Roller Rocker Problem on GEN I any help is appreciated

[ACELLR8]

I am looking for a little input on what went wrong with my roller rocker install on my 95. I think I asked this a while ago and did not get any help.

Here is a little background. About 2 years ago I installed Crower 1.7 Ratio Roller Rockers on my built Gen I. Car has been running perfect ever since with out any issues. The problem is I lost about 40 RWHP from the swap.

Before the change my 95 was making 469 RWHP and this was confirmed on two seperate dyno's. Now my car is making 429 RWHP and the same thing had it dynoed twice since on two seperate dyno's.

My car has heads with 2.02" intake and 1.60" exaust valves and a crower stage I cam (lobe lift .330/.343, Gross lift .528/.549).

At first I was concerned that I over tighted them when I installed them, but I was told if they were over tightened the car would be running poorly. Also have been told to just leave them in place even if I lost HP since it is a better roller rocker.

So, I wanted to try and get some input from the smart engine folks here (obviously I don't know to much about engines). Before I take them out this weekend and put the stock rocker arms back in and sell these on Ebay.

Thanks,
Ed

 

[ViperTony]

When the rockers were installed, did you measure/check push rod length? Maybe the wrong length push rods are installed. With my stock engine, I had to measure and install new push rods when I installed my T&D's last year since the stock push rods were a bit too short. I'd suggest getting your Viper to a Viper Tech and have them check the rocker/push rod install. Can't hurt.

Wouldn't over tightening cause valve float which could lead to a poorly running engine? FWIW, there's a roller rocker adjustment procedure in the illustrated section by JackB. In it, is a very handy chart on adjusting the rockers although it's for T&D's the cylinder reference chart and TDC procedures are very helpful.

Last suggestion, try calling Chuck Tator. Maybe he can give give you some ideas on what to look for.

 

[PaViper]

You can use the valves from a Gen III, I understand they are the correct length for using rollers

 

[99 R/T 10]

You can use the Roller rockers from a Gen III, I understand they are the correct length for using rollers

Second that. The Gen III RR are much better than the Crowers. Get rid of those if they aren't shaft mounted.

 

[plumcrazy]

call greg good and see what he says.

any other issues ?

 

[mbccenter]

Your engine and cam design does not like 1.7 rockers. Need to change to factory size or ?

 

[Bolt]

Someone correct me if I am wrong. I was under the impression that when going to a roller rocker you must run a different valve length to compensate for the roller on the tip of the rocker. I guess the valve would be slightly shorter. This would keep the geometry correct for the lift. I assume you could achieve the same results by swapping out the pushrods to compensate for the roller. Either way we are talking about a small amount of distance and maybe this is why your car is running great but under extreme conditions that little bit of lift loss could be showing up as loss HP. Maybe someone else can chime in and help out.

 

[Jack B]

Someone correct me if I am wrong. I was under the impression that when going to a roller rocker you must run a different valve length to compensate for the roller on the tip of the rocker. I guess the valve would be slightly shorter. This would keep the geometry correct for the lift. I assume you could achieve the same results by swapping out the pushrods to compensate for the roller. Either way we are talking about a small amount of distance and maybe this is why your car is running great but under extreme conditions that little bit of lift loss could be showing up as loss HP. Maybe someone else can chime in and help out.

It has already been stated, you have to start from base one and measure the required push rod length. If tis was not done the odds of you getting correcting geometry and adjustment are very low.

 

[01ACR/VIPER]

Second that. The Gen III RR are much better than the Crowers. Get rid of those if they aren't shaft mounted.

The genIII rockers are roller fulcrum only...no roller tip.They are also designed to be locked down,non adjustable.I did the swap on mine and they worked ok but were noisy as hell.The crowers are fine rockers(not as nice as t&d and such...nore near as much viper tax)You will need a different length pushrod.I think mine are 7.550 long.

 

[ACELLR8]

Thanks guys for the responses. Slowly trying to learn about the basics of Valve train technology.

Greg Good has been PM ing me some good advice. Gonna try and get in touch with him to determine what the problem is or whether I need new length push rods.

thanks
Ed

 

[ViperJohn]

Hope you get this worked out Ed. I would suspect the valves aren't opening all the way causing the loss in power. I also haven't heard good things about Crower rockers.

 

[01ACR/VIPER]

Hope you get this worked out Ed. I would suspect the valves aren't opening all the way causing the loss in power. I also haven't heard good things about Crower rockers.

Oops,my bad...I was thinking Harland Sharp.I do know of people using the Crowers on 5.2 and 5.9 mopars.The bad thing is that they can jump off the valve if a serious over rev occurs.

 

[RedEnuf93]

I think the pushrods are too long, your valves are opening to much...
Get shorter rods, so I can beat you more....