TPI off 85 Vette
Thread Starter
Intermediate
Joined: Apr 2007
Posts: 40
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From: Garland Texas
TPI off 85 Vette
Will a TPI fit under the hood of a 1977 Vette?
How much HP can I get from a TPI on a 400 cid small block?
I found a almost complete TPI setup for a good price and I was thinking it would be cool on a 77.
How much HP can I get from a TPI on a 400 cid small block?
I found a almost complete TPI setup for a good price and I was thinking it would be cool on a 77.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I was told TPI will fit under a '77 hood but it's close and they may have been wrong. I'll leave that to someone who may know for SURE.
On a 400 small block TPI will be a bad choice. TPI was originally designed for the 305, and later adapted to the 350. Even on the 350 it seemed to get winded at high RPMs. On a 400, which I almost did, the effects would be even worse.
A better option that TPI would actually be TBI, LT1, or one of the after market version like Stealth or Mini Ram.
TBI has a lot more tunability built into it and you get the benefit of a simple install with a throttle body as opposed to fuel rails and injectors.
On a 400 small block TPI will be a bad choice. TPI was originally designed for the 305, and later adapted to the 350. Even on the 350 it seemed to get winded at high RPMs. On a 400, which I almost did, the effects would be even worse.
A better option that TPI would actually be TBI, LT1, or one of the after market version like Stealth or Mini Ram.
TBI has a lot more tunability built into it and you get the benefit of a simple install with a throttle body as opposed to fuel rails and injectors.
Last edited by Durango_Boy; Jun 15, 2007 at 11:01 PM.
Burning Brakes
Joined: Nov 2005
Posts: 1,143
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From: Leander Texas
The TPI will fit under the stock hood.
Make sure you get the whole wire harness with the TPI system you are going to aquire.
I can't answer the HP question as to what you should expect, but I had a noticable neck snapping increase in low end torque when I did the swap. I've never dynoed the car to find out what the differance was.
Make sure you get the whole wire harness with the TPI system you are going to aquire.
I can't answer the HP question as to what you should expect, but I had a noticable neck snapping increase in low end torque when I did the swap. I've never dynoed the car to find out what the differance was.
Last edited by DR.Jay; Jun 15, 2007 at 10:58 PM. Reason: typing while drinking= bad spelling
Race Director
Joined: Mar 2001
Posts: 11,322
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From: Living in the Hartland
Test done on a 383 produced 410 hp and 501tq so you should about the same hp but more torq. You can siamese the base to gain some additional hp but unless you are going to tow a small town then a stock tpi would not be a choice for a performance 400.
http://www.compcams.com/Community/Ar...?ID=1737510521
http://www.compcams.com/Community/Ar...?ID=1737510521
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From: Cape Cod, Mass.
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TPI is great for low end torque but will not rev much over 4500 RPM's. 383's have plenty of low end grunt. I would not go with TPI on a stroker unless I was looking to do some stump pulling.
Team Owner
Joined: Jul 1999
Posts: 65,492
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From: Orange Park Florida
I look at it from economy and torque, and ratios....if he has say a 336 or milder rear ratio, and an overdrive tranny, that TPI on a 400 won't even have to downshift at 60 to pull really hard, everyone with a SBC thinks of 6000 rpm redlines, if not more....unless he is into dragracing, I think the olde tyme school of Pontiac engineering, 550 ft lbs at 2000 rpm is a good thing, really move some freight...but the usual questions on the intended purpose of the car....
all the above comments by other guys do apply.....
all the above comments by other guys do apply.....
Team Owner
Joined: Oct 2004
Posts: 23,831
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From: Springfield MO
St. Jude Donor '07
The LT1 manifold can be modified to work on early heads, and it doesn't have the breathing problems of the TPI. A 400 has enough natural torque to completely overcome any loss from not having the TPI's long runners.
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Thread Starter
Intermediate
Joined: Apr 2007
Posts: 40
Likes: 0
From: Garland Texas
Tpi
I would rather have lots of torque the lots of HP.
Thanks for the info.
500 ft pound of torque and 410 HP would be awesome!!!
Stock gears, AC and Auto trans,, 500 fpt at 4000 rpm
That is one hell of a street motor
Thanks for the info.
500 ft pound of torque and 410 HP would be awesome!!!
Stock gears, AC and Auto trans,, 500 fpt at 4000 rpm
That is one hell of a street motor
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
hehehe.....With THAT kinda torque, you got a killer street engine....you won'd win any drag races with super speeds....but with street tires you won't need 1st gear either....
with that TPI and a stock L48 '72 vette engine, I started out in second gear with my wide ratio muncie all the time 336 rear....no point to shifting any more tha necessary in traffic.....2-4, next light, 2-4, hell with it....
once in a while on a steep hill....1-3 then 4.....God, I"m lazy...
