Cranking Pressure?
 

I just checked my cranking pressure with a compression gauge. And was shocked by the number (close to 300 pounds). The motor starts up fine without bucking. And seems to make good power, picked up 3+ mph over last years motor.
This years motor has 14.5 to 1 compression and 30 more degrees duration in the cam, than last years 12 to 1 motor.
Should I be worried about the high number?

Re: Cranking Pressure?
 

Holy smokes Art, last time I had that Crank Pressure was on a flat track bike that broke my foot when I was screwing around and wanted to start it "one last time" before I went to dinner (not wearing my boot).

I really dono. were at 220-218 on ours at about 12.5:1 so.....If that helps any.

Re: Cranking Pressure?
 

I wonder if my hydraulic lifters are collapsing a bit decreasing cam lift and duration, when I test the motor. I almost can't believe the numbers. The motor starts to easy and runs well.
What does cranking pressure effect?

Re: Cranking Pressure?
 

And runs records :D:D:D

Maybe this will help, I dont know if the calc is in Pipemax, I dont have it on this computer

http://www.not2fast.com/turbo/compre...pressure.shtml

http://www.chevyhiperformance.com/te...ion/index.html

Re: Cranking Pressure?
 

Thanks Chris I saw those sites. Right now I'm wondering if there is something going on with my lifters. It just doesn't make sense that I could have such high compression numbers and stil have the car run the way it does.
The gauge is a brand new gauge so I'm going to borrow one and see if it is the same.

Re: Cranking Pressure?
 

What with your bore stroke and duration did it come to on the calc if you dont mind me asking ?

Re: Cranking Pressure?
 

Hi Art, cranking pressure CAN be affected by your lifters not pumping up. I would say that 300 psi is too much but then I was taught to try and keep cranking pressure "more than 160 and less than 210" and I could have been taught wrong. When I was running really high compression Bracket stuff (15 to1) I was only winding up with about 210 but I was using pretty big cams.
If anybody has any other opinions I'd like to hear from them.

Re: Cranking Pressure?
 

Billy I tried retarding the intake cam 6 degrees (dropped the cranking pressure to 270)
It slowed the car up. Put the cam back and I got the power back.
I had to change the timing offset. when i retarded the cam.
Then I had a brain fart and forgot which program I had in there (there are 13 different fuel curves). It took me 5 runs to figure it out, wasting a test and tune day.

Re: Cranking Pressure?
 

Art, did you check it with a plugged lifter yet?

Re: Cranking Pressure?
 

No I have just come to the bare fact that it it's running right don't mess with it If you do You will find something wrong.
The motor is making great power I still am close to getting in trouble with me shifting 1500 short. Even I am wondering "where the turbo is hiding"LOL
I seem to have worried myself silly (something I'm real good at) for a couple of weeks for nothing.
It's like the movie Dr Strangelove, or How I learned to stop worrying and love the Bomb.