel injection for Chevrolet Kodiak and GMC TopKick
• Improved electronic throttle control pedal and throttle actuator control (TAC) module
• Recalibrated P59 engine controller

Its an odd one for sure, lucky for me it has the best of all variants for my swap situation.

Ill definitely swap a new crank sensor before I put it together I was thinking what a nightmare that would be in the truck while looking at the motor the other day haha.

Ill also definitely think on the manifolds, I'm with you.. flat flanges suck. I would rather have a doughnut gasket any day. I swapped the guy straight across so im only out shipping for my set. Just trying to keep costs low for now, I know there are still a couple unknowns that will ultimately have to be solved with $$.

Thanks for the Centerforce number, the price is a little harsh but I don't mind paying a little if it will save me from pulling the trans sooner rather than later to swap a burnt clutch.


You’re right, somehow I missed that one in my GM Powertrain model year summary stash. Looks like 2004 was the main year for returnless in trucks, SUVs and Workhorse then Marine got it in 2005 and Medium Duty got it in 2006. The weird thing is Workhorse used the medium duty engine assembly part number so I had it in my head they all went returnless in 2004. Odd, as the big Fed EVAP change was for 2004 Model Year. Good reminder of what happened when. Good catch!



Vortec 8100 8.1L V-8 (L18)
2004 Model Year Summary

• Returnless fuel injection for Chevrolet Avalanche, Silverado and Suburban, GMC Sierra and Yukon XL and Workhorse Custom Chassis
• Low permeability intake manifold body gaskets
• Improved onboard refueling vapor recovery (ORVR) system for Avalanche, Silverado, Suburban, Sierra and Yukon XL
• Exhaust gas recirculation (EGR) eliminated
• Improved crank and cam timing sensors
• Improved crankshaft seal
• Adjustable throttle pedal for Workhorse Custom Chassis
• Revised cylinder heads for industrial applications


FULL DESCRIPTIONS OF NEW OR CHANGED FEATURES

RETURNLESS FUEL INJECTION FOR CHEVROLET AVALANCHE, SILVERADO AND SUBURBAN, GMC SIERRA AND YUKON XL AND WORKHORSE CUSTOM CHASSIS
All Vortec 8100s built for these applications are equipped with a new "returnless" fuel injection system that eliminates fuel return lines between the engine and the gasoline tank. The new fuel system is also known as a demand system.

Before model year 2004, the Vortec 8100’s sequential fuel injection (SFI) used a return line to manage fuel pressure by bleeding off excess fuel at the fuel rail and returning the excess to the tank. The new system eliminates the return lines and moves the fuel-pressure regulator from the fuel rail on the engine to the fuel tank. The fuel line from the tank now includes pulse dampeners, or a series of baffles, that manage fuel pulsing and limit noise.

Because it delivers only the amount of fuel need by the injectors, and returns no fuel to the gas tank, the returnless system essentially eliminates heat transfer from the engine to tank. This reduces the amount of vapor generated in the tank, and captured by the evaporative emissions control system.

Vortec 8100s built for the medium-duty Chevrolet Kodiak and GMC Topkick, as well as those built for marine and industrial applications, continue with fuel injection managed with return lines.

LOW PERMEABILITY INTAKE MANIFOLD AND THROTTLE BODY GASKETS
The Vortec 8100 has new intake manifold sealing gaskets manufactured from a fluorocarbon material. These fluorocarbon gaskets represent the best sealing technology available. The gaskets are resistant to most chemicals, for maximum durability, and particularly impermeable to small hydrocarbon molecules. Gasoline vapor cannot penetrate the fluorocarbon. Moreover, the gaskets are designed to improve sealing for the life of the engine. They are molded with slight protrusions, or ``snouts,’’ that fit into counter-bores milled in the cylinder heads. The snouts more positively locate the gaskets and virtually eliminate the possibility of movement during assembly or after repeated thermal cycling over the life of the engine.

