Printable View
My builder asked for my input. 427 Modified Motor, Dart 200cc Heads, 500 Holley, 8" Wide Modified Tire on Asphalt we are sure if we will be making Cam changes or Needing to retard it so its why we are asking, He asked me if I wanted a Belt drive or Chain driven, he said a belt would be easier to change cam timing, but wasn't sure if that was overkill for my application. What are the pros and cons are they in circle track modified motors
I have used both , both have there advantages , degreeing cam is easier on belt , but cost a lot more , for the most part on an engine like you are talking about , we stick with the chain....
I vote for a chain... Get an iwis chain as they are pretty tuff...
Years ago, I spent 1200.00 to buy an Jesel external dry belt so I could easily adjust the cam timing without having to remove anything (even the water pump) on the dyno. My thinking was I could possibly find an adjustment to remove some bottom end and/or add top end when the track changed.Quote:
Originally Posted by 7uptruckracer
Long story short I got more what I wanted off ignition timing then changing the cam timing, cam timing killed power more evenly thru out the entire RPM range where ignition timing effected lower RPM more and didn't change the higher RPM as much. After testing it, I concluded it was not worth my time for what I wanted to adjust the cam timing and more easily done with ignition and produced a better result.
The external belt also had an small idler bearing that was notorious for failing due to the small size which made it's RPM several times over the engine RPM, thus the reason for early failures. Then add in the open belt that was susceptible to dirt and debris.
Thanks guys good info. I appreciate it