TPI or LS1???
#1
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Car: 1989 RS, currently bone stock
Engine: 305 TBI
Transmission: Th700R4
Axle/Gears: None at the moment, bad accident
TPI or LS1???
Hey guys, working on a new third gen project, and I'm looking for a motor. The car was a factory 305 (now carbed, was TBI), but I need something that can make power and get halfway acceptable gas mileage in front of a T56 and 3.42 gears. I only want ~280rwhp, enough to pass someone but not so much that I can't afford to daily it while I'm in school. I know that I can find a 350TPI donor for cheap that is easy and cheap to rebuild and can make that much power with tolerable mileage and good reliability, is there any huge benefit to the LS1 that would justify the headache/expense for a daily driver that's not going to be super powerful? Im only planning to have the motor for a few years then it'll become an all out track car when I buy a new daily, which is why I'm interested in the LS for modifying down the line. The LQx motors look good too, but seem to be even more complicated and expensive than the LSx. Any advice would be greatly appreciated.
#2
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Car: 1989 RS, currently bone stock
Engine: 305 TBI
Transmission: Th700R4
Axle/Gears: None at the moment, bad accident
Re: TPI or LS1???
Also, I am familiar with the LT1, but for the time and money, I see no reason to go with that, I'd rather just put the LS in there.
#3
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Car: 1989 Pontiac Formula 350
Engine: L98
Transmission: 700R4
Axle/Gears: BorgWarner 3.27 Posi
Re: TPI or LS1???
If you're going to modify it down the line, LS is really the way to go. Stock motors put out good power, and will handle the addons you want to do later.
You'll have to work to obtain the rwhp you want on a TPI setup. Good heads, cam, some intake modifications or aftermarket, whatnot. I'm staying TPI just because I want to be "era correct", and working with cali smog restrictions, but in your instance, LS sounds like it ticks the right boxes.
You'll have to work to obtain the rwhp you want on a TPI setup. Good heads, cam, some intake modifications or aftermarket, whatnot. I'm staying TPI just because I want to be "era correct", and working with cali smog restrictions, but in your instance, LS sounds like it ticks the right boxes.
#4
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Re: TPI or LS1???
Why so specific on 280whp?
You have two choices ahead of you.
Either go full bolt-on L98, which is enough to put you mid 13's solidly. Since you don't have an engine currently forget the concept of a TPI car. Its not worth any money.
Go LS route with a cheaper 5.3L swap. The 5.3L will put you in the low 13's, nail great fuel economy, and pass any emissions you want. It will drive like stock and pull like a freight train in comparison with the engine the car came with.
You'll need to source the oil pan, accessories, PCM and harness, but you can find all of those easily enough.
You have two choices ahead of you.
Either go full bolt-on L98, which is enough to put you mid 13's solidly. Since you don't have an engine currently forget the concept of a TPI car. Its not worth any money.
Go LS route with a cheaper 5.3L swap. The 5.3L will put you in the low 13's, nail great fuel economy, and pass any emissions you want. It will drive like stock and pull like a freight train in comparison with the engine the car came with.
You'll need to source the oil pan, accessories, PCM and harness, but you can find all of those easily enough.
#5
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Re: TPI or LS1???
i agree with the thoughts on LS... i have done both and unless a specific reason for TPI (ie want originality, etc) the LS will make more power, be more reliable, and more flexible for future power...
#6
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Car: 1989 RS, currently bone stock
Engine: 305 TBI
Transmission: Th700R4
Axle/Gears: None at the moment, bad accident
Re: TPI or LS1???
Thanks guys. I said ~280whp because a buddy of mine has a third gen that makes about that much power, and it feels like a good balance for the street with good fuel economy. Do you know anywhere to look besides my local pick-n-pull? Also, does the 5.3 have significant advantage over the 5.7? I figure if i could maybe find an old 4th gen with the LS1 I could get it cheap and have it rebuilt. Likewise with the LQ4 out of a truck?
#7
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Car: 91 G92 Z28
Engine: 305 TPI
Transmission: T5
Axle/Gears: 342
Re: TPI or LS1???
Thanks guys. I said ~280whp because a buddy of mine has a third gen that makes about that much power, and it feels like a good balance for the street with good fuel economy. Do you know anywhere to look besides my local pick-n-pull? Also, does the 5.3 have significant advantage over the 5.7? I figure if i could maybe find an old 4th gen with the LS1 I could get it cheap and have it rebuilt. Likewise with the LQ4 out of a truck?
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