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-   -   compression ratio (https://www.racingjunk.com/forums/showthread.php?t=23917)

Tod74 04-19-2009 09:48 PM


Originally Posted by Jordan1984
Yes I have done many compression checks .

Ok....

what is the compression ratio of an 8 cylinder engine that gets cranking compression readings of

234,237,232,234,233,235,231,236?

suicidebomb 04-19-2009 10:29 PM

Tod, I came up with 234, or about 16.5:1. How bout it? Am I within a tenth?

Tod74 04-19-2009 10:30 PM

....

suicidebomb 04-19-2009 10:33 PM

..........Tod ain't aswering, so I must be spot on..........Tod, give me a call, my number is BR549.

I972Nova 04-20-2009 02:49 AM

Im done trying to beat the dead horse. You my friend do not have a clue about getting a compression ratio and you should find a new mechanic if he is telling you that there is a guage that gives you compression and not just cranking pressure.


Get any manual and look it up, or ask any full time mechanic, not a weekend backyard mechanic.
I guess real world wrench turning experience and ASE certifications take a back seat to the brilliance you can attain by reading a Haynes manual :roll:

TopspeedLowet 04-20-2009 03:10 AM


Originally Posted by DragsterJosh
Im done trying to beat the dead horse. You my friend do not have a clue about getting a compression ratio and you should find a new mechanic if he is telling you that there is a guage that gives you compression and not just cranking pressure.


Get any manual and look it up, or ask any full time mechanic, not a weekend backyard mechanic.
I guess real world wrench turning experience and ASE certifications take a back seat to the brilliance you can attain by reading a Haynes manual :roll:

Thanks for saying this DragsterJosh, I think a little miss reading or real general source material "grossly misunderstood by the reader" must have caused this nonsense. I would have thought that when every one was :lol:, at this nonsense, the author may have re-thought his answer prior to insulting other race junkers that are politely giving him a reality check . Cranking compression has no relation to static compression ratio, DUH... Cam timing will have the greatest role in manipulating the cranking numbers up and down. Advanced cam timing settings will give higher readings and retarded settings will give lower PSI numbers, no matter what the calculated COMPRESSION RATIO is, changing only the cam timing without any physical volume or ie, compression ratio changes.
PS, We don't have to be a full time mechanic's to understand printed material in a repair manual, but it appears someone obviously does.
Bruce
Retired master ASE tech

radicalz 04-20-2009 10:06 PM


Originally Posted by Tod74

Originally Posted by Jordan1984
Yes I have done many compression checks .

Ok....

what is the compression ratio of an 8 cylinder engine that gets cranking compression readings of

234,237,232,234,233,235,231,236?

Using his formula...I get the same answer as Tod...hey where...what the..

THERATTLER 04-21-2009 08:38 PM

not making fun or anything but you don't have a clue as to what you are talking about , if you think I don't know anything about motors , check out the picture by my name , I have built every motor ever been in this dragster , there is no compression guage that reads COMPRESSION RATIO , it reads pressure in pounds..SORRY :(

Jordan1984 04-21-2009 08:52 PM

SORRY FOR GETTING MY INFORMATION MIXED UP AND GOING BY WHAT 1 INDIVIDUAL HAS TOLD ME- HE HAS BEEN RIGHT EVERY OTHER TIME THAT I HAVE WENT TO HIM FOR INFORMATION. I DID GET IT CONFUSED. MY BAD. IM NEW TO RACING, GETTING MY FEET WET AND LEARNING AS I GO, LEARNING FROM MY MISTAKES AND I HAVE MADE ALOT OF MAJOR MISTAKES ON MY WAY BUT I HAVE LEARNED FROM THEM. I WILL NO LONGER GO TO THE MECHANIC WHERE I WAS GETTING MY INFO FROM, I WILL TURN TO HERE FOR MORE INFORMATION. What mistakes have I made? I ruined a 200 4r trans, broke lifters and pushrods, wiped out the lobes on 2 cams. Even as far as getting my arm stuck in driver side header, droping the 7/16 to the floor, and waiting cramped up for my dad to find me 4 hours later. It might be a street car, but my ad number is 1526368 if anyone wants to check it out.

THERATTLER 04-21-2009 08:56 PM

:lol: :lol: :lol: GOT YOUR ARM STUCK IN THE HEADER :?: :?: :?:


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