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Author Topic: Compression  (Read 7352 times)

Offline RickyBobby

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Compression
« on: February 28, 2008, 08:36:19 pm »
So I just did a quick compression check on my motor.  I bought my car near the end of the race season and Dwight Pilgrim from Legends of GA drove my car and said the motor in my car is very strong.  It does pull very hard.  When I did the check tonight it was on a cold motor and I did not open the throttle all the way up.  I got 120 across all cyclinders.  Should I expect this to go up with a warm motor and the throttle wide open?
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Offline MegaMang

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Re: Compression
« Reply #1 on: February 28, 2008, 10:00:24 pm »
When he says cold motor, he means not even turned over for a month...  Cold, no oil circulated, nice dry rings...

I'm going with yes, but I know that he's about to try again with the throttle open to see...

So?  What did you get?

Mike
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If it isn't fun, why are you doing it?

Offline RickyBobby

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Re: Compression
« Reply #2 on: February 28, 2008, 10:27:19 pm »
So I started it to get some oil moving.  It was warmer but certainly not hot.  The oil temp guage didn't even move.  Put the throttle wide open and got 150psi on all cylinders.  So I guess I am good to go.  I am sure if I let it warm up to OT and did it I would be 170ish. 
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Offline thunder938

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Re: Compression
« Reply #3 on: February 28, 2008, 10:35:11 pm »
Is it a 1250 with stock cam timming or a built 1200 with slotted cam gears?  The best I have scene a sealed motor pump with stock cam timing is about 160 give or take and that was new.  If you have a built 1200 with the slotted cam gears the builders try to get the compression real close to the rule by adv. the intake cam. This can not be done on a 1250....
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Dave

Offline RickyBobby

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Re: Compression
« Reply #4 on: February 28, 2008, 10:39:07 pm »
I have the ultimate gem of a motor.  It is a 1200 that has never been rebuilt.  The car came from JR's in Atlanta.  He had bought it for the motor and never got around to doing anything with it.  I think 150lbs in a 1200 never rebuild that only ran for 45 seconds to warm it up is almost as good as new.
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Offline thunder938

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Re: Compression
« Reply #5 on: February 28, 2008, 10:42:51 pm »
For a stock motorcycle motor with a few race nights on it, well.....YOU ARE GOOD LETS RACE
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Dave

Offline RickyBobby

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Re: Compression
« Reply #6 on: February 28, 2008, 10:59:39 pm »
The car was build in 98 and this is the original motor too.  I think I lucked out with this car (knock on wood).  I have to shim the valves and rejet the carbs for Canada but yeah I would say I am good to go racing.  If anyone on here is from Atlanta let me know.  I am bringing the car and trailer down for the NASCAR weekend in October and plan to go racing.
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