1.6 Roller Tip Rockers

[Cooki_monstre]

I have a 96 LT1 Impala with PRW 1.6 roller tip rockers. The thing doesn't run right and I'm getting rid of it

Thing is, I still have the old rockers from that vehicle. I could throw those back on and put the 1.6 rockers in my 98 Astro
I'm planning to also remove the restriction on the throttle plate, likely tomorrow.

1. Has anyone else put 1.6 rockers in their van? Is there anything special you had to do? Any other parts I should order?

2. When I rebuilt previous engines the lifters were all empty so I could simply tighten the rockers until the pushrod just started to drag (zero lash) and then ad the 3/4 turn. The LT1 was perfect when I did this, but the Astro is my daily. Is there an easy way to adjust preload when the lifters are all pumped up without running the engine? could I possibly do it the same way?

3. Will I run into clearance issues with the valve covers?

Thanks for any help

[chevymaher]

Your astro does not have adjustable rockers. Nut bottoms out on the stud. So many lbs TQ done. You would have to look to see if they are compatible. They may just be.

[TowVan]

Member JD_GM was doing a complete rebuild of a 99 4.3. Using a 95 (most aggressive of the stock cams) and 1.6 rockers. He had to (or did) enlarge the pushrod holes for the larger angle. Also needs screw in stud kit, but that's the easy part. He has not posted any updates in a while.
Yes, They are the rockers that will fit, but needs additional parts/work.

[Cooki_monstre]

So it looks like it is too much work right now. It is true, Comp Cams make a 1.52 roller tip rocker set for the 4.3. I guess the thing to do would be a cam swap with those roller tip rockers for reduced friction and a better, more accurate valve train angle. Don't have the time for that right now, but perhaps one day I will build a 4.3 because I've always wanted to build an engine most people don't build. Thanks for all the input everyone.

I did however contact PRW with the question and found this videohttps://www.youtube.com/watch?v=LVJOACVJIQE theoretically it's possible i just have to ensure that when I mount the rocker it has the right preload (And then of course check that the pushrod isn't contacting the head in the rocker bore, but I didn't have any issues with that on my LT1 which has an extremely similar head design)

[dcsleeper]

regardless, swap those rockers out of the caprice before you let it go.

[Slime]

Just an FYI, I put a Compcams 206 hydraulic roller cam in my 4.3 When we tried to start it, it wouldn't start. Got to checking and it was pulling the studs out of the heads. I had some work done to the heads but didn't figure it would do that. Took them back to the machine shop and had screw in studs installed. Apparently, they are a worse press fit than a V8...YMMV

[chevymaher]

I am sure glad i got the unrefined older model with screw in studs.

[dcsleeper]

yeah I don't understand.
The early heads had 10mm threaded studs and the vortec heads had 8mm metric threads.