IMPROVED ONBOARD REFUELING VAPOR RECOVERY (ORVR) SYSTEM FOR CHEVROLET AVALANCHE AND SILVERADO, GMC SIERRA AND YUKON XL
The ORVR system on these Vortec 8100-equipped vehicles uses a new evaporative emissions canister and purge-control solenoid. ORVR reduces evaporative emissions by preventing gasoline vapor from escaping into the atmosphere during refueling. These new ORVR components take full advantage of advanced technology built into the Vortec 8100's P59 Powertrain Control Module (PCM). The PCM and new components more efficiently manage ORVR, and improve the accuracy and robustness of the OBDII (On-Board Diagnostics) system.


Vortec 8100 8.1L V-8 (L18)
2005 Model Year Summary


• New for Chevrolet Kodiak and GMC TopKick with four-wheel drive
• Floating pin pistons
• Returnless fuel injection for marine applications
• Improved oil pan (for medium duty applications)
• Improved throttle actuator control module
• Rate-based diagnostics
• GF-4 engine oil

FULL DESCRIPTIONS OF NEW OR CHANGED FEATURES

NEW FOR CHEVROLET KODIAK AND GMC TOPKICK WITH FOUR-WHEEL DRIVE
For 2005, the Vortec 8100 will be available in Chevrolet Kodiak and GMC Topkick medium-duty trucks with four-wheel drive. Vortec 8100s built for this application require packaging adjustments to accommodate a front transaxle, including exhaust manifolds, heat shields and starter motor.

FLOATING PIN PISTONS
The Vortec 8100 is fitted with new floating-pin pistons. Introduced previously on GM Powertrain’s Vortec 6000 V-8, these pistons feature wrist pins that “float” inside the rod bushing and the pin bores in the piston barrel. Previously, the Vortec 8100 used a fixed-pin assembly, in which the connecting rod is fixed to the piston’s wrist pin, and the pin rotates in the pin bore. In the Vortec 8100, snap rings now retain the wrist pin in the piston, while the rod moves laterally on a bushing around the pin.

The Vortec 8100’s pistons, piston rings and connecting rods are identical to those used in 2004. The new floating-pin assembly allows tighter pin to pin-bore tolerances and reduces noise generated during engine operation.

RETURNLESS FUEL INJECTION FOR MARINE APPLICATIONS
All Vortec 8100s built for marine application are equipped with a new ``returnless’’ fuel injection system that eliminates fuel return lines between the engine and the gasoline tank. The new fuel system is also known as a demand system, and was introduced on Vortec 8100s built for the Chevrolet Silverado and GMC Sierra for model year 2004.

Before model year 2004, the sequential fuel injection (SFI) on all Vortec 8100s used a return line to manage fuel pressure by bleeding off excess fuel at the fuel rail and returning the excess to the tank. The new system eliminates the return lines and moves the fuel pressure regulator from the fuel rail on the engine to the fuel tank. The fuel line from the tank now includes pulse dampeners, or a series of baffles, that manage fuel pulsing and limit noise.

Because it delivers only the amount of fuel need by the injectors, and returns no fuel to the gas tank, the returnless system essentially eliminates heat transfer from the engine to tank. This reduces the amount of vapor generated in the tank and released as evaporation. The returnless system has been introduced on marine engines to give marine customers the same emissions standards and efficient operation as truck customers.

IMPROVED OIL PAN FOR MEDIUM DUTY AND MARINE APPLICATIONS
The oil pan on Vortec 8100s built for medium-duty (C4-C8 trucks) and marine use has been redesigned. This cast aluminum oil pan is essentially identical for both applications, with differences limited to final machining.

With the new pan, the interior baffle has been reconfigured to maximize oil flow, improve durability and stiffen the cast-aluminum pan’s structure, further reducing engine vibration. Moreover, sump capacity for medium-duty trucks increases 3.1 liters. The change was driven by the demands of the commercial fleet and rental markets. Rental truck customers may not be the most diligent operators when it comes to monitoring oil levels. The larger sump adds an extra measure of security for rental companies and fleet operators, even if customers use trucks for weeks without checking oil levels.

