piston dome machining???

[oldsman71]

a guy close to here has a set of .500 dome pistons (.030 400 chevy)
is it ok to machine it to a flat top, what would it cost, and would
porosity be a problem? I havent ever had this done but have heard of this befor.
they are supposed to be solid dome. they are on resized, floated, rods
with new arp bolts, he wants $200 I want to
build a pump gas 406 thanks, cobey

[IRONHEAD]

Re: piston dome machining???

who made them..
a solid dome would make one heavy piston.

[BangShiftChad]

Re: piston dome machining???

I can't believe I'm agreeing with you, but that sounds funny.

You'll have to go look at them, but my first instinct would be no.

[Ron Ward]

Re: piston dome machining???

If you knock 0.500" off the top of a piston, you will remove a SERIOUS amout of material. I would shy away from the idea.


Ron

[oldsman71]

Re: piston dome machining???

who made them..
a solid dome would make one heavy piston.

TRW forged it didnt sound right to me but I thought
ID ask, I didnt get a part # from him

[oldsman71]

Re: piston dome machining???

I have to look this up but it was a TRW L2311 part # I think this is a no go
the guy sounds like he left them outside, got to love this stuff :P
he said blah blah blah blah.............................................. .................. Ill look for
some shallow dish trw or some sealed power flat tops
thanks for the help guys, I should have been smarter than that anyway :P :P :P :P :P :P :P :P :P :P

[jays67]

Re: piston dome machining???

I have to look this up but it was a TRW L2311 part # I think this is a no go
the guy sounds like he left them outside, got to love this stuff :P
he said blah blah blah blah.............................................. .................. Ill look for
some shallow dish trw or some sealed power flat tops
thanks for the help guys, I should have been smarter than that anyway :P :P :P :P :P :P :P :P :P :P

I have a set of 283 pistons that are domed and the domes have to be machined but that is how they are made and 500 would be a ton to cut off lol

I have a set of Eritle racing pistons new in the box I am not useing I will get you numbers ton=morrow when i go out in the shop

I would recomend on a 406 going to a 5.7 rod it wakes them up a whole bunch

[milner351]

Re: piston dome machining???

I machined a set of boss 302 arias pistons down from stupid high compression to maybe these will run on pump gas compression.

They started life with a relief machined into them for the spark plugs!

We removed enough material to drop the compression I think 3.5 points - it was NO where near .500!!!

We did it in a lathe taking several shallow cuts to keep the surface finish good.

[yellomalibu]

Re: piston dome machining???

What size chambers in your heads?

I'm going from memory here, but you can check on any number of online calculators... When I put together my first 406, I used flat top pistons, 5.7 rods (not that that matters to the c.r.) with AFR 195's with 68cc chambers. I believe the c.r. was approximately 11:1

With aluminum heads and a cam with enough overlap, 11:1 is fine with high octane pump gas. If you have steel heads with 64 cc chambers, I'd recommend using a D-dish piston to get the compression closer to 10:1.

^^^ That's assuming you are building a pump gas motor.

[JeffMcKC]

Re: piston dome machining???

What size chambers in your heads?

I'm going from memory here, but you can check on any number of online calculators... When I put together my first 406, I used flat top pistons, 5.7 rods (not that that matters to the c.r.) with AFR 195's with 68cc chambers. I believe the c.r. was approximately 11:1

With aluminum heads and a cam with enough overlap, 11:1 is fine with high octane pump gas. If you have steel heads with 64 cc chambers, I'd recommend using a D-dish piston to get the compression closer to 10:1.

^^^ That's assuming you are building a pump gas motor.

The lenght rod does make a difference in the What I call "Working comp" you can do on a Pump Gas engine. It will change the lenght of time the Piston is a TDC

[IRONHEAD]

Re: piston dome machining???

What size chambers in your heads?

I'm going from memory here, but you can check on any number of online calculators... When I put together my first 406, I used flat top pistons, 5.7 rods (not that that matters to the c.r.) with AFR 195's with 68cc chambers. I believe the c.r. was approximately 11:1

With aluminum heads and a cam with enough overlap, 11:1 is fine with high octane pump gas. If you have steel heads with 64 cc chambers, I'd recommend using a D-dish piston to get the compression closer to 10:1.

^^^ That's assuming you are building a pump gas motor.

The lenght rod does make a difference in the What I call "Working comp" you can do on a Pump Gas engine. It will change the lenght of time the Piston is a TDC

I'd think the stroke would have more affect on that than rod lenth..
as a longer stroke the tdc duration would be longer than a short stroke.. that hover at tdc/bdc less..

[oldsman71]

Re: piston dome machining???

What size chambers in your heads?

I'm going from memory here, but you can check on any number of online calculators... When I put together my first 406, I used flat top pistons, 5.7 rods (not that that matters to the c.r.) with AFR 195's with 68cc chambers. I believe the c.r. was approximately 11:1

With aluminum heads and a cam with enough overlap, 11:1 is fine with high octane pump gas. If you have steel heads with 64 cc chambers, I'd recommend using a D-dish piston to get the compression closer to 10:1.

^^^ That's assuming you are building a pump gas motor.

I got 76cc #441 GM or 64cc E brock performer want a mild pump gas motor for one of my cutlasses
I just want a bunch of low end power :D

[oldsman71]

Re: piston dome machining???

I have to look this up but it was a TRW L2311 part # I think this is a no go
the guy sounds like he left them outside, got to love this stuff :P
he said blah blah blah blah.............................................. .................. Ill look for
some shallow dish trw or some sealed power flat tops
thanks for the help guys, I should have been smarter than that anyway :P :P :P :P :P :P :P :P :P :P

I have a set of 283 pistons that are domed and the domes have to be machined but that is how they are made and 500 would be a ton to cut off lol

I have a set of Eritle racing pistons new in the box I am not useing I will get you numbers ton=morrow when i go out in the shop

I would recomend on a 406 going to a 5.7 rod it wakes them up a whole bunch

cool, I got a stock 400 crank and a set of 5.7 rods a guy about 60 miles away
has some KB flat tops, 6 used and a couple of new ones from a broken #8 rod im still
figuring what to offer, the pics look good and the guy knows his stuff, so I dont think he would
try to sell me crap!