Some One Help me calculate my compression ratio?is it around 11:5:1?

 

What cams are you using? Engine completely warm?

 

Toda Spec C!

 

engine warm cold or driven for awhile will all change the numbers
very important to use the same methode every time

 

so the engine cold or driving for a whilhe will be higher

 

the hotter it is the higher the numbers will be

 

well in my motor it pegs 300 psi jun 3s with JE 12.5s
i need to figure out how to get a gauge that reads higher

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 555R &raquo;</TD></TR><TR><TD CLASS="quote">well in my motor it pegs 300 psi jun 3s with JE 12.5s
i need to figure out how to get a gauge that reads higher</TD></TR></TABLE>

Go to McMaster.com and order an Ashcroft gauge that reads 400 psi.

 

Can I go off topic just a tad here? How many of you guys actually check your comp. warm? I've allways been scared to do it becaue I am afraid of stripping out the sparkplug holes. You are supposed to take em out of a cold engine.

 

how many miles have you guys driven your cars before you did a compression test? i should have around 12:1, and had crower stage 2's while doing a compression test, at around 300-400 miles on my motor...the guage read 250 across...just wondering if it'll be higher now since i've driven for about 200-300 more miles.

 

okie i'm having the same thing.. What i'm looking for is a 11:5:1 somewhere around there..and i get a reading of .. 235-250 is that a gooD sign or no.. and this is on a Ls Block/ Gsr head, srp 10:1, deck & head has been resurfaced.. ?? is this right or wrong.. adn i'm using the crower stage2 cams..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LsRxtreme &raquo;</TD></TR><TR><TD CLASS="quote">okie i'm having the same thing.. What i'm looking for is a 11:5:1 somewhere around there..and i get a reading of .. 235-250 is that a gooD sign or no.. and this is on a Ls Block/ Gsr head, srp 10:1, deck & head has been resurfaced.. ?? is this right or wrong.. adn i'm using the crower stage2 cams.. </TD></TR></TABLE>
what the hell r u talking about if your pistons are 10:1 how do u come up w/ 11:5

 

230ish is normal for the 10.1 compression motors
as for me
well it always pegs 300 psi after 2-3 pumps so i know its a 12.5 slightly higher since the head was shaved 10 thou
the number isnt important its that they are even across the board
if they are within i think 5 % YOU ARE FINE
ITS WHEN YOU TEST AND YOU GET 3 AT 240 AND 1 AND 200
THEN THERE IS A PROBLEM BEGINNING TO SHOW