Jiver67

Hi all,

This is my first post here on LS1Tech. I normally hang out on the Corvette forum but have found that you folks tend to be more technically saavy with regards to modifying and racing the LS1/LS6 engines.

Anyway, my question is the following:

Which is the better valve spring to use with the LPE GT2-3 cam (.571"/.573", 207/220, 118.5), the '02-'04 LS6 spring or the Comp Cams 26918 piece? I have decided to stay with a single spring design as I feel that a double spring would be overkill for this camshaft.

Also, does anyone know the seat and open load specs for the factory LS6 spring?

Thanks in advance,

Jiver67

Full-Force

iTrader: (11)

summit prices are gonna be about 112 for ls6 springs and 159 for 918's

918's are good to .600 compared to .570 for the ls6

money well spent on the 918's even if you have to wait another couple weeks to save up 50 more bucks

whatever you buy, i would get them from a sponsor to the right ( i just used summit as price comparo cuz i have a book at my computer)

jrp

iTrader: (16)

90#'s @ 1.800
294# @ 1.320

if i recall, for the 02+ ls6 springs. you can check the 918 specs in the cam guide (sig or sticky). personally i'd run the 918 and tit. retainer.

Jiver67

Thanks guys...looks like the Comp springs are the way to go. As for Comp Cams titanium vs. steel retainers for this spring, are the titanium pieces in fact lighter? I have heard that titanium retainers can often be heavier than steel (guess it really depends on brand, i.e. Comp vs. Crane).

jrp

iTrader: (16)

http://www.krcperformance.net/newcontent/beehive.html

Jiver67

Jerami,

Thank you...that was a very informative article!

So, it looks like the trick setup is:

Comp Cams 26918 Beehive springs
Comp Cams 772-16 Titanium retainers

What is your take on Ferrea hollow-stem stainless steel valves? Cost?

I know the '02-'04 LS6 is equipped with hollow-stem intake valves and sodium filled exhaust valves from the factory. Apparently the LS6 valves are much lighter than the standard LS1 valves because of this (and the exhaust valves run much cooler due to the sodium-potassium material).

Don't think I want to know what titanium valves would cost!

jrp

iTrader: (16)

IMO the hollow stems arent needed in your situation, which i assume is just daily driving with the occassional run at the strip.

FWIW im going with hollow stems in my applilcation (roadracing) as i'll be seeing extended high rpms with a peak of ~7500 and want to keep my recipricating mass down. i looked into tit. valvee, and yes you are right, big money.

Redneck Z

iTrader: (3)

You might be better with the 918's, I'm not sure. I believe though lingenfelter recommends the LS6 springs. I heard the LS6 springs used to be rated for .600 lift, but now they use .570 so you'd probably be fine. Don't let price sway you, but the LS6 springs are $52 from SDPC.

Jiver67

Yes, basically you are correct on the application....spirited street car with ocassional visits to the track. I would really like the motor to pull to 6600 RPM reliably without having to change springs every 20,000 miles. If this can be done with factory Z06 springs, steel retainers and aftermarket stainless valves (not hollow-stem) so much the better....but I'm thinking the valve train would need to be lightened a bit to achieve this. How about titanium retainers used with the factory Z06 springs and stainless valves? The titanium retainers should save quite a bit of weight over the steel retainers and makeup for not using the lighter hollow-stem valves.

Good point on the Comp 26915 springs...these may be more than ample for the GT2-3 cam with the added benefit of less seat & open pressure than the 918s.

All good points here!

vettenuts

iTrader: (4)

Personally, I would also consider the Crane dual valve springs. The seat pressure is 112# which is between the two you are considering. Worth a peak anyhow IMO.