Fly-Cutting Pistons....

[OutLawSE]

Guys,

My TFS Heads are milled .050. I would like to run the Crower 511 cam with 1.7s : .498/.515 Lift , 218/224 Duration.

Does anyone have any info on flycutting pistons? Is it easy to do and how do you go about cutting them.

The pistons are hyper.

Thanks....

 

[mike keirstead]

How do you know if you even need to? Have you check your P/V clearance?

 

[jls]

If the VAVE LIFTS with the 1.7 RR is truly .498/.515 Lift , and 218/224 Duration @ 0.050 then you should not need to flycut stock pistons. Or are those specs for a 1.6 rr setup or a 1.7 rr setup as stated?

Twisted Wedge websites says you can run up to 0.542 lift and 224 duration @ 0.050 without clearance problems with stock pistons.

ALWAYS check piston to valve clearance when you build a non-stock setup despite what I or anyone says.

IF you would ever need to flycut pistons for Twisted Wedge then it will be somewhat challenging as their valve angles are not stock valve angle so valve would hit the piston at different angle than what is cut into stock pistons. That's why some aftermarket pistons have special reliefs in them for the valve angle generated by Twisted Wedge Heads.

 

[Rick 91GT]

If you need to try www.totalengineairflow.com they use to rent a tool to flycut your pistons while in the block, I am sure they have one for TW.

 

[SilverBullit]

I've got the Crower 15511 cam with 1.7 rr and Edelbrock Performer heads and no problems (although they are 1.90/1.60 valves). Everyone has told me the lift on the Crower w/1.7's 500/518 no one has ever told me the numbers you posted although there's only a couple thousands of an inch.

Casey

 

[OutLawSE]

Guys....

Don't u think that since my heads have been milled .050 won't that cause a problem?

 

[OutLawSE]

Also,

How do you modify a old hydr roller lifter in your to measure your P/V clearance?
Do you just take out the spring and fill the lifter with a bolt or metal?

 

[Rick 91GT]

You can take the lifter apart and make it a solid or weld the lifter.

 

[mike keirstead]

You can also flip the float upside down. That works.

 

[bock]

Also,

How do you modify a old hydr roller lifter in your to measure your P/V clearance?
Do you just take out the spring and fill the lifter with a bolt or metal?

I just deprim(TAKE ALL THE OIL OUT IF IT) one of the lifter in a vise.... make it loose (i could compress it with my finger).