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compression ratio of stock 350. 55-86

Old 01-29-2001, 08:04 PM
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Car: 96 Formula/82 T/A
Engine: LT1/350 TPI
Transmission: T56/TH350
compression ratio of stock 350. 55-86

ok. i bought a 350 rebuilt crate motor from kragens auto parts. i think the compression is 8.5:1 , but i want to get new heads and i want to go to 9.3-5:1 at least. but i dont want to go over 10:1. what cc chambers should i get with my heads. im thinking of getting S/R torqer. they have 67cc and 76cc.
thanks.

oh. and i want to get edelbrock proformer plus cam (part number EDE-2102). right now i have 1.6 proform rollor rockers. but edelbrock says to keep stock ratio (witch is 1.5) will it still work with 1.6. thanks


the reason im doing all this is because i crushed a lifter. so i might as well when the intake is off.

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RED82TA5.7L

1982 Pontiac Trans Am
Cross-Fire Injected 5.7l V8
New TH350 Raptor with a shift-kit, 2600 stall torque converter, Eldebrock TES Headers, 3" Hooker Cat-Back.
Mods: 1.6 Proform Roller Rockers, electric fan, Corvette 5.7L computer chip, K&Ns.
Audio: JVC Kameleon CD deck, Jenson 4x6 front, Eclipes 6x9 rear, 2 10" mTx T4000 powered by a mTx 200watt amp.
Black Powder Coated 1990 16x8 Formula Wheels with 245/50/ZR16 Perelli P7000.
For Pictures go to
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Old 01-30-2001, 10:35 AM
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Car: 96 Formula/82 T/A
Engine: LT1/350 TPI
Transmission: T56/TH350
ttt, PLEASE HELP

------------------
RED82TA5.7L

1982 Pontiac Trans Am
Cross-Fire Injected 5.7l V8
New TH350 Raptor with a shift-kit, 2600 stall torque converter, Eldebrock TES Headers, 3" Hooker Cat-Back.
Mods: 1.6 Proform Roller Rockers, electric fan, Corvette 5.7L computer chip, K&Ns.
Audio: JVC Kameleon CD deck, Jenson 4x6 front, Eclipes 6x9 rear, 2 10" mTx T4000 powered by a mTx 200watt amp.
Black Powder Coated 1990 16x8 Formula Wheels with 245/50/ZR16 Perelli P7000.
For Pictures go to
http://members.theglobe.com/RED82TA57L/mycar/


A cool Trans Am site with Message Boards http://www.transamgta.com
Old 01-30-2001, 11:37 AM
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Red,

You will not get a big response since the question you ask requires clarvoiancy on our part. But....I'll try to help.

Assuming you have a .030 overbore on your block, you have a swept cylinder volume of 727.41 cc's.

Presuming your block was not decked any or very little, you have a deck height of .020.
This is about 4.4 cc's.

Presuming you will use a .041 compressed thickness head gasket, this will be 9.1 cc's.

Presuming you have a cheapo cast piston, it's probably got an 11cc dish and a ring land volume of 1.5 cc's.

Using a total volume of 753.41 cc's plus a 58cc head, we get 753.41 plus 58 divided by
58 + 4.4 + 9.1 + 11 + 1.5

Equals 811.41 divided by 84 = 9.66 to 1

Perfecto Rocky, but you'd best find out for sure if those pistons are really the 11cc dish type. A flatop will make much higher compression. Also, that .020 deck height is a guess. It could be anywhere from .040 to zero.

There are far too many presumptions in here for me to say "go for it" right now.

The S/R torquers are "stock replacements". You may want to shop for a set of Corvette 58cc heads instead, since those S/R's need to be fully ported and polished before you see a big power increase.

Good luck.
BOR

[This message has been edited by Box of Rocks (edited January 30, 2001).]
Old 01-30-2001, 12:54 PM
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Join Date: Sep 2000
Location: Morgan Hill, California. Age: 20
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Car: 96 Formula/82 T/A
Engine: LT1/350 TPI
Transmission: T56/TH350
thanks

------------------
RED82TA5.7L

1982 Pontiac Trans Am
Cross-Fire Injected 5.7l V8
New TH350 Raptor with a shift-kit, 2600 stall torque converter, Eldebrock TES Headers, 3" Hooker Cat-Back.
Mods: 1.6 Proform Roller Rockers, electric fan, Corvette 5.7L computer chip, K&Ns.
Audio: JVC Kameleon CD deck, Jenson 4x6 front, Eclipes 6x9 rear, 2 10" mTx T4000 powered by a mTx 200watt amp.
Black Powder Coated 1990 16x8 Formula Wheels with 245/50/ZR16 Perelli P7000.
For Pictures go to
http://members.theglobe.com/RED82TA57L/mycar/


A cool Trans Am site with Message Boards http://www.transamgta.com
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