New Motor Ignition Troubles....
Thread Starter
Pro
Joined: May 2010
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From: Pennington NJ
New Motor Ignition Troubles....
Ok....so my GM crate 290 HP is installed and ready to run. At first the distributor was 180 degrees out, so I corrected that. Not sure what I put the timing to but it started up immidiately but wouldnt rev at all. Like any throttle position was the same basically about 700 rpms. I tried advancing the distributor (maybe too much). It didnt seem to help, so I advanced it more. It eventually got to the point where it backfired out the carb. So I went the other way, where it started to not run at all, and backfire out the exhaust. I have a Mallory tach driver breakerless distributor, new everything and vacuum advance hooked up.
What should I do? Should I disconnect the vacuum advance for now so its just "straight" timing? And is the timing that sensative that I might have just passed the sweet spot? I dont remember a SBC being like that but?
I'm doing the break in so I kinda just want to get this thing going to 2000-3000 rpms right away, all of this messing around isnt to my liking...
Please let me know what you think.
Thanks,
Will
What should I do? Should I disconnect the vacuum advance for now so its just "straight" timing? And is the timing that sensative that I might have just passed the sweet spot? I dont remember a SBC being like that but?
I'm doing the break in so I kinda just want to get this thing going to 2000-3000 rpms right away, all of this messing around isnt to my liking...
Please let me know what you think.
Thanks,
Will
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I think I'd pull the number 1 plug, bring the cylinder back up again and verify you are not a tooth out.
Next.. I'm not sure but I believe the Mallory requires 12 volt constant voltage to run... if you used the old resistance wire for the 12 volt supply to the distributor you'll need to change this to a constant 12 volt switched supply.
After you check the number 1 again.. and it its 1 tooth off, try again. If it's not then post back.
Next.. I'm not sure but I believe the Mallory requires 12 volt constant voltage to run... if you used the old resistance wire for the 12 volt supply to the distributor you'll need to change this to a constant 12 volt switched supply.
After you check the number 1 again.. and it its 1 tooth off, try again. If it's not then post back.
Burning Brakes
Joined: Oct 2001
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From: Okinawa Okinawa
Are you manually reving the engine with your hand via the carb or in the car doing it with the pedal? Stupid question but do you have the linkage set up correctly if you are using the pedal. I don't know anything about Mallory ignitions so I can't help with that. Verify you are getting a shot of fuel when you work the carb. If so, it very well may be the ignition box isn't hooked up correctly.
Sounds like you may be one tooth off like Willcox says. Double check everything before the next start up so you can get it up to 2000K as quick as possible.
Sounds like you may be one tooth off like Willcox says. Double check everything before the next start up so you can get it up to 2000K as quick as possible.
Thread Starter
Pro
Joined: May 2010
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From: Pennington NJ
The pedal linkage hasn't changed, just how its been for the life of the car. This model Mallory distributor (57 series) states that it needs the resistance loom wire and instructs just to hook up as original.
I think it is off a tooth. When I brought it to exact 0 degree TDC, The rotor was to the left of the #1 cylinder, not to the right, so I think it was one tooth retarded. I had a brain fart haha. I'll bring it back to TDC and then reset the distributor with a little advance, not retard this time. It should work then...
I'll let you know how it goes
Will
I think it is off a tooth. When I brought it to exact 0 degree TDC, The rotor was to the left of the #1 cylinder, not to the right, so I think it was one tooth retarded. I had a brain fart haha. I'll bring it back to TDC and then reset the distributor with a little advance, not retard this time. It should work then...
I'll let you know how it goes
Will
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Yeah the rotor should be pointing past the #1 tower, when the balancer points to number one on the timing tab.You are one or two teeth off,
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Pro
Joined: May 2010
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From: Pennington NJ
Ok you guys were correct! I reset it to TDC and set it to 12 degrees *advance* and it fired right up and we broke it in successfully. Thanks for all of the help. Once it is done, I'll post up a thread on the motor swap.
Will
Will
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Glad you got it started an broken in, 
I wish more people that come here ask for help give some feedback on the results they get, but it seems the attitude is, I got it fixed I don't need to thank anyone, I don't think this mindset will ever change
I wish more people that come here ask for help give some feedback on the results they get, but it seems the attitude is, I got it fixed I don't need to thank anyone, I don't think this mindset will ever change