IMPROVED THROTTLE ACTUATOR CONTROL MODULE
All Vortec 8100’s are equipped with an improved throttle actuator control (TAC) module. Located on the throttle body, the TAC module is an integral component of the Vortec 8100’s electronic throttle control (ETC) system. The TAC takes command from the powertrain control module (PCM) and then operates the motor that opens and closes the throttle plate.

The TAC module has new read-only memory and control software. Like its predecessor, it allows multiple throttle progressions or algorithms, which operate the throttle at varying rates according to operating conditions and driver demands. It also has built-in default settings that protect the engine and ensure safe operation in the event of malfunction with the ETC or other engine subsystems.

RATE-BASED DIAGNOSTICS
The Vortec 8100’s powertrain control module (PCM) uses a new monitoring protocol known as rate-based diagnostics. Rate-based diagnostics improve the robustness of the Onboard Diagnostics System (OBD II) and ensure optimal performance of emissions control systems.

With rate-based diagnostics, the PCM applies a new formula to manage OBD II. Essentially, new software increases the frequency at which the PCM checks various engine systems, and particularly emissions-control systems such as the catalytic converter, oxygen sensors and exhaust gas recirculation (EGR). Rate-based diagnostics more reliably monitor real-word operation of these systems, and allow regulatory agencies to more easily measure and certify emissions compliance. The new protocol allows the Vortec 8100 to meet more stringent OBD II requirements two years ahead of a mandate by the California Air Resources Board.

GF-4 ENGINE OIL
All Vortec 8100s will be shipped to customers with a new engine oil that reduces engine deposits, extends oil change intervals, improves fuel economy and extends the life of emissions control systems. GM Powertrain has taken a leading role in developing and introducing the new oil, designated GF-4 (for “Gasoline Fueled, Standard 4’’) by the American Petroleum Institute.

GF-4 contains a new ash-free antioxidant ingredient and less phosphorous than the previous formulation (GF-3). The typical automotive engine now operates at a much higher temperature than an engine built 10 years ago. GF-4 is twice as resistant to oxidizing, which can present itself as foaming, at high operating temperatures. At the same time, GF-4 provides better low-temperature protection, reducing engine wear during the critical cold-start period. Lower phosphorus and sulfur content – chemicals that are harmful to catalytic converters – will extend anticipated catalyst life beyond 120,000 miles. Finally, GF-4 lowers friction overall and retains its optimal friction-reducing characteristics longer. The result is an anticipated improvement of 0.2 percent to 0.3 percent in an engine’s fuel economy, and longer oil change intervals.

Production of Vortec 8100s with GF-4 begin in fall 2004, ahead of an industry recommendation of April 30, 2005. This will allow vehicles with the Vortec 8100 to be tested for 2005 Corporate Average Fuel Economy (CAFE) standards with GF-4. GM’s industry-leading Oil Life System may be adjusted to account for the new oil. The owner’s manual in vehicles equipped with the Vortec 8100 will continue to recommend oil with the Starburst logo, which must be certified to GF-4 by May 2005.

OVERVIEW

Few words generate excitement for car and truck enthusiasts like ‘’Big Block.’’ The Vortec 8100 V-8 is the legendary GM Big Block for a new millennium, with a longer expected useful life and horsepower and torque that surpass the large displacement gasoline engines offered in competitors’ heavy-duty pickups. This heavy-duty engine also sets benchmarks for marine and industrial application worldwide.

Introduced in the 2001 Chevrolet Silverado and Suburban and GMC Sierra and Yukon XL, the Vortec 8100 was essentially a new engine. Nearly 90 percent of its parts have been completely redesigned. While it shares its valve centers, bore centers and bore diameter with the previous 7.4L Big Block, stroke was increased 9.4 mm (.37 inch) to increase displacement 700 cc. The latest math-based engineering tools were used to improve the flow and distribution of oil and coolant, to refine castings and to improve production quality and efficiency.

