V8 Swap into S15 Jimmy - NJFBOA - Home of New Jersey's Camaros and Firebirds

91chevywt · 08-04-2011, 01:54 PM

So, I'm seriously considering a V8 swap in my '94 Jimmy. I'm at the planning stage at the moment. I want something that appears stock, but I'm hoping to build for about 300 horsepower. I want to use a TPI setup from an F-body, or maybe even a TBI setup from a truck if it's cheap enough. My main goal is a factory look, making it work like it would have from the factory. A cam swap and tune would be minimum modifications, I'm thinking I might have the heads ported and freshened up as well. I want to stay with a hydraulic roller cam setup.

I want to stay 1st generation small block chevy, because I'm hoping to bolt the 4.3 accessories to the front. An LS1 or LT1 wouldn't allow me to do that. Is this a sound plan?

My Jimmy is a 4x4, and I want to keep it 4x4. In 1994, is the transmission the 4l60 (fully mechanical) or the 4l60e (electronically controlled)? I know it went electronic in '94 for the F-body. I'm having a hard time finding any wiring running to the transmission besides the VSS, anything specific I can look for to distinguish between the electronic and mechanical trans? Are the transmission and engine controlled by the same module? I was hoping to keep my transmission and build it up a bit, I suppose that depends on what I have. Could I just get a mechanical 4l60 from a full size 4x4 truck, and bolt it to my NP231? I swapped from the NP233 to NP231 last year and want to keep it. Do the full size truck transmissions have the 5 bolt mounting flange as well?

In the end, I want something that runs like a raped ape. I want to do this as cheap as possible too. Under $1000 total. This is why I want to plan things out to get this setup as cheap as possible. Time is no obstacle. I'll wait around for the best deals possible. I'm not quite ready to start buying up parts, but I want to have a complete parts list and price it all out beforehand, and budget it as reasonably as possible.

Flippindabird · 08-04-2011, 04:59 PM

i know u said no ls.... that being said i just thought i would enlighten you to the fact that A: the 5.3L truck engine is dam near 290chp from the factory B: it was used behind the 4L60e transmission, and C: you should be able to get the COMPLETE assembly; engine, harness, computer, accessories etc for around or UNDER 500$ that leaves 500 ish for exhaust and mounts... im pretty sure alot of others would agree and if you break the 4wd the truck stuff should swap right in

with your v6 torque converter you should be stalling at around 2500 rpm, with a little more cam (cheapo is LS6) you should be pretty dam quick, then add in the fact that youll have more potentioal to make power later on down the line its almost a no brainer... i sure as hell wish i could have swapped a 5.3 into my wifes mountaineer

that dam thing cost me 1000 for a 300hp 5.0L

btw check this site out https://www.s10v8.com/store/home.php?cat=28

Flippindabird · 08-04-2011, 05:04 PM

oh yeah its gonna take alot to get 300 from a tbi motor even tpi will need some $$$ thrown at it... they are 200-240ish hp factory rated

91chevywt · 08-06-2011, 07:08 PM

I'll give the LS swap more thought, but I'm not too sure I want to go that route. The iron block motors I've seen run about $500 minus accessories and I imagine getting the right accessories and oil pan setup for the 4x4 could be an issue along with the transmission. If I could have anything I want, LS would be it no doubt but I'm just not too sure. I'd even consider picking up a wrecked truck to part out and scrap afterward, but we'll see.

I wanted to stay Gen I EFI for the simplicity and straight forward nature of the swap, sometimes complete running setups can be had for less than $400 including harness and computer. I'm considering laying off the modifications for the time being, and just get a complete engine and transmission in the truck, and do modifications later. The biggest restriction on a TBI or TPI setup should be the cylinder heads and camshaft, not too expensive to have the heads ported/surfaced and get a new cam. Getting a custom tune for these ECMs seem to be pretty cheap. I'm starting to think I should pick up a full mechanical 700r4, not too sure what I want to do with regards to that either.

emolineaux · 08-06-2011, 08:04 PM

hey bill stick with your gut feeling on this with the 1st gen sbc. like you stated parts are cheaper and would be easier. yes an ls swap would be very nice but the parts for that swap are a little more expensive. i was looking into doing the v8 swap on my sonoma but sold it before i spent too much money on it lol.

