Need more top end power
#1
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Car: 1989 Trans Am GTA
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 3.73
Need more top end power
I have 350 Tpi. I wanted some recommendations on some mods to help with top end power.
#3
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Car: 89 Firebird
Engine: 355 TBI
Transmission: 700R4
Axle/Gears: 10 Bolt.Posi-3.73s
Re: Need more top end power
Thing is the TPI system was designed for all its power to be made in the lower RPM range.
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Car: 1989 Trans Am GTA
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: 3.73
#6
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Throttle body won't change anything. Porting the lower manifold will give better airflow but won't change rpm. Aftermarket runners will open up rpm but need porting make a real gain. The plenum needs to be ported to match the runners too. Factory runners are too thin to port. All that costs more money than a hsr and will give you less gains. That's why I suggested it. Don't get me wrong I'm replacing my factory parts with ported soon. The hsr is just a more effective design.
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Car: 92 Z28
Engine: LS3
Transmission: TR6060
Axle/Gears: Strange S60 3.73
Re: Need more top end power
The length of a TPI runner along with manifold and head intake length determine what RPM the tuned wave effect will occur. If you shorten this length from stock unit, your power band will move up some. SLP's like Orr mentioned would do this since their runner length is shortened over stock runners. That alone would help out some. Mild porting on base would further help but maybe not to that great of an extent if you are not upgrading other items (cam, heads, etc).
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Car: 1990 G92 IROC Z Miniram
Engine: 388cu 6.4 Liters
Transmission: G-Force T5
Axle/Gears: 3.73 Gears
Re: Need more top end power
Just put a full exhaust system. The best mod ever. And the biggest gains without a chip tune.
#9
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Re: Need more top end power
Originally Posted by Red_1989_GTA
But would porting it help give more top end?
Originally Posted by Red_1989_GTA
And what about getting a bigger throttle body? would that help also?
#10
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