After extensive analysis of competitors' engines, the Vortec 8100 development team set a goal of 200,000 miles of useful life without major repairs – and then achieved it. Before it was ready for production, this big block had to pass the “Marine Dock'' test, in which it is run at full throttle for 300 consecutive hours without a failure, and a minimum of 1,000 hours at full-throttle operation for truck applications.

In the four years since its launch, virtually every aspect of the engine – from sealing to electronic management to noise, vibration and harshness control – has been re-examined and improved. For 2004, Vortec 8100s built for truck installation were equipped with a new returnless fuel injection system that eliminated fuel return lines between the engine and the gasoline tank and reduced evaporative emissions. Combined with new intake manifold and throttle body gaskets, manufactured of an advanced fluorocarbon material that is virtually impermeable to hydrocarbon molecules, the returnless fuel system allows the Vortec 8100 to meet near-zero evaporative emissions standards. Also in 2004, Vortec 8100s built for industrial applications were equipped with new valves, valve seat material and springs designed expressly for industrial operation at low, steady rpm.

GM's leadership in big-block V-8 technology dates to at least 1958, when the Vortec 8100's progenitor was launched with 348 cubic inches of displacement in the full-size 1958 Chevrolets. The 348 was followed by several variants, including a 409, 366 and 427. In 1970, the 454-cubic-inch big-block was introduced. It was retooled in 1991 as the Vortec 7400 – a truly powerful pickup engine that met stringent 1990s emission requirements. The Vortec 8100 bears little resemblance to those engines, but it maintains a tradition of outstanding durability and class-leading power.


