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Compression

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Old

Feb 21, 2003 | 11:04 PM

#1

Thread Starter

Senior Member

iTrader: (2)

Joined: Jan 2002

Posts: 925

Likes: 0

From: Kingsport, TN

Car: '92 RS, '84 Z28

Engine: 383, L69

Transmission: T56, 700R4

Axle/Gears: 3.42, 3.42

Compression

What would the compression be, if i had 67cc heads, on a 350 with pistons that were dished and had valve reliefs?

I know you can be for sure without other measurements, but i just neeed and estimate.

Kevin

Old

Feb 22, 2003 | 12:05 AM

#2

Supreme Member

Joined: Jul 2001

Posts: 1,766

Likes: 2

From: New Palestine, IN (Just East of Indy)

Car: '85 Z28

Engine: 305

Transmission: WC T5, 3.23 posi

We need to know how big the dish and valve reliefs are. That makes a huge difference in compression ratio.

Old

Feb 22, 2003 | 12:13 AM

#3

Supreme Member

Joined: Apr 2001

Posts: 4,969

Likes: 0

From: USA

Car: yy wife, crazy.

Engine: 350, Vortecs, 650DP

Transmission: TH-350

Axle/Gears: 8.5", 3.42

Once you find all the measurements you need, you can go here www.smokemup.com and use their compression calculator.

Go check it out first and you'll see how intricate ACTUALLY MEASURING for compression is.

Old

Feb 22, 2003 | 05:16 AM

#4

Member

Joined: Jul 2002

Posts: 475

Likes: 1

From: San Diego, California

A 350 with flat tops and 64 cc heads is usually in the neighborhood of 9.5 to 10.2-1, it would at least be less than that!

Last edited by 85TPI400; Feb 22, 2003 at 05:23 AM.

Old

Feb 22, 2003 | 02:12 PM

#5

Supreme Member

Joined: Sep 2001

Posts: 6,111

Likes: 53

From: Ontario, Canada

Car: 1988 Firebird S/E

Engine: 406Ci Vortec SBC

Transmission: TH-350/3500stall

Axle/Gears: 7.5" Auburn 4.10 Posi-Traction

between 8.45:1 and 9:1.

just right for a blower...

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