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LaOutbackTrail
06-05-2010, 12:05 AM
Hey guys,
So, I wont be doing a domestic truck build (per-se), but will likely put a GM motor into the truck that I do build. I am looking at a Land Rover Discovery I, a Range Rover Classic, and an FJ62 (all local to me) and need mechanical work.

I am looking at the 350TBI set up. I am wanting to set it up in the following order: reliability, fuel efficiency, power.
So, what I am looking for is some reference material or tips on how to build the motor. Which blocks, heads, cams, etc to look into?

I want to go with the TBI setup because it is slightly easier to install than the vortech motors, but is more reliable/set and forget it/ compared to the carbed motors.

Any help is appreciated guys!

hidesertwheelin
06-05-2010, 02:54 AM
A lot of the tbi motors came set up for roller cams. When you pull the intake, there should be 4 holes in the middle of the lifter valley. I believe that that indicted a roller cam block.

redthies
06-05-2010, 03:11 AM
Just make sure you bolt it into the FJ62! That is all you need to know!!!

Jnich77
06-05-2010, 02:10 PM
Rather than just a motor, buy a whole vehicle to get parts for to do the swap...its much easier and cheaper in the long run that way.

LaOutbackTrail
06-05-2010, 03:20 PM
Rather than just a motor, buy a whole vehicle to get parts for to do the swap...its much easier and cheaper in the long run that way.

Right, that was the plan, just forgot to mention it.

I will be doing that with the 7MGE swap on my 4Runner.

chasespeed
06-05-2010, 06:55 PM
For a vehicle that size, keep in mind the 4.3 V6. Good torque, and decent economy. The reason I mention that, is that there are TONS of those things out there in everything from the Sdime, to full size trucks and vans(and yes, I know the 350TBI is as well). Its slightly shorter, and my be easier to package. Its a 350 with 2 cylinders lopped off. Its roller cam(I believe from 87up(I am not 100% on that). a nice healthy RV cam, a bigger throttle body, roller rockers, and some headers, and thats a healthy engine, that is still reliable. I had one of these that I put 100k on w/o a problem. Never felt as if it was lacking power.

But, I would go the same route with the V8. They already have good torque, so, some simple things to reduce heat, and friction, and make it breathe just a little better, would be as far as I go to stay reliable.

A remote oil filter, with an oil cooler is a great idea.

The engines with the "centerbolt" valve covers have better breathing than the previous design, and of course the Vortec heads are even better.
If you shop carefully, there was a crossover year, some engines had the Vortec Heads, and TBI. The TBI while not being IDEAL, is simple, and reliable. Much less electrical to go wrong, and install. Either way, its a good idea.

You could also look into finding a 4bt Cummins. While heavy, can be tuned for a nice easy power 250-300 w/o a problem, tons of torque, and 20-30 MPG. PLUS, its all mechanical.

Just adding thoughts, and though I am sure if you wanted to go that route, you would have mentioned it...

Chase

Metcalf
06-05-2010, 10:47 PM
Dollar for Dollar I would have to recommend the newer 5.3 GM motors in the lsx family. They are very affordable, easy to install, make great power, and are very easy to find. They are also fairly easy to find with lower miles so you don't need to rebuild them. Any standard GM 90 degree bellhousing will bolt up with very few modifications...generally just the correct flywheel or flexplate spacing.

jp0863
06-07-2010, 01:22 AM
Check out 1Legs build, he's doing a tbi motor built up just a tad. Also www.tbichips.com has good write ups with dyno results for some of it.

evldave
06-07-2010, 05:28 PM
Hey guys,
So, I wont be doing a domestic truck build (per-se), but will likely put a GM motor into the truck that I do build. I am looking at a Land Rover Discovery I, a Range Rover Classic, and an FJ62 (all local to me) and need mechanical work.

I am looking at the 350TBI set up. I am wanting to set it up in the following order: reliability, fuel efficiency, power.
So, what I am looking for is some reference material or tips on how to build the motor. Which blocks, heads, cams, etc to look into?

I want to go with the TBI setup because it is slightly easier to install than the vortech motors, but is more reliable/set and forget it/ compared to the carbed motors.

Any help is appreciated guys!

I think this is a great idea, simple motor, not carb'd, easy to work on, and very common.

I had an '88 suburban w/the 350, here's a few things I did (I had the same priorities as you)...these were simple, outside-the-block things, really if you want reliability as priority #1 - leave the block alone :)

4 core radiator
Electric fan (block off water pump, one less thing to leak/go wrong...or if you want, leave the pump there, but just don't hook it up, then you'll have it as a backup when your electric fans short out :) )
Remote oil filter, just makes it easier to get to and help cool it a little too

Really other than really beefing up cooling, I don't think there's any way to upgrade the reliability, other than just replacing all the parts (tbi, etc). If it were me, and I've been thinking of getting back into an old suburban...I would buy a new crate motor for a 1991 3/4 ton suburban...I believe the motor has 50k mile warranty (100k if installed by a dealer in the original vehicle), and can be warranteed at any chevy dealer...I'm not sure about your budget, but they run $1800-2400...you might need a donor vehicle for all the other stuff (intake, tbi, etc)...but if you want 350tbi, that's what I would recommend. hope that helps :)

ntsqd
06-07-2010, 07:49 PM
The stock TBI heads are poor. Their intake ports are a screwy first attempt at intake turbulence and the combustion chambers aren't all that great either. Late model GM iron heads have induction hardened valve seats. That means that you can't simply grind the valves as the grinding will go through the induction hardening and the valve job will not last. Seat inserts would be the only way to continue to use the heads, however the parts & labor to do the job puts you at nearly the same cash out of pocket as the Vortec heads. I would suggest a set of the Vortec heads be used since you'll gain both power and efficiency from them.

