bigeller

iTrader: (2)

I have a set of brand new bare SDPC CNC LS6 heads.. They are unmilled as of right now with 70cc chambers. They will be perfect for my Escalade engine which has the 71cc stock D port truck heads. The cheapest way to get these heads up and running is to have the heads cleand and the stock valves lapped in.. The heads already have a top notch race valve job for the stock vlave sizes.. Here is my question: How much power and torque would I stand to gain if I were to run 2.02" and 1.60" valves instead of stock in the 6.0 H.O.? I just wanted to see if it would be worth the extra $$$ of buying bigger valve and having the seats recut.. I personally think I should have them cleaned, lapped, and get the heads on.. Please let me know your thoughts. These heads are purdy

Thanks
Eller

10secondZ

iTrader: (24)

You would gain a few ponies installing 2.02's and 1.575's in those seat's....but with the extra valve job the bowls would have to be re-worked (ported) due to the new seat cut's...I would say use stock 2.00's/1.55's and add a back cut or 2 to the stock valves...I would mill those head's .010 just for a clean up and straight surface..but other than that..just work with the stock valves unless you can port fairly well...Later,

Carter

Nasty N8

iTrader: (33)

I would think you could see plenty more power from bigger valves. But I am not sure if there CNC porting will compliment the valves I am sure the porting is done to maximize the stock valves. You could have the bigger valves put in and have the pockets ported.
Nate

robertbartsch

SDPC claims bigger valves on an LS6 head do not produce significant gains...

Ragtop 99

iTrader: (7)

gains going to a 2.02/1.57 aren't huge, but are there when properly ported to match. If I were starting from scratch that is what I would use. Given what you bought has performed well as ported, I would stick stock valves in and be done with it.

J-Rod

The heads were optimized for the stock valves. Going to a bigger valve has actually caused the heads to loose flow. SDPC posted this in the thread on these heads. Stock vlaves are the way to go. Perhaps a Ferrera valve in the stock size since they tend to pick up some flow over the stockers.

robertbartsch

...why did you buy bare LS6 heads compared to the ported finshed heads...?

..Isn't it more expensive to take a bare head and install LS6 valves and springs Vs. buying an assembled head.?

megathumpzillaX

Are you %100 sure they wern't milled? I thought that was the standard cnc thing. If you ordered them unmilled never mind. Just cautious

Pro Stock John

iTrader: (34)

LS6 heads are 64cc's stock.

bigeller

iTrader: (2)

Here is the link to my heads: http://www.sdpc2000.com/cart.asp?act...&pid=90938