I know these have been beaten to death with questions but i just wanna make sure i got this right. I've built plenty of pushrod 5.0's but got 187,000 miles on my 4.6 and am startin to prepare for a rebuild. I picked up a set of patriot stage II heads and a set of comp cams 270. I'm gonna run the sock pistons and am worried about ptv clearance. i am gonna do the clay test regardless but am getting the perception that as long as i degree the cams properly i should be good. Is this true even with the bigger valves of the heads?
comp cams 270
- Thread starter stangjay
- Start date
lvmustanggt
New Member
you must degree the cams properly. one of the fastest bolt on cars in country on my list(automaticweapon at 12.02 I believe) blew his motor with them. Ive read tons of threads with people with no problems, and many people with them even though they degreed the cams.
I actually sat down with my engine builder a few weeks ago at westside machine in houston. He has had 2 cars blown from 270-278's with the cams degreed. 6 that are fine as of the time. He suggested cutting the pistons, though Ive been told time and time again it does not need it if degreed properly.
Ive been messaged from some of the fastest NA mod guys in the country, and they all say, do not use comp springs! Go with crower or others if you plan on track use and winding the car out.
Im not discounting lvmustanggt, but I have personally been on the losing end of a trashed 2v motor and ruined valvtrain from cams, and I am hesitant about the 270's with as many problems.
I actually sat down with my engine builder a few weeks ago at westside machine in houston. He has had 2 cars blown from 270-278's with the cams degreed. 6 that are fine as of the time. He suggested cutting the pistons, though Ive been told time and time again it does not need it if degreed properly.
Ive been messaged from some of the fastest NA mod guys in the country, and they all say, do not use comp springs! Go with crower or others if you plan on track use and winding the car out.
Im not discounting lvmustanggt, but I have personally been on the losing end of a trashed 2v motor and ruined valvtrain from cams, and I am hesitant about the 270's with as many problems.
i have the 270's and had trouble with ptv. if u install them on a a 109 intake centerline ur intake valves will hit the pistons. i had to retard mine quite a bit to get the clearance that was needed. if ur heads have bigger valves i would highly recommend u flycut the pistons. if im not mistaken though the patriot stage 2's dont have bigger valves and the stage 3's do. i could be wrong about that. either way if i were u i would fly cut the pistons to be on the safe side.
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