Valve to piston clearance?

[joeoby78]

Does anybody think I may have any valve to piston clearance issues with this set up on a stock specs bottom end 5.3L?
Heads-
5.3L 706 castings, ported and polished, 5 angle valve job, 2.02/1.575 valves, Lunati .660 double springs, 1.75 roller rockers, 7.500 pushrods
Cam-
duration 219/224 lift 607/600 111 LSA

I will be spraying a 150 shot to it as well, if that makes a difference in the clearances at any point.

[WARLOCK]

I wouldnt think your would have any issues with that cam. Others will chime in.

[joeoby78]

I wouldnt think your would have any issues with that cam. Others will chime in.

Thanks for the feed back. I was concerned that the longer push rods, along with the increased roller rocker ratio may cause a problem. I thought I had everything figured right, but I'm starting to second guess myself. Just wanted to get some other peoples views on it before I put it in.

[WARLOCK]

Y are you running the longer pushrods? Jwing

[txarkitekt]

Does anybody think I may have any valve to piston clearance issues with this set up on a stock specs bottom end 5.3L?
Heads-
5.3L 706 castings, ported and polished, 5 angle valve job, 2.02/1.575 valves, Lunati .660 double springs, 1.75 roller rockers, 7.500 pushrods
Cam-
duration 219/224 lift 607/600 111 LSA

I will be spraying a 150 shot to it as well, if that makes a difference in the clearances at any point.

Did the new rockers require longer pushrods? Were the heads milled any? What base circle was the cam ground on?

(Thinking to myself) Worked heads have usually been decked or milled at least .010 and that would require a shorter pushrod...unless the new rockers have a different contact height for the pushrod...resulting in a slightly longer pushrod.

You *shouldn't* have PTV issues, but I would make sure to find out if using those rockers that stock 7.400 pushrods should be used.

[WARLOCK]

Thats why I asked why he was using "longer" pushrods.

[txarkitekt]

Thats why I asked why he was using "longer" pushrods.

Sure thing Gavin.

[joeoby78]

Y are you running the longer pushrods? Jwing

When I called to order the rockers, the guy had a package price for buying the push rods from him as well. I had a line on a set of used push rods, but thought what the hell I'll go ahead and get new ones it's a good deal. He rattled off the order and said 7.500 length and I asked him if that was right, he said that is what the rocker arms needed. I went with it and now I just want to make sure it's right.

[joeoby78]

Did the new rockers require longer pushrods? Were the heads milled any? What base circle was the cam ground on?

(Thinking to myself) Worked heads have usually been decked or milled at least .010 and that would require a shorter pushrod...unless the new rockers have a different contact height for the pushrod...resulting in a slightly longer pushrod.

You *shouldn't* have PTV issues, but I would make sure to find out if using those rockers that stock 7.400 pushrods should be used.

The guy I bought the rockers from said the 7.500 is what they needed, but I am just wanting to make sure he is telling me right. The cam is ground on a base circle a hair shorter than stock, is what the guy at Thunder racing told me. The heads are not being milled.

[RedHeartbeat]

what brand rockers? 7.4" is the stock length. 7.425" for an aftermarket cam with no head work. 7.5" may compress the lifters to the point you have a solid lift cam setup and could cause you to bleed off compression and burn valves if they don't close completely.