how much compression for stock starter?
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Elder User
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From: UTI student
how much compression for stock starter?
How much compression can the stock starter handle before you have to upgrade? Do I just throw the stock one on and see if it will crank and if it does then I'm ok?
Post Fiend
Joined: Jan 2003
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From: Iowa
Yeah just throw the stock one on. It's not how much compression you have, it's how much cylinder pressure you build when cranking. The cam has a lot to do with this. You could build a 10:1 motor that would crank over nice and fast with a big cam, but would crank over slow with a small mileage type cam.
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Elder User
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From: UTI student
Ok so it's safe to say that just because I have 8.5:1 doesn't mean my starter can handle it? I set my timing to were the motor runs really great and no appearent pop through the carb but it slowly cranks and won't start when I shut it off. Am I building too much cylinder pressure? Is that bad?
Post Fiend
Joined: Jan 2003
Posts: 8,600
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From: Iowa
At 8.5:1, you'd need a REALLY small cam to make the stock starter not handle it. I'm talking, like, 2 sizes smaller than stock. Timing can make it crank slow, if the timing is advanced far enough. Where do you have yours set?
Right now, I'm kinda thinking your starter is worn out. How are all the electrical connections to it? A loose connection can make it crank slowly, or not at all in some cases.
Right now, I'm kinda thinking your starter is worn out. How are all the electrical connections to it? A loose connection can make it crank slowly, or not at all in some cases.
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Elder User
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From: UTI student
I set the timing at 10* but with the carb making a slight pop at that setting I'm begining to think my marks are off. It was a recon crate short block so I wouldn't put it past them to run a really small cam. The connections are good but the starter is almost 2 years old.
Post Fiend
Joined: Jan 2003
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From: Iowa
They probably use a reproduction stock spec cam. To check the timing marks, find TDC on number 1, then compare it to the location on the damper. If it's off, it is likely that the damper slipped, in which case you should get a new one.
FTE Leadership Emeritus
Joined: Jul 2002
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From: Long Island USA
Sounds like you have the initial timing too far advanced. Does it do the "whir whir whir" thing?
Once the engine is hot, the rings seal REALLY well, and the starter can't get past the point where the spark plug fires.
Once the engine is hot, the rings seal REALLY well, and the starter can't get past the point where the spark plug fires.
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