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Author Topic:   first engine build
Racer8c
Member
posted May 26, 2003 01:56 PM
OK, here's my problem......ever since I built this engine I can't seem to get it to run good at low rpm, it sounds like it's off time at low rpm, which my cam makes power between 3500-7000 rpm, but I can't even get it to power brake to check the posi unit I got from the junk yard to make sure it's working right. I've put a accel super coil, accel modul, new wires and plugs(several heat ranges and gaps) even switched distributors to make sure it wasn't a wiring problem. I put distributor on seperate toggle switch, getting 12.6 volts, adjusted valve lash several times, put on different carburetors, different jets, it just don't have any power at all at low rpm. I don't think I have a vacuum leak, at least I can't fine one by spraying wd-40 around intake, the only thing I haven't checked for is bent pushrods or valves, total timing is 36 degrees at 2500 rpm, I cut off vacuum advance and welded it to the distributor housing to block any vacuum advance. I'm running a midwest cast iron intake meant for spreadbore with a 1" adapter plate for Holley. I'm not running a stall converter to get the rpm's up before I take off either, don't know if that would cause anything like this or not. I'm out of things to check for, anybody else think of something I'm missing or is it just suppose to run like this. This is my first engine I've built so I need some help.


racer1030
Member
posted May 26, 2003 05:51 PM
Check your cam timing. It sounds asif it may be retarded a tooth.


towmandan
Member
posted May 26, 2003 05:59 PM
Other than cam timing the only other thing I can think of is to much cam shaft for the compression your running... it can make one very doggie at lower rpm...Once you get it up in RPM it doesnt seem so bad cause your in your power range...My guess is theres not alot you can do on the outside....Towman


rico 08
Member
posted May 26, 2003 08:45 PM
check you're cranking compression.


Racer8c
Member
posted May 27, 2003 09:42 PM
My compression is 10.5 to 1 according to my machinist, and my cam was installed straight up. I bought this cam because of the power in the rpm range I wanted to run in on a half mile high banked track(around 6300) haven't actually checked compression myself though.


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