Engine SwapEverything about swapping an engine into your Third Gen.....be it V6, V8, LTX/LSX, crate engine, etc. Pictures, questions, answers, and work logs.
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guy up at work has a 96 350 vortec out of a wrecked suburban with 68,000 miles, runs good and is complete. hes asking $600 for it, but before i go ahead and get it for my 91 z28 'vert i need a little info. what kind of HP does these engines have? and how hard would it be to put my TPI system on it and whats all involved after i bought the SD intake? not interested in modding or anything until i stiffen up the body some more and get my tranny. is going with this engine worth it?
I am not sure on the power numbers, but it is a good motor to start w/. It uses a roller cam, should have 4 bolt mains, and has vortec heads. You could put a bit of a cam in it and a good exhaust and it would perform decent. It is designed for a truck though, so in its current configuration it will not have a ton of hp, but more torque instead.
I was thinking it was 260hp. How much of that is the stock intake and exhaust as fitted in the truck choking it down I don't know, but the cam is pretty mild. I would upgrade the cam while the engine is out of the car, it will save the hassle of doing it later. Nothing wild, just a decent mild cam will benefit you...
__________________ Ray87Z
-87 Z28 w/ a Vortec headed 350.
R.I.P. - Just totaled by a 16 year old girl in a 94 Mustang, go figure....
-New ride, 94 Z28 - LT1, A4 w/ 3.23s
new mods: Edelbrock headers, gutted cat, magnaflow catback, Moroso CAI
what kind of difference would my tpi system make on it? i do know that i need the scoggin dickey intake. i am buying the engine this w/e, would i benefit from just selling the vortec heads and putting a set of stock aluminum l98 vette heads on it. im not looking to modify it much at the moment since its going in a convertible, so i still need to stiffen up the body and suspension, before i do any serious moding. i found something saying the 96 350 made 255hp at 4500 rpm and 330 tq at 2500 rpm
With the tpi, dont expect a power gain over stock vortec numbers. The tpi is pretty restrictive. It will make a lot of torque though. The vortec's are pretty good heads, but it just depends on what your plans are because they need a decent amount of modification in order to run a lot of lift. At this poiint, I dont think that they will be your weak point by any means though.
The hp and tq numbers you found are correct, but don't count on it being a 4-bolt main motor, as alot of them were not.
But that's not anything to worry about for a street driven car.
Check my sig to see what i'm putting in my T/A, it's an engine that came out of an 1999 Cadillac Escalade.
Good luck with your swap, I can't wait to fire mine up
__________________ "Speed Limit signs are for reference only"
The 5.7-liter Vortec V8 makes 250 hp at 4600 rpm (last year, the 7.4-liter "big block" V8 made only 230), and 335 lb.-ft. of torque at 2800 rpm (last year the big block was rated at 385 lb.-ft.). This means practically the same hauling power as previous versions of the big-block, but without that monster's penalty in fuel economy.
The example we drove was EPA-rated at 14 mpg city, 18 highway; more than acceptable, considering the Chevy's capabilities.
when i swap the motor and my tpi system will i need to upgrade my injectors? and my fuel pump should handle it with no problems for now right? will i need a custom chip?
im assuming from this swap that it was be just like i have an l98 with vortec heads. just needing as much info as possible.....new to this whole swapping things......especially with the fuel injection
Ive got a '98 long block (neverending project) ..
It came with TBI factory wise ...
If ur aiming for 400 hp with is rather easy ..
ill assume ull need 24 to 30 lb injectors.
ull need the base (400$), injectors, upgrated plenum (urself)
and the aftermarket runners.
Originally posted by theCure when i swap the motor and my tpi system will i need to upgrade my injectors? and my fuel pump should handle it with no problems for now right? will i need a custom chip?
The intake manifold you have will not fit the Vortec heads. The SDPC Vortec lower intake manifold would work if you were keeping the "TPI" manifold. Personally, I wouldn't b/c it's a lower rpm intake.
You should do some PROMs (chip) for your combo for sure. This will let you use your current injectors if you do it right.
Quote:
Originally posted by Spectre The 5.7-liter Vortec V8 makes 250 hp at 4600 rpm (last year, the 7.4-liter "big block" V8 made only 230), and 335 lb.-ft. of torque at 2800 rpm (last year the big block was rated at 385 lb.-ft.). This means practically the same hauling power as previous versions of the big-block, but without that monster's penalty in fuel economy.
Yeah. If torque didn't mean anything.
Quote:
Originally posted by Spectre Ive got a '98 long block (neverending project) ..
It came with TBI factory wise ...
No, it came with a port injection system if it's from a '98 truck.
The 96 L-31 350 vortec motor has a good "TPI" fuel injection system on it already. It looks different, but the
tuning is simular. So you'd gain little or nothing by swapping on your TPI.
They are both tuned long runner- low rpm manifolds.
Work with the stock Vortec EFI system manifold and runners.
A larger throttle valve from a LS-1/6 corvette or 454 vortec efi motor may fit.
The stock vortec cam is quite small.
Swap in a EFI friendly cam of moderately longer duration
and higher lift , same as you would with a TPI system. Install headers and a aftermarket high flow exhaust system.
It will respond to about 300-325hp or so.
Then if you want more power, swap on a Ramjet
EFI manifold as used on the 350 Ramjet crate motors.
The runners are much larger/shorter allowing higher rpm
torque and horsepower. easy 400-450hp.