Ok. I transplanted a 88 Renix 4.0 into my 81 CJ7 5 years ago. I got it running pretty good and just drove it around logging 20,000 miles. But, it has always nagged at me that I wasn't getting everything that the 4.0 should be putting out. 3 weeks ago I dove back in to try to find out what my problem was. First of all my timing at warm idle was 20 deg BTDC. This is wrong as it should be at 10-12 deg BTDC. So I started at the signal that starts everything off. The crank trigger ( usually found on the bellhousing that triggers off of the flywheel ) is the start of things. I have a Hesco Harmonic balancer trigger on my transplant. It is a mini version of the flywheel and triggers the same way. My problem is that with the motor at TDC the sensor for the crank trigger should be over the 12th tooth after the large gap. Mine is not. It is over the gap between the 14th and the 15th teeth after the gap. What this is telling the computer to do is fire the electrics before the mechanics are in proper position. This difference of 2 teeth is 10 degrees on the balancer. Now I can't get an answer from Hesco so I'm hoping for some help here. Why would Hesco cut their balancer advanced this much??? What good does having the computer trigger all events 10 deg before the mechanics are ready for them?? Does anyone here have a hesco balancer that the could check for me?? BTW. This is a new balancer. I sent my old balancer back to hesco last week. They told me that I had a performance cut balancer and needed a STD cut balancer. When I put this STD balancer on last week it did run a little better but still shows 20 deg BTDC. Why could this be. Thanks Ben

This might be what is fawkin with mine. I did mine with my auto swap and it just never seemed the same.I will do some checking on mine

I didn't know that Hesco made the balancer for the Renix version, as the number of teeth are different.

Hammerman. Please check for me. There is a long thread I started on the strokers site about this with a lot more detail with Bennie from Hesco even joing the discussion. He doesn't seem happy for this to be discussed openly. As for the Renix HB yes this one has 60 teeth and the HO version has 12.

I've had several Hesco balancers (both Mopar and Renix) either "slip" on the hub or be incorrectly assembled, and the result is always incorrect ign and injector timing. I usually end up modifying the bracket to get the correct timing.
BTW, I have a shop and do a couple of 4.0 swaps a year on average.

rbaer. Am I correct that the sensor should be positioned over the 12th tooth when the motor is at TDC???? My renix manual says so but Hesco seems to be blowing off the fact that mine is over the gap for 14 and 15. This is the second damper from them and they were both this way. And also what is the timing supposed to be with a light at warm idle??Thanks Ben

Maybe it's off one tooth on the timing chain.

nope. I pulled the front of the engine off last week to re check this. All is good with the internals. Even if it was this would not have any eeffect on the timing per say. It would make it run worse but as long as the distributor was indexed correctly ( and mine is ) the timing would look OK. Thats the problem, my timing is 20 deg btdc using a light. The cps starts this whole process off. In looking at the Hesco balancer it appears to be wrong. Thanks Ben

anybody?????????