VORTEC 8100 8.1L V-8 (L18)
2006 model year summary


• Increase to 325 horsepower for Chevrolet Suburban, Avalanche and GMC Yukon XL
• New dual mid-coupled converter system
• Returnless fuel injection for Chevrolet Kodiak and GMC TopKick
• Improved electronic throttle control pedal and throttle actuator control (TAC) module
• Recalibrated P59 engine controller
Full descriptions of new or changes features
Increase to 325 horsepower
For the 2006 Chevrolet Suburban, Avalanche and GMC Yukon XL 2500 Series, the Vortec 8100 delivers an additional 5 horsepower. Increased power results from reduced backpressure in the exhaust system, enabled by a new catalytic converter system. The new converter system is primarily designed to lower emissions. The Vortec 8100’s new rating is 325 horsepower and 447 lb.-ft. of torque.
New dual mid-coupled catalytic converter system
Chevrolet Suburban, Avalanche and GMC Yukon XL three-quarter-ton models equipped with the Vortec 8100 receive a new M120 mid-coupled catalytic converter system. Two new mid-coupled converters replace four previous ones (two mid-coupled and two under-floor converters). The new dual converters, with about two liters of volume, are also located closer to the exhaust manifold to enhance their effectiveness. Their construction, consisting of multiple materials, is unchanged. While providing lower LEV emissions levels, the new converter system also allows a more moderate 47.1 kPa of exhaust back pressure for more power. Induction restriction is unchanged.
Improved electronic throttle control and throttle actuator control module
With the Vortec 8100, the Chevrolet Suburban, Avalanche and GMC Yukon XL 2500 Series also receive an improved electronic throttle control pedal and improved throttle actuator control (TAC) module. The throttle pedal provides more consistent truck-to-truck pedal force and effort feel for vehicle operators. The TAC is designed to accommodate the new pedal.
Located on the engine side of the front of dash, the TAC module is an integral component of the Vortec 8100’s electronic throttle control (ETC) system. The TAC takes command from the powertrain control module (PCM) and then operates the motor that opens and closes the throttle plate.
Like its predecessor, the TAC module has read-only memory and control software. It allows multiple throttle progressions or algorithms, which operate the throttle at varying rates according to operating conditions and driver demands. It also has built-in default settings that protect the engine and ensure safe operation in the event of malfunction with the ETC or other engine subsystems.
Returnless fuel injection for Chevrolet Kodiak and GMC TopKick
For 2006, the Vortec 8100 available in Chevrolet Kodiak and GMC Topkick medium duty trucks is equipped with a new "returnless" fuel injection system that eliminates fuel return lines between the engine and the gasoline tank. The new fuel system is also known as a demand system. The system is already used with the Vortec 8100 on Chevrolet Silverado and GMC Sierra models and with all Vortec 8100s built for marine applications.
Before 2006, the Sequential Fuel Injection (SFI) in medium duty trucks equipped with the Vortec 8100 used a return line to manage fuel pressure by bleeding off excess fuel at the fuel rail and returning the excess to the fuel tank. The new system eliminates the return lines and moves the fuel-pressure regulator from the fuel rail on the engine to the fuel tank. But because the returnless system delivers only the amount of fuel needed by the injectors, and returns no fuel to the fuel tank, it eliminates heat transfer from the engine to the fuel tank. This reduces the amount of vapor generated in the tank and captured by the evaporative emissions control system.
Recalibrated P59 engine controller
The Vortec 8100’s P59 engine controller in medium duty trucks is recalibrated to coordinate with the newly available version of the Allison five-speed automatic transmission and the returnless fuel injection system. The P59 also has new calibrations to optimize driveability and fuel economy with the new Allison six-speed automatic transmission being introduced for the first time in GM full-size pickups.
Overview
Few words generate excitement for car and truck enthusiasts like ‘’Big Block.’’ The Vortec 8100 V-8 is the legendary GM Big Block for a new millennium, with a longer expected useful life and horsepower and torque that surpass the large-displacement gasoline engines offered in competitors’ heavy-duty pickups. This heavy-duty engine also sets benchmarks for marine and industrial application worldwide.
Introduced in the 2001 Chevrolet Silverado and Suburban and GMC Sierra and Yukon XL, the Vortec 8100 was essentially a new engine. Nearly 90 percent of its parts have been completely redesigned. While it shares its valve centers, bore centers and bore diameter with the previous 7.4L big block, stroke was increased 9.4 mm (.37 inch) to increase displacement 700 cc. The latest math-based engineering tools were used to improve the flow and distribution of oil and coolant, to refine castings and to improve production quality and efficiency.
After extensive analysis of competitors' engines, the Vortec 8100 development team set a goal of 200,000 miles of useful life without major repairs – and achieved it. Before it was ready for production, this big block had to pass the “Marine Dock'' test, in which it is run at full throttle for 300 consecutive hours without a failure, and a minimum of 1,000 hours at full-throttle operation for truck applications.
In the five years since its launch, virtually every aspect of the engine – from sealing to electronic management to noise, vibration and harshness control – has been re-examined and improved.
For 2005, the Vortec 8100 was made available in Chevrolet Kodiak and GMC TopKick trucks with four-wheel drive. GM’s big block was fitted with floating-pin piston rings, which allow tighter pin to pin-bore tolerances for quieter operation and increased durability. Returnless fuel injection was incorporated in all marine applications. Medium duty trucks received an improved oil pan. All Vortec 8100s received an improved throttle actuator control. Their powertrain control module began using a monitoring protocol, known as rate-based diagnostics, to increase the robustness of the Onboard Diagnostics System and optimize performance of the emissions control systems. All Vortec 8100s
began being shipped with GF-4 engine oil that reduces engine deposits, extends oil change intervals, improves fuel economy and extends the life of emissions control systems.
For 2004, Vortec 8100s built for Chevrolet Silverado and GMC Sierra pickups were equipped with a new returnless fuel injection system that eliminates fuel return lines between the engine and the gasoline tank and reduces evaporative emissions. Combined with new intake manifold and throttle body gaskets, manufactured of an advanced fluorocarbon material that is virtually impermeable to hydrocarbon molecules, the returnless fuel system allows the Vortec 8100 to meet near-zero evaporative emissions standards. Also in 2004, Vortec 8100s built for industrial applications were equipped with new valves, valve seat material and springs designed expressly for industrial operation at low, steady rpm.
GM's leadership in big block V-8 technology dates to at least 1958, when the Vortec 8100's progenitor was launched with 348 cubic inches of displacement in the full-size 1958 Chevrolets. The 348 was followed by several variants, including a 409, 366 and 427. In 1970, the 454-cubic-inch big-block was introduced. It was retooled in 1991 as the Vortec 7400 – a truly powerful pickup engine that met stringent 1990s emission requirements. The Vortec 8100 bears little resemblance to those engines, but it maintains a tradition of outstanding durability and class-leading power.
 

