When is fly cutting pistons necessary?
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 933
Likes: 0
From: St. Paul MN
When is fly cutting pistons necessary?
I'm doing a head/cam install this winter. I'm going with the Dart Pro 1 62cc heads with a GM head gasket. How big of a cam can I run before I have to worry about fly-cutting my pistons? I'm thinking about the comp cams XER281HR cam with the following specs:
Intake Duration: 232
Exhaust Duration: 234
Intake Lift: .595
Exhaust Lift .598
Lobe Separaton: 112
or possibly the XR281HR with the following specs:
Intake Duration: 228
Exhaust Duration: 230
Intake Lift: .571
Exhaust Lift .573
Lobe Separaton: 112
Am I pushing my luck with this size of a cam? I'm looking for big HP gains and I want somewhat of a racey idle but I don't want to have any valve/piston clearance problems or other valve train issues. Any input would be great!
In addition I'm looking at the z06 or FAST intake with headers.
Intake Duration: 232
Exhaust Duration: 234
Intake Lift: .595
Exhaust Lift .598
Lobe Separaton: 112
or possibly the XR281HR with the following specs:
Intake Duration: 228
Exhaust Duration: 230
Intake Lift: .571
Exhaust Lift .573
Lobe Separaton: 112
Am I pushing my luck with this size of a cam? I'm looking for big HP gains and I want somewhat of a racey idle but I don't want to have any valve/piston clearance problems or other valve train issues. Any input would be great!
In addition I'm looking at the z06 or FAST intake with headers.
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
I think you should be ok. As a rule of thumb, .080" on the intake and
.100 on the exhaust is the minimum. I have the G5x3 cam (238/242 .601 .610) with AFR 59cc, stock GM MLS headgaskets and I didnt flycut.
.100 on the exhaust is the minimum. I have the G5x3 cam (238/242 .601 .610) with AFR 59cc, stock GM MLS headgaskets and I didnt flycut.
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 933
Likes: 0
From: St. Paul MN
How does your car run with that size cam? Is it hard to keep in running when cold? Do you tend to fowl the plugs frequently?
Former Vendor
Joined: Apr 2007
Posts: 1,331
Likes: 4
From: Jacksonville Florida
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
What size gasket were you running?
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Intermediate
Joined: Nov 2007
Posts: 41
Likes: 0
Nailed on the head right there. I had the G5x3 in my 99 Z28 and had no problems whatsoever with drivability.
I'm going with Vengence Racing's Vindicator cam with my C5 and I'm sure it will be fine also. I have complete faith in my tuner.
I'm going with Vengence Racing's Vindicator cam with my C5 and I'm sure it will be fine also. I have complete faith in my tuner.
