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Help! i just had the motor rebuilt. the rad is clear. my mechanic is trying to tweat the timing. the transmission is 2 speed. while idling and driving up to 60mph, it runs great and heats up to say 210degrees F.
after 60, if i try to push it harder, i get the bag of marbles sound and the temp starts climbing up to 250 F or higher. my mechanic says if i switch to electronic ignition it might help, plus it will be more reliable..?
any one have any thoughts on this issue? do you agree with him, and if so, any suggestions on what type to install?
 

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I would check the timing, could be a problem with the mechanical or vacuum advance. I have the crane cams XR-1 Ignition Conversion Kit on my cars to retain the original look. It replaces the points and has an adjustable rev limiter.
 

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Did you check the t-stat? Is the waterpump correct for your car? Are the plates installed, and correct? What fan are you running? Do you have a fan shroud? Are the seals in place around the shroud and radiator support? Are you using the correct radiator? Are you using QUALITY hoses that won't collapse when they get hot?.......Eric
 

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What compression ration are you running? If you're running stock heads and stock type (non dished) pistons, It will ping like crazy. Electronic ignition won't help. You'll need higher octane gas, a lower compression ratio, or to back off your ignition timing quite a bit. I had the same problem with my '67 and went to lower compression heads. With my '65, I run a big cam, a stickshift, and octane booster. Hope this helps.
Jeff
 

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Discussion Starter #6
Help! i just had the motor rebuilt. the rad is clear. my mechanic is trying to tweat the timing. the transmission is 2 speed. while idling and driving up to 60mph, it runs great and heats up to say 210degrees F.
after 60, if i try to push it harder, i get the bag of marbles sound and the temp starts climbing up to 250 F or higher. my mechanic says if i switch to electronic ignition it might help, plus it will be more reliable..?
any one have any thoughts on this issue? do you agree with him, and if so, any suggestions on what type to install?
Alright, these responses are great. i now have some ideas to try going over with my mechanic. thanks guys, very much appreciated. i will let you know how it is turning out.
bb
 

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What compression ration are you running? If you're running stock heads and stock type (non dished) pistons, It will ping like crazy. Electronic ignition won't help. You'll need higher octane gas, a lower compression ratio, or to back off your ignition timing quite a bit. I had the same problem with my '67 and went to lower compression heads. With my '65, I run a big cam, a stickshift, and octane booster. Hope this helps.
Jeff

Jeff, what type of octane booster do you use and will the supplier ship to your home? Thanks, Paul.
 

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Paul: I'm using something called TEL 130. It's for off road use because it's LEAD. Google TEL 130 and you may
d it. I had a case shipped to my house maybe 3 years ago. Not cheap, but it works and it IS cheaper than pistons!!! In my '67 with the 670 heads and then the 12 heads, NOTHING worked. (but I didn't try the TEL130, either). I ended up installing some #15 heads with the 87cc chambers, and it runs well and now has about 9.2:1 compression. It doesn't have the chutzpah it had with those 670's, though! Big inches and high compression ROCK!
 

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Paul: I'm using something called TEL 130. It's for off road use because it's LEAD. Google TEL 130 and you may
d it. I had a case shipped to my house maybe 3 years ago. Not cheap, but it works and it IS cheaper than pistons!!! In my '67 with the 670 heads and then the 12 heads, NOTHING worked. (but I didn't try the TEL130, either). I ended up installing some #15 heads with the 87cc chambers, and it runs well and now has about 9.2:1 compression. It doesn't have the chutzpah it had with those 670's, though! Big inches and high compression ROCK!
Thanks, I'll give your stuff a try to see if I can keep the 670s. Yesterday I saw an octane booster in a Connecticut auto parts store and the label stated that it was not "legal for street use" and was not permitted to be used in California. I almost bought the stuff based on those two "recommendations."
 
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