Ok. I have a problem. Here it is. I trapped 3 12.0 runs. All of them were at 111mph! That is extremely low mph. I have Comp R lifters, and heads milled .030 with a 224/224 563/563 114 LSA cam. I run stock length pushrods. I have heard that the preload needs to be adjusted on the Comp R's. I didn't do anything to mine but install them.

So, I have heard that running shorter pushrods will help me out in the mph and ET. Is this true? I'm asking the pros.

For more info, my car is an A4 running a 3.73 gear. I don't think this will cause the mph to be that low. I should be trapping 115-117 area. If you have any questions, ask me please. I want to resolve this problem. Thanks guys.

 

Only way to really get the preload right on the Comp Rs is adjustable rockers. However, my Jesels are non-adjustable on my MTI motor so MTI must have shimmed them. I'd call up MTI and ask what they do.

Improperly set lifter preload, as in the Comp Rs, will definately decrease your MPH b/c it affects your valve events.

If I were you'd I just take the heads off and swap stock ones on. We still have your old ones at Alex's place. It'd be a heck of a lot easier and would be less of a headache.

 

I have thought about selling my heads in the summer and getting a set of used unmilled TEA heads. I want 2.02 intakes and port work with a G5X2 cam through the LSX. I will have to wait until the summer before I can molest my car for days on end though.

If I don't want to sell my heads, but pull them, I will just put stock lifters back in.

 

I'd just put the stock lifters back in, I really think it'd bump your MPH way up.

I was gonna ask you about that after I found out you had Comp Rs. Your heads are awesome, I wouldn't get rid of em'

 

What did ur car dyno? If u dyno's anywhere over 360rwhp then u should check other componets than the engine........... This happend to me and after a month i found out that its a brake problem, not a engine problem especially since i dyno'd 392rwhp 382rwtq.....................Check ur front calipers and brake oil. It never came to me when i was dissapointed with the 114mph i trapped at and after a month or so i found out that my front calipers was holding the pads against the rotors the whole time.

 

Dude, I guarantee that my car is over 400RWHP. I have no brake drag either. That would be a very evident problem. Smoke, smell yada yada yada.

 

IMO, it's the lifters that are costing you power, Matt.

What you should do is pully your valve covers, turn the crank until both valves are closed on any given cylinder, loosen the rocker arms, up, tight the rockers until you can no longer spin the pushrod by hand, once you hit this point, count the amount of turn that is required to hit the torque of 22 ft-lbs, then we can go from there to determine your current preload