Thats what we have on the GTP & SSEi. (funny how the GTP is the fastest stock cam L67, yet it doesn't even have roller rockers) Well, the GTP has ZZP'* 1.9:1 rocker arms, but they were made by the same company that is now making the I-Win that are listed there. Then ZZP stopped carrying them about 2 years ago, and 3800 Performance started selling them as the I-Win rockers a couple months later. We bought the first set of them that 3800 Performance sold and put them on the SSEi.

There is really not that much friction made between the little contact surface there. Plenty of oil is flowing up there even with the OR pushrods, if there wasn't plenty of oil flowing up there then it would be a bad idea to use those pushrods. I know when we pulled the rockers off the GTP to put the springs in, the rockers & pushrods had been in for 8k (not a lot but still some miles) and they still looked like brand new.

No, because you aren't increasing duration very much at all. You are increasing lift a lot, but stock L67 heads don't flow that well at much over the stock lift, so really what you are gaining is mainly from the faster opening valves, but still a little from the extra lift. Stock specs for an L67 cam are:
.255 Intake (.408" valve lift stock, .485" w/1.9 rockers)
.258 Exhaust (.413" valve lift stock, .490" w/1.9 rockers)

However, take a look at this dyno sheet from a decently modded '02 GTP:
Blue line is aftermarket cam, red line is stock, green line is 1.9 rockers:


In his fairly heavily modded car the rockers didn't even make much difference. I have found they make 10-15whp on just about every application, no matter how modded. And the cam gains there are promising, however you have to remember that a cam is a LOT more work and definately requires at least different valvesprings, but the pushrods really should be replaced as well. I would recommend a cam for anyone who wants to get really serious, but based on what I have gathered from his posts, silverbullet isn't looking for a race car, and I don't think I would tear into a low miles engine like that either. IMO rockers are perfect for what he wants.

Shawn

Good info Shawn. So how do you explain INTENSE'* claim of 23 whp with just the 1.9 rockers. :?

I just may give the I-Win'* a go......even if you say it'* only worth 12 hp, I'm optimistic that I may get a little more.

Aha. My hypothesis was right, I just noticed that the torque actually decreases by 10 ft-lbs with the 1.9 rockers. :?

Intense'* claims are based off of Rogue'* Dyno'*....

I've driven his car with rockers, it was nice, made smellbirds go faster nicely as well.

However a nice set of heads and a cam would be very beneficial....

How do you end up losing torque from that? That right there turns me away.

They claim that the torque difference is due to swapping out motor mounts at the same time I guess...

Shawn

This is interesting. Motor mounts! What does that have to do with it. :?:
Can anyone else with 1.9 rockers step in and give us their experience with the 1.9 rocker swap with regard to torque loss of low rpm <3000 rpm. :?
An actual loss of low end torque is not good for everyday driving. Might be OK for racing where the engine is always up over 3000. rpm.
Of course, our cars are torque beasts already....and it could help traction, not to mention trani life (but that'* a stretch).
There is good reason why true racers install a 3000 rpm stall torque converter.

Here is a whole page about the 3 dyno pulls. That way you can make your own conclusion.

http://www.3800performance.com/cc_xt...7_cam_dyno.htm

I've never noticed a torque loss and I've done quite a few rocker swaps, but thats probably because they have so much torque to begin with. The torque loss isn't noticable if there is one.

I don't know how to explain it other than every car is different, because the car that did that dyno had INTENSE rocker arms on it. I know this because there was a big post about it on ClubGP. People were getting pissed at INTENSE for something, stealing a pic or something stupid like that, and Luan got all pissed off and said that was it, he was done with intense parts and he was pulling them all out of his car. So he took out all the intense parts (rocker arms being one of those things) and replaced them with other parts, in this case he installed a cam instead of Intense'* rockers. But he did have previous conflicts with INTENSE that I don't want to get into right now, so I can almost understand why he did that.

Shawn

Different cars explain minor variations but this is a 100% difference.

Lift is lift.
The only difference between the two brands of rockers is the friction reducing rollers and a slight weight advantage.

In the long run you'll wish you had the lighter, roller rockers. They'll last longer, run smoother, and aren't cutting corners. I know your gonna keep that car a long time, and wanna keep building her up, so think about the future. Why not hold off till you can get what you want?