91chevywt · 08-06-2011, 09:30 PM

Yeah this is going to be one of those projects that I really pinch pennies on. I've just been holding on to the Jimmy trying to figure out what to do with it. The truck is in awesome shape, way above average for a Gen 1 S-truck. I've been having the desire to drive something "fast" and a little fun and figure I can get a little power in it for not too much money. I learned a lot from the LT1 swap in my Camaro, and I feel getting a decent setup in this truck should be easier, but we'll see. I'm running out of things to tinker with and wrench on so after a night of looking the Jimmy over I think I'm going to rip it apart eventually.

Eric, did you pick up any literature for the v8 swap? I was thinking of picking up the "Jags that Run" book but I'm not sure I'll learn anything that isn't available on the internet already.

Flippindabird · 08-06-2011, 11:28 PM

heads cam and induction system are all restrictive... tbi especially, and aftermarket higher flowing parts for tpi is expensive... id say if you gotta stay gen I then go carb cheaper, lighter and just as powerful just my .02 i wont be mad regardless good luck with your build whatever you decide

91chevywt · 08-07-2011, 09:44 PM

You've got a point about a carb setup...sometimes I see complete motors selling for much less than what it takes to build one. The biggest problem for me is I know much much more about EFI (specifically early 90's GM stuff) than I do about tuning a carb. But I suppose the best way to learn is to get a carb'd motor

sweetbmxrider · 08-08-2011, 07:38 AM

Does the current throttle body have a kickdown cable? That would tell you if the trans is electrically controlled or not.

91chevywt · 08-08-2011, 12:29 PM

Quote:

Originally Posted by sweetbmxrider

Does the current throttle body have a kickdown cable? That would tell you if the trans is electrically controlled or not.

You're right, I forgot about that. It doesn't have the throttle valve cable, so it's an electronic trans (4l60e). While I was looking over the truck, I checked out the window sticker which is still in the glovebox and noticed it said something like, "electronic 4 speed overdrive transmission" so that would have been a dead giveaway as well had I looked earlier!

emolineaux · 08-08-2011, 05:34 PM

hey bill i never bought any swap books on it. just read alot online. it seemed pretty straight forward for the most part.

Flippindabird · 08-09-2011, 01:28 PM

yeha my cousin converts an s10 like once ever 6 months lol so it cant be too hard, good to do your researcha head of time though

91chevywt · 08-09-2011, 09:59 PM

http://www.youtube.com/watch?v=8MhkKM-4ztE

This is pretty much the end result I want

Flippindabird · 08-10-2011, 10:48 PM

hope you can drive a little better then that LOL

greenformula92 · 08-12-2011, 08:15 AM

just remember a full bolt on TPI still isn't going to make 300...so you will most definatly have to throw some money at a TPI

Flippindabird · 08-17-2011, 11:20 AM

Quote:

Originally Posted by greenformula92

just remember a full bolt on TPI still isn't going to make 300...so you will most definatly have to throw some money at a TPI

^^^this again

zraffz · 08-20-2011, 03:51 PM

TBI motor is a better bet than a 5.3 or TPI in any heavier application.

The TBI year trucks came with swirl port heads which didn't flow worth crap.
My old man had a 87 K10 with 4.10's, bored .030", flat tops, hand ported swirl ports, and a mild cam. In 4wd on 33" all terrains it could brake stand. That truck used to give 3rd gen f-bodies a run for their money lol.

Flippindabird · 08-21-2011, 07:19 AM

Quote:

Originally Posted by zraffz

TBI motor is a better bet than a 5.3 or tpi in a heavier application

^^^ wrong.... tpi makes ALL of its power and torque down low... im not even gonna start with the 5.3, in a blazer no less? which is lighter then what they come in from the factory!? im thinking 15.8 in 90* in my 6300lb 4wd truck is pretty good for a 5.3, and itll give stock 305 TBI auto 2.73 rear geared thirdgens a run for their money