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CROWN MAN

12-09-2004 01:58 PM

Big Block

On a 1999 454 mpi with 200 hrs. What should the compression be?
How many HRS. should it be good for, on average? More than a 1000 or less?

Dave M

12-09-2004 02:03 PM

Re: Big Block

I think your compression should be around 150 psi. My 454 Mag puked after about 550 hours. Keep an eye on your riser/manifold gaskets. That's what killed mine. I ran in salt a lot and ran hard.

articfriends

12-09-2004 02:24 PM

Re: Big Block

150-160 psi

Edward R. Cozzi

12-09-2004 10:51 PM

Re: Big Block

Consistent numbers among cylinders is important too.
Don't be alarmed to find 140s.

CROWN MAN

12-10-2004 07:34 AM

Re: Big Block

Should the motor be at temp. when checking?

Griff

12-10-2004 12:05 PM

Re: Big Block

Quote:

Originally Posted by CROWN MAN

Should the motor be at temp. when checking?

Yes, and throttle at wide open.

CROWN MAN

12-10-2004 01:19 PM

Re: Big Block

So the motor at temp then W-O-T then check?
I`ve never heard about the throttle. what does it do?

Griff

12-10-2004 01:39 PM

Re: Big Block

If the throttle's not open, air can't get in. If air can't get in, it can't get into the cyliders to compress.

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