20 Valve Compression readings.

**S.W.A.M.I.** · 20-11-2006, 02:50 AM

150psi on a 20v of any kind is low
its time for an overhaul

**dave_g** · 20-11-2006, 07:21 PM

Does anyone have a manual for the silvertop?

I'd like to know what the normal cranking pressure should be becasuse I bought a silvertop 20 valve from toyospares the other day to replace 16 valve in my ae82. The compression test showed about 168psi across all 4 cylinders. I have a feeling that this is a bit low. Does anyone know what the cranking pressure should be for a silvertop? Trekka273 says the blacktop should read about 193psi and I guess the silvertop should be similar but I'd like to know what a factory manual says.
Thanks Dave.

**Trekka273** · 20-11-2006, 08:44 PM

I have never seen nor heard of a silvertop manual been in existence.

When I previously had a silvertop I looked high and low for a manual and couldn't find one, and I contacted Japan, South Africa, etc. All advised that they did not know of one. I used the blacktop manual instead... I cannot imagine that there would be too much difference in the compression readings of each engine.

**Jorrs** · 20-11-2006, 09:39 PM

wouldnt the AE101 Levins use a manual for the 20valve as they had the engine ?

**dave_g** · 20-11-2006, 09:42 PM

Hmm.. if that's the case and the pressure should be nearer to 190 psi, then maybe I shouldn't have bought this 20 valve. Crap.

**BigWorm** · 20-11-2006, 10:35 PM

Bah, I wouldn't be too worried about the compression results of each cylinder, unless it's a quality comp guage done by someone well versed in comp tests. As long as they are even between each cylinder & the motor runs ok you should be fine.

**Jorrs** · 20-11-2006, 11:36 PM

well, it was tested again today, and last time the throttle was closed, this time it was 168 across all four. so much better result.

**cambelt** · 21-11-2006, 12:05 AM

Dont you people listen , import motors sit around for a long time its very normal to have comp readings that vary or are low , dont right a motor off just because of a few low comps.
Dave