So run the heads that the engine comes with if they are good, but don't spend any money on them.

As far as hydraulic roller lifter blocks go, I'm not aware of any TBI V8's having that. It is my understanding, and I could easily be wrong, that not even all of the TPI engines got hyd. roller cams. I would want the hyd. roller cam & lifters far ahead of wanting a 4 bolt mains block.

I've run electric fans. They work OK on street cars. I'll keep my off highway vehicles with what ever they came with. For the most part those are clutch fans.

1leg
06-09-2010, 12:14 AM
Hereís the skinny on the 87-95 GM truck TBI-

All truck TBI motors from 1987-1995 came with the maligned TBI truck head. High swirl intake and combustion chamber, good for high torque low HP low RPM applications (4x4 and towing). Great for low compression and good for gas mileage, very bad for High HP applications. You can easily make 250+ hp 350+ft torque with a modified 350 TBI truck motor. If you want more then that you will need better heads.
All 87-95 blocks will accept vortec roller cams and lifters. There are 2 motors the less then 8600GVW 200hp, 300ft 9.2/1 compression 64cc heads 2 bolt mains. And the greater than 8600GVW 195hp, 300ft 8.5/1 compression 76cc heads, 4 bolt main HD rods(this is what I bought).
The camshafts in both motors are the same and it is very bad, under .420 lift on both intake and exhaust.

If you need to pass smog with an EGR valve then an 87-95 TBI truck motor built like the one Iím building is the ticket. See my build thread.
If you donít need EGR then a 1996-2001 vortec 350 is the way to go. You can use an Edlebrock performer vortec manifold with a TBI adapter. In order to do a TBI on a vortec with EGR it takes a very expensive GM intake, vortec exhaust manifolds and an EGR adapter tube.
Stock vortec will make 250+hp and 340+ft. easy to upgrade to 300hp/380ft.
Personally I think the Truck TBI with overdrive gets better MPG then the vortec. I have owned both in stock trucks (1993 and 2000). No doubt the vortec make more power but itís at cost to MPG.

The next question is what computer you will run. The 87-92 computers will be easier to set-up if you plan to run a non-GM trans. 93-95 computers are more tunable but more complicated to adapt unless you know what youíre doing(I donít). When you have a new chip burned for your computer you can have the EGR disabled if you donít need it.
The next option is a complete after market set-up. Iím told that the holley pro-jection is junk and not better then the stock TBI, other then it may be easier to set-up and run. Donít plan on smoging a aftermarket set-up.

FWIW: the GM replacement TBI motors are built to 1993-95 specs. They come with a smaller oil pan to clear the front IFS axle housing, and the valve covers are different. But everything else is the same. Iím not changing anything, didnít want to buy a new oil-pump and screen.

If youíre going to buy a donor truck:
if you buy a high mileage truck it might not have the original motor, itís possible that someone could have put a Ĺ ton motor into 1 ton. Not that big of a deal unless you plan to tow a lot.
87-95 HD ĺ and 1 tons had 4bolt main block and HD rods, lower compression.
87-91 4 door trucks, suburbanís and blazers came with pass-side drop transfer case
88-91 2 door trucks and all 92 an up trucks had IFS and drivers side drop transfer case.
87-90 HD ĺ and 1 tons cam with TH400 autos
91-95 HD ĺ and 1 tons cam with 4L80 overdrive autos, need computer to control
87-88 700R4s a junk, 89-92 are way better non-computer control
93-95 Ĺ and LD ĺ tons have 4L60 overdrives, need computer to control.

Good luck.

wrench-head
06-11-2010, 02:18 AM
The best block to start with would be a '638 block from a late TBI truck. The 638 block will have roller provisions and can be 2 or 4 bolt mains. The 638 block is better than the 880 block for only one reason I know of now, the piston bores have deeper skirts that when used in a stroker application keep the piston from rocking at the bottom of the stroke. Any 94 to 95 truck should have this block. It will have all the provisions for roller you just need to buy the lifter and spider kit and of course a cam. The factory LT4 cam is a good mild cam for TBI. With 116 LSA it idles very smooth. The vortec heads are easy just be sure to change the valvesprings to work with whatever cam you choose. They can't handle much over stock. The intake you will need is a GMPP intake and it is a copy of a factory intake used on L31 export vans that had vortec heads and the TBI induction. THe intake is pricey new but is easily found used, I even got mine in a junkyard. Anything else let me know.

LaOutbackTrail
06-11-2010, 02:31 AM
Great info guys. I think the info has given me a start in the right direction.

bftank
06-12-2010, 04:35 AM
i might get chewed out for this but you might consider the 5.0 305 camaro motor for good mpg. for good torque summits 383ht build is nice.

hidesertwheelin
06-12-2010, 05:13 AM
i might get chewed out for this but you might consider the 5.0 305 camaro motor for good mpg. for good torque summits 383ht build is nice.

There is absolutely no noticeable difference in fuel mileage between a 305 and a 350.

tros
06-12-2010, 10:12 PM
The stock flex plate is not all that strong bye an after market one i have broken 2 they brake around the crank bolts.