To flycut or NOT to flycut
To flycut or NOT to flycut Alright guys i measured my PtoV clearance the other day(dart 225, .040 cometic, cam in sig) and i came up with plenty on the exhaust (.100) but i was pretty close on the intake (.063).
From what I read from tony mamo wrote in one of the threads while back was minum clearance using a checker spring was .065 intake and .08 exhaust. Now i'm right on the border for the intake, my question is am I ok, or should i flycut it for added security.
Thanks
Justin
From what I read from tony mamo wrote in one of the threads while back was minum clearance using a checker spring was .065 intake and .08 exhaust. Now i'm right on the border for the intake, my question is am I ok, or should i flycut it for added security.
Thanks
Justin
Originally Posted by fotoboy
go with a thicker head gasket? loose a little comp but safer than flycuting
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From: Cecil County Raceway!!!
Originally Posted by GuitsBoy
Id flycut. You may want to go bigger on the cam one day (larger duration, anyway).
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Verdad Gallardo Joined: Nov 2001
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From: Cecil County Raceway!!!
Originally Posted by PREDATOR-Z
I'm not a big fan of flycutting for integrity and balance reason.
IMO run a thicker gasket, .045
IMO run a thicker gasket, .045
I'm not sure this is something I'd want to try in the driveway.
http://www.forcefedhighperformance.com/tech_Isky.htm
Did any of you guys do your own fly cutting?
http://www.forcefedhighperformance.com/tech_Isky.htm
Did any of you guys do your own fly cutting?
TECH Senior Member
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From: Western Burbs of Detroit
My pistons were flycut about 4000 miles ago, and no problem to date. Make sure you set the cutting tool correctly, check and double check the depth you are cutting. Sean at
Lg Motorsports did a good job on my toy.
Lg Motorsports did a good job on my toy.
I flycut... Myself.... In my driveway.... With a home made tool... Running perfect for 5K+ miles.
Dont cut deep and IMO you wont have any balance or durability issues.
Dont cut deep and IMO you wont have any balance or durability issues.
TECH Senior Member
Joined: Mar 2004
Posts: 14,620
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From: BFE
Originally Posted by Fireball
I've had .100 cuts for years and routinely spin over 7000 rpm....I'm not worried about the integrity or balance issues.
Like said (in general), there are some tuff blocks out there but most do not last long on these radical setups, without conrod bolt swap, 100% valvetrain geometry blueprint etc....
We don't call you nutcase for nothing Fireball
Joined: Nov 2001
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From: Cecil County Raceway!!!
Originally Posted by PREDATOR-Z
Oh yeah, many practice it, but not my cup of tea. In general if you need to flycut on a stock block, you are overcammed for the shortblock strength.
Like said (in general), there are some tuff blocks out there but most do not last long on these radical setups, without conrod bolt swap, 100% valvetrain geometry blueprint etc....
We don't call you nutcase for nothing Fireball
Like said (in general), there are some tuff blocks out there but most do not last long on these radical setups, without conrod bolt swap, 100% valvetrain geometry blueprint etc....
We don't call you nutcase for nothing Fireball
several years ago I had to flycut for a 232/232 112 cam with 5.3L heads milled .040. That is not overcammed by any stretch of the imagination
Yea I dont think i'm overcamming at all, but anyways i dont think a .045 gasket would make much of a difference. That would make my clearance around .068 on the intake, not much of a difference from what i have now.
I can see where you would think it would mess up the balance but I would be grinding out such a small amount of weight out of each piston, i would think the carbon build up on top of my piston would weigh more then how much metal i'm cutting out.
But anyways its your opinon Predator-Z and you always bring up good points. I think i'll just cut the intake about .040, now need to find someone, or someplace that will rent the tool out for me.
Unless you guys think i'll be fine and just run it how it is.
Thanks a lot for the opinions
I can see where you would think it would mess up the balance but I would be grinding out such a small amount of weight out of each piston, i would think the carbon build up on top of my piston would weigh more then how much metal i'm cutting out.
But anyways its your opinon Predator-Z and you always bring up good points. I think i'll just cut the intake about .040, now need to find someone, or someplace that will rent the tool out for me.
Unless you guys think i'll be fine and just run it how it is.
Thanks a lot for the opinions
TECH Enthusiast
Joined: Jan 2004
Posts: 539
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From: Grand Rapids, MI
I flycut mine, but I actually had interference on the intake (@ -.008). It's a not that difficult just takes a lot of time to do it right. I don't think I'd flycut with .063 on the intake, you have to remember the piston is chasing the exhaust valve, not the intake, so if you have any kind of valve float it will get you on the exhaust valve, not the intake. Now if you mechanically over-rev I don't know if you can have enough clearance 
Well i talked to Tony Mamo from AFR (real nice guy) came to the conclustion that i should fly cut, said with the lsk lobes theres a good chance to float them on a miss shift and i would prolly kiss the valve when i did.
Now just need to figure out what size cutter, the vlave i'm running is a 2.05 so thinking either a 2 1/8 or 2 1/4
Now just need to figure out what size cutter, the vlave i'm running is a 2.05 so thinking either a 2 1/8 or 2 1/4
Well i couldnt find a tool to rent out so i just ordered it form isky since they are just 30 min from me. Got a dummy head, and found a place that will cut the seat out for me.
So if anyone needs a flycutting tool i'll rent it out to ya pretty cheap
So if anyone needs a flycutting tool i'll rent it out to ya pretty cheap