98cherrySS

iTrader: (2)

I found 7.250 Crane Cams pushrods in my motor. When I bought the car I was told that the cam was a TR224... Thunder racing says I should run 7.400 PR. Also installed when I purchased this car were Crane "Quick-Lift" 1.7 roller rockers. According to Chevy High Performance, the pushrod length does not change when running the Crane rockers.

Anybody run 7.250 pushrods? What cam do you have?

TRANS-DAD

iTrader: (1)

don't won't to get into the whole pushrod length theory, but heads were probably
milled when they did cam and this will change pushrod length

WhiteRhino

iTrader: (6)

The Crane rockers come with those pushrods. The pushrod mating point is located lower on the Cranes vs. stock. So the need for shorter pushrods. If you're going to reuse the rockers you need to use the shorter pushrods. They are adjustable anyway. So you have some leeway.

corvet786c

iTrader: (6)

I have those pushrods now in my car. i am running a vinci there xxx cam 222/228/115. Nice streetable alot of torque.

http://www.vincihiperformance.com/CA...%20LS1%202.htm

PREDATOR-Z

Correct.

98cherrySS

iTrader: (2)

Thanks guys... Then I likely do have a TR224 as it's characteristics are the same as it's description.

I have a tick coming from the headers and I'm thinking it's from the RR's. My stethoscope keeps pointing me towards the valve covers. It improved after I reinstalled the RR's at two full turns. Still there though.

With the valve covers off, I can wiggle the rockers and recreate the ticking noise. They wiggle just shy of a 3/16th inch. The pushrods also show a little wear from the guide plates.

Anyone have any experience with these? Were they quiet? Any similar issues?

Thanks.

98cherrySS

iTrader: (2)

Bump.

vettenuts

iTrader: (4)

They will wiggle side to side slightly. Wear on the pushrods is likely just the coating. Two turns is 0.132" preload, that is way too much. Lock them at 1.5 turns. Have you examined the valve covers for contact?

98cherrySS

iTrader: (2)

I have pulled the rockers and will reinstall at 1.5 turns... BUT - Upon further inspection, I have discovered that a few of the lifters are "soft". As I attempt to set zero lash I notice that I can push down on the pushrods and they compress maybe 1/8th - 3/16th. This is only apparent on a few so far. I will continue to rotate the motor to see if there are any more like this.

My assumtion is that this is not normal. Somebody please chime in on this.

My plan is to adjust while the motor is running. Anyone see any issues with doing it that way?

vettenuts

iTrader: (4)

You can't judge the lifters by backing them off from a partially compressed state and then looking at how much you can compress them. They can't re-fill with oil unless there is oil pressure so they will be soft for some distance.

98cherrySS

iTrader: (2)

I had this thought but wasn't sure about it. I thought the lifters would retain most of their hardness even when drained. I buttoned it up last night and started her today. She made a lot of racket at start up but settled down after a few minutes. Still noisy as hell. I'm going to run her for a while then re-evaluate the travel in the lifters.

I do appreciate your help vettenuts. You helped me last year when I re- installed these for the first time.

disc0monkey

iTrader: (10)

loosen all the rockers and let it sit for a while so all the lifters will return to their natural position. then adjust. or you can do it with the engine running...
this is a good article.

http://www.classicfirebird.com/hand/jhand7.html
its directed toward pontiacs but if you change the preload specs to what your supposed to use then you should be good