lift ongt40p heads?
03-15-2007, 03:01 PM
#4
Thread Starter
Join Date: Mar 2007
Posts: 10
RE: lift ongt40p heads?
thats what i was told about the stock heads but i still put.511 on those and it worked fine with stock springs. I was thonking if i changed out the springs to a stronger double spring oit would work. Any ideas?
03-15-2007, 03:12 PM
#5
6th Gear Member
Join Date: Dec 2006
Location: Citrus County, FL
Posts: 8,007
RE: lift ongt40p heads?
supposed to be .500, i wouldnt personally go over .475 but w/e its your call. your gonna end up with coil bind and destroy your motor. <~ 5 years as a head shop machinist talking right there
03-15-2007, 03:21 PM
#6
Thread Starter
Join Date: Mar 2007
Posts: 10
RE: lift ongt40p heads?
Ok so my question is how do i get more lift out of the heads? Different springs, slightly longer valves, move up to 1.7 rockers, there has to be a way. With my cam now i have no bind issues or PTV clearance problems witha little over .500 of lift
03-15-2007, 03:31 PM
#7
6th Gear Member
Join Date: Dec 2003
Location: cape giradeau,mo
Posts: 8,872
RE: lift ongt40p heads?
with the right springs you can get over .500..but not over .550 with pedestal style rockers...now get them studded with 7/16's with the right springs you can get some lift...as long as your ptv is good....
03-15-2007, 03:38 PM
#9
5th Gear Member
Join Date: Jan 2006
Location: Puerto Rico
Posts: 3,926
RE: lift ongt40p heads?
If you have the stock springs....the exhaust side will bind @.510" lift.......you have to leave a .060" gap between the coil bind height of the springs and the actual lift on the valve....+ you need the spring rate requirements to support the cam lobe profiles and prevent valve float......upgrade them, it's long overdue....my 2ยข.
