Guys
 
I have searched high and low and have found so many speculative answers for a Red top.
 
I have 178 psi on all four cylinders warm, TB wide open, injectors still firing new red top swop.
 
Any advice appreciated

Hmm, can give you the gen3 specs. With regards to comp tests, in general your just checking for a large difference between the cyl's as comp testers themselves can be inaccurate.

Id have thought a redtop would be over 200psi tho.

Compression value to compression ratio is not exactly linear, think it also depends on volume so it may not be that much higher than a 3sge

Yeh, I jst have a vague memory of na 3sges being over 200psi, but ill check my bgbs when I get home. Vaguely remember gtes being 160-180ish.

But my memory likes to play tricks on me.

If you ask on the beams forum, mandalay(or one of the others with the beams bgb cd) should be able to post pics from the bgb relevant pages.

According to a spec sheet I saw, the Gen 2 3sge comp ratio is 10:1, Gen3 3sge is 10.3:1, and 3sge BEAMS is 11:1.
 
But I've noticed that even though the gen3 has a higher comp ratio, the service manuals for the 3sge Gen2 and Gen3 motors both show the same the comp test figure (178 PSI or more) which coincidentally is the same as what you got.
 
I don't have a BEAMS manual, but as ace says test gauges can vary.
The main thing is to have only small variations between cylinders, but if you're worried about maybe it try another gauge.
 
 
 

Thanks Guys LEt me PM MAndalay for a response

Bgb says 192psi or more for gen3

Thanks, well I may be in trouble then, strange engine looked so clean and looks like genuine low km. Even had original T belt. Never know how long it sat in warehouse waiting for a buyer (had cut harness and no ECU), rings maybe sticking to pistons. The pressure of all 4 is very similiar.

Some loss in comp is excpected. If it doesnt use excessive oil or blow smoke I wouldnt be too concerened.

If you want to confirm condition of engine you need to do a leak down test.