Picture of a cut piston

[LBZ]

I need a picture of a de-lipped stock piston for a machinist buddy of mine. Can someone throw a couple up for me asap?

Thanks

 

[JoshH]

I think Trent posted pics of his pistons in his build thread.

 

[LBZ]

yup got it thanks Josh

 

[RPM Motorsports]

..

 

[LBZ]

Sweet!!! My buddy can do it. Gonna send him a couple used slugs to practice on.
My cheap ass is savin money on this build somewhere finally!!

 

[paint94979]

Sweet!!! My buddy can do it. Gonna send him a couple used slugs to practice on.
My cheap ass is savin money on this build somewhere finally!!

Dale you know you want those forged pistons in Russ's picture you cheap Canuck:hug:

 

[LBZ]

Nope

 

[paint94979]

Nope

lies :joker:

 

[LBZ]

not even a little bit

 

[TrentNell]

Sweet!!! My buddy can do it. Gonna send him a couple used slugs to practice on.
My cheap ass is savin money on this build somewhere finally!!

Sweet Dale always good to save money where you can , he shouldn't have any problems doing it , it was my first time and after 1 practice piston it wasn't too bad hardest part was making them all the same . There are plenty of schools of though on what is right or wrong way to do it , just go with your best judgment and talk with a few different people, the way I cut mine may not be worth a darn, I wont know until i run it for a bit but at least if they break i can go to the mirror and yell at the sum bitch who cut em and designed em :rofl: :rofl:.

 

[LBZ]

Well lets hope you don't have to go to the mirror!!

Is there any sort of specs on what to cut to?
If I just de-lip a stock lly, what sort of compression would I end up with?

 

[LBZ]

Well this just went tech so may as well put it here!

 

[TrentNell]

Well lets hope you don't have to go to the mirror!!

Is there any sort of specs on what to cut to?
If I just de-lip a stock lly, what sort of compression would I end up with?

Just some info , i opened mine up to 2.60 dia took zwero off the top and the best i can figure mine ended up around 15.2-15.0 , If you dont want to cut compression just take it out only far enough to get rid of the lip and do a radius , are you cutting valve reliefs for bigger cam ? if not then from what i have heard just taking the lip off will drop you to around 16.5-16.9 or so ? If in doubt do a before and after "cc" test . I did on mine and it ended up pretty close Josh H , and Johnboy were a big help to me on the "math" .

 

[TrentNell]

Heres another picture of mine for easier reference . I should note that my Radius is considered "large" compared to what most do .

 

[S Phinney]

Yes Trent, you do have it opened up a little there. Did you coat them also?

 

[TrentNell]

Yes Trent, you do have it opened up a little there. Did you coat them also?

No

 

[LBZ]

Thanks Trent I'll keep it in mind. I'm gonna send a couple to my mate there on Vancouver Island for him to play with and when we get something I like, we'll just copy it. Like you say, hard part will be getting them all the same but he runs CNC stuff so he can probably program it somehow to follow the same dimensions or something.

I dunno-that craps all magic to me......

 

[Dallas S]

What is the biggest concern when cutting pistons "the same"? is it a matter of getting all 8 pistons the same shape, or getting them the "same" weight? what is a general tollerance on weight,(2 grams, 5 grams ect)?

To me it seems that weight would be more so a concern. it would be better to make the bowl a bit bigger on one to get the same weight as the others... thats just my un-educated thought.

 

[JoshH]

When you cut the piston you need to make sure the compression height and the bowl volume to be the same on all the pistons. When the motor is balanced, the pistons will all be made the same weight.