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-   -   Compression on a FD (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/compression-fd-89651/)

95R2-89TII Ground Zero 06-19-02 03:24 PM

Compression on a FD
 
Does anyone know what the compression is supposed to be on an FD? I'm going home to do a compression check, so I need to know ASAP. Thanks in advance.

Todd

95R2-89TII Ground Zero 06-19-02 09:46 PM

Anyone? I asked a qualified mechanic and all he said was that the 7 is measured in KM not PSI

Nathan Kwok 06-19-02 10:03 PM

You can measure it however you want, but the minimum standard for the '93 shop manual is 7.0 kg/cm^2 or 100psi, with a 1.5kg/cm^2 maximum differential between faces. This was revised down to 6.0kg/cm^2 or 85psi with the same differential for the '94 and '95 shop manuals. The factory new spec was 8.5kg/cm^2 or 120psi.

P'cola FD 06-19-02 10:06 PM

No lower than 85 psi with no greater a difference between chambers than 21 psi.
An easy way to do it is to do the test with the little check valve in the tester to see how much the total compression is. Then take the valve out and see how much the needle moves for all three chambers for each rotor. They should bounce pretty evenly.

95R2-89TII Ground Zero 06-20-02 10:20 AM

Thanks guys. I appreciate the info. I'll let you know how it turns out today.

95R2-89TII Ground Zero 06-20-02 02:28 PM

I just took the rest of the day off work and tested my compression. The front rotor came in at about 95-97 PSI. The rear came in at about 95-97 PSI too. So I know that isn't the problem. Thanks for the help.

ttpowerd 06-20-02 02:33 PM

Congrats!

jpandes 06-20-02 02:37 PM

I bet your relived to find out that your apex seals are still intact...congrats!

95R2-89TII Ground Zero 06-20-02 02:38 PM


Originally posted by jpandes
I bet your relived to find out that your apex seals are still intact...congrats!
Yeah, I was really happy when I read the meter and saw the results.

Nathan Kwok 06-20-02 05:12 PM

Congrats :). Those numbers are very good considering they are identical for both rotors, a very good sign.

gz91rx7 06-20-02 06:46 PM

Man that was so releaving! Well now we just have to find away to get my TII to michigan!!!!

tookwik 06-20-02 08:41 PM

9:0:1

cabaynes 06-20-02 10:30 PM

how exactly does one check the compression at home? i thought you had to take it to a specialist... and seeing how i am looking for FDs now, i check boost, but could i also easily check compression as well? how would i go about doing that? thanks for any help...

95R2-89TII Ground Zero 06-21-02 01:15 PM

Its actually pretty simple. I just borrowed a compression meter from a mechanic friend of mine(Steve Dewitt). Then I took the trailing plug out of the block on the front rotor, stuck the meter in the spark plug hole, and had someone(GZ91RX7) crank it over a few times. Then you just read the meter, and then do it to the other rotor. Make sure to disable the ignition system before doing this though. Really easy. Good luck.


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