Can you guys tell me what the compression ratio would be with 280 psi across the board????
GSR Block
GSR Head
Toda B's
Unknown Pistons???

 

Compression test results are entirely too dependent upon other factors to give anything close to a precise compression ratio estimate.

 

Just want an rough est. I'm guessing somewhere around 12.0:1??????

My guess is CTR pistons?????

 

CTR pistons would give you a good bit more than 12.0:1, but 280 is a reasonable number for CTR pistons.

 

alright that's what I was thinking Thanks for the info

 

Just a small town girl, livin' in a lonely world
She took the midnight train goin' anywhere
Just a city boy, born and raised in south Detroit
He took the midnight train goin' anywhere

A singer in a smokey room
A smell of wine and cheap perfume
For a smile they can share the night
It goes on and on and on and on

Strangers waiting, up and down the boulevard
Their shadows searching in the night
Streetlight people, living just to find emotion
Hiding, somewhere in the night

Working hard to get my fill,
everybody wants a thrill
Payin' anything to roll the dice,
just one more time
Some will win, some will lose
Some were born to sing the blues
Oh, the movie never ends
It goes on and on and on and on

(chorus)

Don't stop believin'
Hold on to the feelin'
Streetlight people

 

I'm about 12.3:1 with an even 275psi across the board

 

LOL Journey

 

First album I ever wore out!!!!!!

Second was Foriegner 4.

40 is just 15 mounts away

 

my b20vtec with 12.7:1 CR has read 245psi I think 280 must be around 13.5:1 cr.

 

What everyone has to remember is that often, no two compression gages read exactly the same. Also, unless everyone does the compression test the same way (injectors shut off and throttle held wide open while cranking) the test numbers can vary quite a bit. PSI ratings you get from doing a comp test should only be used as a guide to see how the engine cylinders compare. Those psi numbers DO NOT correlate to any fixed compression ratio (ie 280psi=13:1). The only way to properly measure your compression ratio is to know all the dimensions/parts that affect the cylinder volume and calculate it out from there.

 

That is very true but I just kindy wanna an est. ^^^^

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Robs_B18c &raquo;</TD></TR><TR><TD CLASS="quote">That is very true but I just kindy wanna an est. ^^^^</TD></TR></TABLE>

I think it's about time for a new headgasket, don't you?

 

It's my bro's motor we should just do a headgasket and find out what kind of pistons are in there and what's the bore is... all that and a new headgasket.... well I just decided right now we'll do a headgasket this weekend

 

u find out what hes got? casue i have 245/250 on my ITR, and all i have is stiock internals and a spoon headgasket, in theory i have 11.1 stock + the .4 Teh headgasket gives me..... equals 11.5!

 

Is this a street motor w/ what octane? you may want to put a fatter gasket in there ya dig.

 

when i had ctrs in my gsr motor, my cr was about 13.2 and my compression was 245 across all cylinders

 

well i think your compression is 19.1 because i sold you that motor little man. im j/p get that **** tuned before it really detenates.

 

i'ma at just around 11.5 compression with 225 psi...
i've also heard of other gauges reading higher than others for some reason....
also engine temprature making a difference too...

 

yeah make sure the engine is at normal operating temp, the rings are operationg right when their cold....

 

I think you guys should try reading my post above since I already covered the issue about different readings and why...

 

thanks for the info, i dont know y, but i didnt even see/read ur post!! thanks!

 

You cannot accurately tell the compression ratio by doing a compression test. Like someone said above,Too many variables. If you dont believe it, advance your exhaust or retard your intake camshaft. Changing the valve overlap will produce different #'s...