04 6.0 build, piston to valve clearance
#1
Teching In
Thread Starter
iTrader: (4)
Join Date: Mar 2011
Location: Minnesota
Posts: 44
Likes: 0
Received 0 Likes
on
0 Posts
04 6.0 build, piston to valve clearance
Hi guys,
building an '04 LQ4 6liter. Got a few cams layin around and want to know what's the max lift before having any clearance issues.
Have used the .525/.532 with favorable results but would like to go bigger.
This motor is stock long block with a tune, headers, cold air intake etc.
Going in a 4,000lb, 72 truck with 700r4 and 410's with shorter than stock tires so the rear gear will technically be a set or two higher.
Any info from previous builds would be appreciated.
Trying to avoid pulling the heads and flycutting the pistons.
building an '04 LQ4 6liter. Got a few cams layin around and want to know what's the max lift before having any clearance issues.
Have used the .525/.532 with favorable results but would like to go bigger.
This motor is stock long block with a tune, headers, cold air intake etc.
Going in a 4,000lb, 72 truck with 700r4 and 410's with shorter than stock tires so the rear gear will technically be a set or two higher.
Any info from previous builds would be appreciated.
Trying to avoid pulling the heads and flycutting the pistons.
#4
10 Second Club
iTrader: (10)
Lift has no effect on PTV clearance. When the cam reaches max lift the piston is down in the bore. The valve events are what determines whether or not you will have clearance issues. The LQ4 has dished pistons which have more clearance than the flat top motors. You would have no problem going to a cam with 242/248 duration and as much lift as you want to run.
#7
Trending Topics
#9
Teching In
Thread Starter
iTrader: (4)
Join Date: Mar 2011
Location: Minnesota
Posts: 44
Likes: 0
Received 0 Likes
on
0 Posts
5.3 Jim,
I see you have a truck, Currently I have a 5.3 in a 3/4 ton truck with 410's and shorter than stock tires to get a even higher ratio. Also a 700r4. Stock cam with headers and a tune. The stock motor burns the tires through 3rd gear. (combo of power, high gear, and little weight in the rear) I would like to know what is the highest lift/duration I could use in this truck with the 5.3 , also putting a 6.0 in the same type of truck, would the cam be about the same for both motors. no stall
I see you have a truck, Currently I have a 5.3 in a 3/4 ton truck with 410's and shorter than stock tires to get a even higher ratio. Also a 700r4. Stock cam with headers and a tune. The stock motor burns the tires through 3rd gear. (combo of power, high gear, and little weight in the rear) I would like to know what is the highest lift/duration I could use in this truck with the 5.3 , also putting a 6.0 in the same type of truck, would the cam be about the same for both motors. no stall
Last edited by rdkonkel; 11-02-2011 at 11:33 AM. Reason: added name of poster
#10
10 Second Club
iTrader: (10)
The raised edge will cause a clearance issue with the side of the valve but at the tip of the valve(closest to the intake) the dish has more clearance. I'm not saying that the dish has as much clearance as a flycut piston but it does offer a bit more. If you look at a picture of a piston in a car that has had some PTV contact you can see the "eyebrow" is far from the raised edge of a dished piston.
#12
The raised edge will cause a clearance issue with the side of the valve but at the tip of the valve(closest to the intake) the dish has more clearance. I'm not saying that the dish has as much clearance as a flycut piston but it does offer a bit more. If you look at a picture of a piston in a car that has had some PTV contact you can see the "eyebrow" is far from the raised edge of a dished piston.
Side question, is that 5.3 jimmy setup you have AWD?
I'd say you would be plenty safe.
Last edited by 93Z2871805; 11-03-2011 at 01:00 AM.