Colorado_Outback

Adventurer
My parts pile for the motor swap is growing daily. Slowly starting to get the motor cleaned up.

One thing I got out of the way this weekend was a complete steering rebuild it had a ton of play in all 37 of the rod ends. I had been procrastinating on doing it, luckily my main mechanic was there to help.
20150411_162039 by colorado_baja, on Flickr

20150411_154442 by colorado_baja, on Flickr

I replaced the inner and outer tie rods, steering damper, pitman arm, idler arm and the bracket, ball joints have seen some days but weren't sloppy so I left them be. Should be good for a while.

The 4wd IFS and steering is so goofy on this truck I wont be putting any more money into it. Ill be on the lookout for a junkyard 60 to rebuild after I finish up with the motor swap. After seeing what they want for a lift and the limited selection of options it sealed the deal for me.
 

Colorado_Outback

Adventurer
Went to get an alignment and ended up getting a free one haha. Dude kinda did me a favor, these knock off mirrors were constantly vibrating at speed. Ill probably go back to stock. How you knock the driver one off though.. I'm not sure.

20150420_151702 by colorado_baja, on Flickr

Been working on the motor too, threw the Taylor 10.4mm plug wires on there tonight just for grins.
Starting to look like a truck motor.
20150422_234108 by colorado_baja, on Flickr

Couple more things to order, May will be the month to get it done.
 

Colorado_Outback

Adventurer
Bartered for a Fold-a-Cover hard bed cover that a buddy had laying around a while back and finally got around to messing with it.

Its for a 99 and up GM, oddly enough they don't make one for 88-98, couple mods to the rails has it fitting pretty good. It opens from both ends and locks the tail gate in place. Pulling 4 bolts lets the panels come off, so loading the camper will be easy.
20150423_170856 by colorado_baja, on Flickr

Looking forward to the extra lockable storage.

20150424_124649 by colorado_baja, on Flickr

20150424_124915 by colorado_baja, on Flickr
 
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Colorado_Outback

Adventurer
Got new tires today, and my replacement mirrors on.

20150509_160159 by colorado_baja, on Flickr


The 265/75/16's that were on my truck were worn uneven and pretty bald on the front from the steering being slopped out. I have been on the lookout for a new set of tires and finding 4 used E rated 16's in decent shape was harder than I thought. Got a killer deal on these Bridgestones today, not the ideal tire but for the money I couldn't get it out of my pocket fast enough.
20150509_112313 by colorado_baja, on Flickr

Tempted to get a tire groover and make them into AT's :D

Couple more odds and ends for the motor and ill be ready to swap in a week or 2.
 

Colorado_Outback

Adventurer
Well I found a tire groover and decided to go after these tires, still no AT but better then they were.
20150511_153628 by colorado_baja, on Flickr

Howell harness is here and looks awesome. Unfortunately the ECU is on backorder, gonna have to call em next week and see whats up with that.
20150519_192600 by colorado_baja, on Flickr

Lots of baby steps lately, work has been sucking me in.

Going to tackle front brakes and hub assemblies this weekend, well I started doing the front brakes last weekend and broke one of the hubs so I decided to replace both along with the brake job.

I'm pretty well versed in the use of a flame wrench and 5lb hammer, Ive never seen 2 pieces of metal stuck together like that.
 

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