350 tbi vs tpi short block?
#1
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Car: 88 GTA
Engine: L98
Transmission: 700r4
Axle/Gears: 3.27 9bolt
350 tbi vs tpi short block?
I blew my tpi and found a rebuilt 350 tbi motor.
I was wondering what is differnt on the tbi short block from the tpi?
Thanks
I was wondering what is differnt on the tbi short block from the tpi?
Thanks
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Re: 350 tbi vs tpi short block?
the TBI engines didn't get roller lifters, but you can swap all that stuff over. Otherwise, they're functionally identical. Have at it.
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Car: 88 GTA
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Re: 350 tbi vs tpi short block?
what about the pistons? Are the l98 ones better? compression the same?
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Car: 1991 Camaro Z28
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Re: 350 tbi vs tpi short block?
Are you 100% on that? Not doubting you, just making sure. My GF's 91 RS has a roller short block. We always assumed it was the stock 305 motor, but now I may need to go check what it really is.
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Re: 350 tbi vs tpi short block?
All the '87-up passenger car 305s were roller. All the '88-'95 truck TBI V8s were non-roller. All the '88-up 4.3s were roller. All '87-up blocks will accept stock rollers.
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Car: 88 GTA
Engine: L98
Transmission: 700r4
Axle/Gears: 3.27 9bolt
Re: 350 tbi vs tpi short block?
So would it have the same compression as my l98 if I use my l98 heads?
I just dont wanna lose power at all
I just dont wanna lose power at all
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Car: 91 Trans am
Engine: built 360 TBI
Transmission: built 700r4
Axle/Gears: 10bolt/3.23
Re: 350 tbi vs tpi short block?
http://www.kb-silvolite.com/calc.php?action=comp
91-92 firebird service manual says 9.75:1 CR for the L98.
TGO tech shows 9.3:1 CR for the 88 L98 https://www.thirdgen.org/1988-pontiac-firebird
Last edited by thomas1976; 06-13-2010 at 07:04 AM.
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Re: 350 tbi vs tpi short block?
9.75:1 was a typo.
And if the TBI short block you're looking at does have dished pistons, then you don't HAVE to do all what Thomas typed, it'll be close enough to safely use on pump premium. When winter arrives, then you can safely experiment with lower octane.
And if the TBI short block you're looking at does have dished pistons, then you don't HAVE to do all what Thomas typed, it'll be close enough to safely use on pump premium. When winter arrives, then you can safely experiment with lower octane.
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Re: 350 tbi vs tpi short block?
that's the thing, NO '91-'92 V8 F-cars actually came with flat-tops. 9.25:1 is close enough to precise, a quarter ratio either way has no real impact on choosing a cam for one of these engines. You're still looking at pump premium for over 90% of the possible situations.
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