When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
71 350/270hp
I would like to repalace the stock harmonic balancer (8"x1 5/16") with a high performance one (8"x1 11/16"). What modifacations would I need to make?
Bumping this to the top to see if anyone has a deffanent answer to my question. I would like to know for sure that it would bolt up without any modifications for the pully or the timing pointer.
Believe there is a company called Fluid Dampner or a brand name like that which is supposed to be a pretty good bolt on dampner. Also believe some of these aftermarket dampners may have 360 degree timing marks, so no need for timing tape.
Tom,
I have a '71 270 horse motor. The ballancer was 6 3/4". I believe the LT-1 had the 8" balancer. (someone with a real LT-1 can check for you)
Either someone installed an LT-1 8" ballancer with the correct tab, or some one installed an LT-1 motor! :cheers: :yesnod: :cheers:
The timing pointer coincides with the diameter (circumference) of the balancer. So if you are already using an 8" one, the pointer will work.
As for the pulleys, the thickness of the balancer increases front to back (i.e. the thicker one will have less of a gap to the timing chain cover) so the pulleys will remain in the same position.
Just curious, what do you hope to gain with the change? Unless, your original one is damaged, the inertia ring has shifted, or you're running a super high revving motor, the change to the HP version will have little or no effect on anything.
The question I'm adding is that if it has an LT-1 ballancer, he already has the good ballancer, right?
Maybe it's an LT-1. Wouldn't that be a good find.
The balancer I have has a slight wobble to it. I figure if I am going to replace it might as well go with a higher reving one. That way I know it won't seperate on me when I rebuild a higher horse power motor. Thank you for all the information guys. This really is a great forum.