TFS 215s PTV Clearance FWIW!!
07-15-2012, 12:22 PM
#22
TECH Senior Member
Well Pro stock usually runs Jesel keyway style lifters with pushrods like 1/2˝-9/16˝ diameter .200˝-wall thickness.
As I said, why argue, Grr obviously understands all that
As I said, why argue, Grr obviously understands all that
, best of luck, but one day you'll learn your lesson, that I guarantee.
lol
07-16-2012, 05:47 PM
#29
fyi Ive worked on probally 25 cam only ls1 cars, then taken the heads off all the intake valve had touched piston and it was running fine. pretty much any m6 car thats raced you will find like that. All with other common (name, PN) big cams they the shop says "is close but will clear stock heads" and if you check, no one ever really dose. P2V gets under .050, if you check most of the setups. Ive ran cam only setups under .025, its not really that spec that has a go/no go safe spec. The intake is chancing the piston as it moves down anyway. Min is @ about 10-15* ATDC, and not close to at max lift like most people think.
edit. ya if you guys want to get into it more, that mock up cam degree spec you get is not close to the real running motor. Check out the parts with some heat in them, stock part class stuff you need to account the block deck changing, the rocker pad height changes a bunch, valve length. And thats not even the deflections, Prod move alot, The rocker tip and fulcrum lash, The main, rod and pin clearances are going +++ to --- in the clearance range.... piston rock...big bad *** stuff the cam twist up a few * front to back.. see the that dose to you .0X PTV spec you use. (another benefit of 55,60mm)
edit. ya if you guys want to get into it more, that mock up cam degree spec you get is not close to the real running motor. Check out the parts with some heat in them, stock part class stuff you need to account the block deck changing, the rocker pad height changes a bunch, valve length. And thats not even the deflections, Prod move alot, The rocker tip and fulcrum lash, The main, rod and pin clearances are going +++ to --- in the clearance range.... piston rock...big bad *** stuff the cam twist up a few * front to back.. see the that dose to you .0X PTV spec you use. (another benefit of 55,60mm)
Last edited by studderin; 07-16-2012 at 05:59 PM.
08-21-2012, 11:07 AM
#32
Sorry to hijack thread OP but its dead anyway. I will be running about .060 PTV clearance in my setup coming up with nitrous. Camshaft it a 232/236 .625 112 lsa and ported milled 243's. Milled .015 using a .051 head gasket. Im going to run it and spin it to around 6300 rpm. Its a bit risky but I have seen guys run bigger cams than this (MS4) with heads that were milled and they ran for years. Im sure there are alot of other factors Im not taking into consideration such as valvesprings, pushrods size, etc. We'll see how mine works. Drives fine now but havent got it in the upper RPMs yet.
08-22-2012, 02:53 AM
#34
.035" is pretty tight... LG used to recommend the G5X3 (234/242 112+4) with 59cc AFR 205s with a .040" Cometic and no flycut. It had less clearance than that.
If a vendor is willing to warranty the work, then I don't know? Guess you could run it and hope the warranty holds. But there were plenty of packages of the G5X3/AFR205 sold, and I've never heard of them blowing up. I'm sure the valves kissed the pistons quite a bit, but it never failed. Same could be said of the T-Rex and MS4 cam only installs etc.
If a vendor is willing to warranty the work, then I don't know? Guess you could run it and hope the warranty holds. But there were plenty of packages of the G5X3/AFR205 sold, and I've never heard of them blowing up. I'm sure the valves kissed the pistons quite a bit, but it never failed. Same could be said of the T-Rex and MS4 cam only installs etc.
08-22-2012, 12:09 PM
#35
TECH Senior Member
Well there is such thing as pushing the envelope and there is just plain stupid and ignorant.
When was the last time you saw a shop paying for your motor because you kissed the pistons? Never.
Shops will do anything just to sell. You break, it is unfortunate but that still means more sales.
When did our ideology become "he has done it, so it should be ok". If so why don't we just become all killers since some people do that.
When was the last time you saw a shop paying for your motor because you kissed the pistons? Never.
Shops will do anything just to sell. You break, it is unfortunate but that still means more sales.
When did our ideology become "he has done it, so it should be ok". If so why don't we just become all killers since some people do that.
08-22-2012, 04:06 PM
#36
I'm not advocating - just pointing out that shops have been doing it for a while.
I should have said if you're lucky enough to get a warranty on the craftsmanship of the install/tune, you had better hope you never have to test out how well a shop is willing to stand behind that warranty.
I should have said if you're lucky enough to get a warranty on the craftsmanship of the install/tune, you had better hope you never have to test out how well a shop is willing to stand behind that warranty.
