![SEARCH](http://www.mustangworks.com/images/search.png)
![The Mustang Works](http://www.mustangworks.com/images/mw_footer_logo.gif)
© Copyright 1995 thru 2008 - The Mustang Works™. All Rights Reserved.
MustangWorks.com is designed and hosted by Aero3 Media.
MustangWorks.com is designed and hosted by Aero3 Media.
![]() |
#1 |
Registered Member
Join Date: Jul 2000
Location: Norman, Oklahoma, USA
Posts: 597
|
![]() Does anyone know how deep valve reliefs can be cut into late 70's flat top 302 pistons? Just how thick do you think the tops of the pistons are? Thanks.
__________________
Michael Black QuantumMotorsports Norman, OK 1984 LX Hatch 306 w/ TRW forged flat toppers, Comp Cams Magnum 292H, GT40P heads w/ 3 angle valve job, .550 lift springs, Angus Racing Roller Rockers, Weiand Stealth Intake, Holley 4150 650cfm carb, MAC 1 5/8 Long Tubes, Single Chamber Flowmasters, 91' T5 w/ Pro 5.0 shifter, Turbo Coupe 8.8 Rear w/ 3.55 gears, QA1 Motorsports tubular K member, no interior except steering wheel and seat. Coming soon: 6 or 8 point cage, Fuel Cell, Weld Draglites |
![]() |
![]() |
![]() |
#2 |
Moderator
Join Date: Mar 2001
Location: Myrtle Beach SC
Posts: 1,643
|
![]() Some of the different cam companies make a kit to do such a thing., Installs in place of a valve, then you install the head, put the end of the tool in a drill and start cuttin.. Other than that I dont know what is involved. I know that you need .100 thickness on the top of the piston to be able to cut reliefs.
Bradley
__________________
1990 GT, 347, TFS TW Heads, TFS Cam, TFS Track heat, Twin turbos, FMIC, T5. Built Ford Tough Moderator |
![]() |
![]() |
![]() |
#3 |
Registered Member
Join Date: Oct 1998
Location: Az
Posts: 854
|
![]() how big of a cam are you trying to make clearance for?
__________________
84 convt,roller 302,AFR's, performer 3.55's, underdrives BBK shorties stock cam, 1.7's 13.58@102.84 and a '68 stang .. project 8 sec street car... 557 big block + N20 :-) http://members.cox.net/darkknight302/68nwrear.jpg |
![]() |
![]() |
![]() |
#4 |
Registered Member
Join Date: Jul 2000
Location: Norman, Oklahoma, USA
Posts: 597
|
![]() Comp cams 292H (.534 lift, 244 duration at .050 lift)
Flat tappet hydraulic if it makes any difference. Thanks.
__________________
Michael Black QuantumMotorsports Norman, OK 1984 LX Hatch 306 w/ TRW forged flat toppers, Comp Cams Magnum 292H, GT40P heads w/ 3 angle valve job, .550 lift springs, Angus Racing Roller Rockers, Weiand Stealth Intake, Holley 4150 650cfm carb, MAC 1 5/8 Long Tubes, Single Chamber Flowmasters, 91' T5 w/ Pro 5.0 shifter, Turbo Coupe 8.8 Rear w/ 3.55 gears, QA1 Motorsports tubular K member, no interior except steering wheel and seat. Coming soon: 6 or 8 point cage, Fuel Cell, Weld Draglites |
![]() |
![]() |
![]() |
#5 |
Registered Member
Join Date: Oct 1998
Location: Az
Posts: 854
|
![]() have you clayed them to see how close they are, you shouldnt have probs going deeper if you need too.. I cut a set of TRW flat tops .090 deeper to clear a .640 lift cam.. so you shouldnt have to cut much.. if any...
__________________
84 convt,roller 302,AFR's, performer 3.55's, underdrives BBK shorties stock cam, 1.7's 13.58@102.84 and a '68 stang .. project 8 sec street car... 557 big block + N20 :-) http://members.cox.net/darkknight302/68nwrear.jpg |
![]() |
![]() |
![]() |
#6 |
Sniffed too much n20
Join Date: Oct 1998
Location: Ont, Canada
Posts: 1,018
|
![]() I know they're not early pistons, but I cut my reliefs in my 87-92 pistons with a dremel. Not hard to do, but go slowly. I had to clear for a TFS Stage 2. (.542/.563)
__________________
2002 Windsor Weekend Q16 Qualifier |
![]() |
![]() |
![]() |
#7 |
Registered Member
Join Date: Jul 2000
Location: Norman, Oklahoma, USA
Posts: 597
|
![]() Cool, thanks guys. I figured you should be able to cut about .050 - .090 or so but wasn't sure. I've got a couple griding wheels that are right at 2" diameter so they should work good to cut out for a valve. Thanks again.
