benelliwang

Well, my new engine has piston to valve clearance issues and I am trying to find to what to do next. In the process I’ve called several shops and my checking technique came up and each gave me difference recommendations:

Thunder Racing: Recommends Solid Lifters, but test springs with hydrolic lifters are ok. However test springs will not be as accurate as Solid lifters.

Crane Cams: Test springs are more then fine for the work. Solid lifters can’t give proper preload anyway. But they do sell solid lifters, part number 1050-1 at $23.80 a piece.

Comp cams: Test springs are fine. But if you can get Solid lifters, it is also ok. They don't sell solid lifters for LS1. I guess the rep doesn't know SBC lifters from 87 and up are same as our lifters.

A&A Corvette Specialties: Test springs should be ok. Get springs from Home Depot.

Combination MotorSports: Solid lifters are recommended.

Kell’s Automotive Machine shop: Solid lifters or add aluminum washers (WTF? I don’t understand.)

What are your thoughts?

Also, several shops feels that my cam should not be causing piston to valve issues. What are you thoughts? Here is my spec:

Com cam: 226/230 .568/.571 113LSA, smaller base circle. Checked out by cam doctor. The lifter is actually smaller then the spec above by a few hundredths.
A&A stage 1 heads: Currently milled .043 with 2.02” intake and 1.60” exhaust.
Stock short block
TR 7.350” pushrods
Stock rocker arms
Comp 918 springs with titanium retainers.
Stock Lifters: soaked in oil all day.

I did the test with cylinder # 1TDC and without head gaskets. Test springs were used (from HomeDepot). As I move the crank slowly from TDC. The intake starts to hit piston at around 10 to 15 degrees after TDC. The exhaust is hitting 10 to 15 degrees before TDC.

Based on the numbers above, do you think valves should be hitting the pistons? I am gonna do the test with head gaskets again and see what happens.

benelliwang

No one cares?

99 Black Bird T/A

iTrader: (4)

Bene,

Have a chance to test with the head gaskets?

SRP who installed my H & C used a solid lifter and a gauge dial for the check.

BTW are you sure only .043 was taken off of the heads?

LS1derfull

Dude you would definitely have a problem with your set up. Im not surprised if intake and exhaust valves need reliefs cut. The thing that hurts your ptv the most is the larger aftermarket valves and their thicker margins. Don(SLOWHAWK) and I ran into this with his LS6 heads milled .030" with only a TR 224* cam. Culprit was larger thicker valves, i even machined them down to stock valve margin thickness, and we still had to cut reliefs for his intake valves in stock pistons. We used Isky cutter tool worked nice.

benelliwang

You know what, the valves do look kind of big... Thanks, that would make sense for me.

The heads are milled at .040 at first, then .003" during refresh. I used dial calipers to check the height and it checked out.