SPANKY LS1

iTrader: (24)

A buddy of mine picked up a set of used heads, and wants to verify how much they are milled so we can pick him out a cam. What is a good way to do this? I would assume that you could measure from the deck to one of the bolt surfaces, right? How close can we get, within .010 or so? Any other way to measure this? We're going to CC them, but the chambers have been ported on, so that won't tell us too much. Thanks, Shawn

Mike K.

measuring deck height is how I have always seen it done. You just have to compare it to a set of stock heads. Maybe someone has those measurements to give you ?

Richard@WCCH

iTrader: (3)

Measure the valve cover rail to the deck. It should measure 4.75" +or- .004" for a stock unmilled head. The most convienient place to measure with vernier calipers is at the ends of the head. Be sure that there aren't any nicks or burrs........

Good luck,

Richard

SPANKY LS1

iTrader: (24)

Forget to mention: They are 5.3 heads, is the above statement true for 5.3s also?

So, a stock head (5.3 too) should be 4.746"-4.754" right? Can anyone measure a stock unmilled 5.3 head to verify? I need it to be pretty exact. How close can we get with this method, within .005? Thanks, Shawn

Richard@WCCH

iTrader: (3)

I haven't got access to the factory blueprint for these heads, but the hundreds of them we've done over the years demonstrates the above info is correct for the 4.8l, 5.3l, 5.7l(&LS6) and 6.0l heads. I'm pretty sure the facory target size is 4.750" and the tolerance is + or - .003"-.004".

Richard

SPANKY LS1

iTrader: (24)

Thank you, Shawn

Old SStroker

How about just cc'ing the chambers? That's the information you need to calculate CR which is essential to know if you are attempting to pick a cam that works with your combination.

SPANKY LS1

iTrader: (24)

We are going to CC the chambers, but we are wanting to know how much they are milled so we can determine if a given cam will fit, and that info is unavailable.

98_1LE

iTrader: (17)

I think it is better to check p-to-v clearance rather than "calculate" or "guestimate" it, at least if it is going to be close enough to even think about.

SPANKY LS1

iTrader: (24)

Right, but he wants to know if it *should* fit before he plunks down $400+ for a cam.