__________________
Michael Black QuantumMotorsports Norman, OK 1984 LX Hatch 306 w/ TRW forged flat toppers, Comp Cams Magnum 292H, GT40P heads w/ 3 angle valve job, .550 lift springs, Angus Racing Roller Rockers, Weiand Stealth Intake, Holley 4150 650cfm carb, MAC 1 5/8 Long Tubes, Single Chamber Flowmasters, 91' T5 w/ Pro 5.0 shifter, Turbo Coupe 8.8 Rear w/ 3.55 gears, QA1 Motorsports tubular K member, no interior except steering wheel and seat. Coming soon: 6 or 8 point cage, Fuel Cell, Weld Draglites |
![]() |
![]() |
![]() |
#8 |
Registered Member
Join Date: Oct 1998
Location: Az
Posts: 854
|
![]() I'd clay them 1st... you shouldnt need to cut that much...
__________________
84 convt,roller 302,AFR's, performer 3.55's, underdrives BBK shorties stock cam, 1.7's 13.58@102.84 and a '68 stang .. project 8 sec street car... 557 big block + N20 :-) http://members.cox.net/darkknight302/68nwrear.jpg |
![]() |
![]() |
![]() |
#9 |
Registered Member
Join Date: Jul 2000
Location: Norman, Oklahoma, USA
Posts: 597
|
![]() Oh, i forgot, the heads are GT-40P heads which have slightly larger valves. I guess I'll just clay them and see. Or maybe I'll go ahead and put a .070 cut in them or so. Does anyone know how deep the stock HO pistons are cut? And what size of cam they can handle? Thanks.
__________________
Michael Black QuantumMotorsports Norman, OK 1984 LX Hatch 306 w/ TRW forged flat toppers, Comp Cams Magnum 292H, GT40P heads w/ 3 angle valve job, .550 lift springs, Angus Racing Roller Rockers, Weiand Stealth Intake, Holley 4150 650cfm carb, MAC 1 5/8 Long Tubes, Single Chamber Flowmasters, 91' T5 w/ Pro 5.0 shifter, Turbo Coupe 8.8 Rear w/ 3.55 gears, QA1 Motorsports tubular K member, no interior except steering wheel and seat. Coming soon: 6 or 8 point cage, Fuel Cell, Weld Draglites |
![]() |
![]() |
![]() |
#10 |
Registered Member
Join Date: Oct 1998
Location: Az
Posts: 854
|
![]() it's not so much the lift as it is the duration that causes the problem.. the piston starts to get close to the valve on the way up.. so the longer you hold it open, the more chance of hitting..
clay it and see.. here's a link for you http://66.96.130.106/archives/1999/10/ptov/index.shtml
__________________
84 convt,roller 302,AFR's, performer 3.55's, underdrives BBK shorties stock cam, 1.7's 13.58@102.84 and a '68 stang .. project 8 sec street car... 557 big block + N20 :-) http://members.cox.net/darkknight302/68nwrear.jpg |
![]() |
![]() |
![]() |
#11 |
Registered Member
Join Date: Jul 2000
Location: Norman, Oklahoma, USA
Posts: 597
|
![]() When you use the clay to check clearance do the lifters not compress since there is no oil pressure? I guess I could remove two valve springs. Anyway. Thanks for the help guys.
__________________
Michael Black QuantumMotorsports Norman, OK 1984 LX Hatch 306 w/ TRW forged flat toppers, Comp Cams Magnum 292H, GT40P heads w/ 3 angle valve job, .550 lift springs, Angus Racing Roller Rockers, Weiand Stealth Intake, Holley 4150 650cfm carb, MAC 1 5/8 Long Tubes, Single Chamber Flowmasters, 91' T5 w/ Pro 5.0 shifter, Turbo Coupe 8.8 Rear w/ 3.55 gears, QA1 Motorsports tubular K member, no interior except steering wheel and seat. Coming soon: 6 or 8 point cage, Fuel Cell, Weld Draglites |
![]() |
![]() |
![]() |
#12 |
Import Slayer
Join Date: May 1999
Posts: 2,241
|
![]() quantum , it funny that you posted this thread because I just bought the same exact cam for my 351w I'm building. I'm a little bit worried about clearance too. The valve relieves in my new pistons seem pretty deep(not sure exactly).
I was thinking about getting them flycut before I put it together and not have to worry about getting it together and finding out that I need to tear it apart to get the pistons cut. Competition Cams recommends that you use a solid lifter when checking piston/valve with a hydraulic cam because hydraulic lifters bleed down and give a false reading.
__________________
'82 GT 351W (.060)Comp Cams 274* Extreme Energy cam, ported & polished heads w/ 1.94/1.60 valves 10.3:1 flat top pistons,stealth intake, Mallory dizzy,Holley 750dp carb, BBK shorties,Flowmaster exhaust,C-4 with 3700 stall converter, B&M pro shifter,8.8 rear, 4:10's, subframes, electric fan, powermaster alternator, 4 core radiator. |
![]() |
![]() |
![]() |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
valve problem | pearlgt40 306 | Windsor Power | 3 | 07-05-2003 01:21 AM |
Largest cam in 351W without cutting the pistons (Looking at AFR185s) | Fox Body | Windsor Power | 10 | 06-15-2003 12:39 AM |
Pistons for Larger Valves? | MustangChile | Classic Mustangs | 4 | 02-28-2003 01:27 AM |
PCV Valve what the ?@#$@#$@$ | Chevyguy | Windsor Power | 3 | 04-11-2001 08:01 PM |
fly cutting pistons? | gpinto2 | Windsor Power | 1 | 01-02-2001 12:11 AM |