Mark O'Neal wrote: ↑Tue Sep 25, 2018 1:34 amI don't mind you asking at all, and I wouldn't mind answering, but skirt design is a frightfully complicated subject. It used to be a world of cam and taper, and now it's a world of shapes. Even the thickness of the skirt comes into play. The change in skirt designs is like when we went from black and white to color tv. Bonanza entered a completely different universe.Casper393W wrote: ↑Mon Sep 24, 2018 4:05 pmMark O'Neal wrote: ↑Sun Sep 23, 2018 6:26 pm What Walter said.
Tell Randy what you're doing and give him your finish bore size. Have him put the clearance in the piston. Takasawas get the finished sizes within about .0001. It's not an issue.
4032 is priced and marketed as a "lower quality" composition. It is not. Nor are they less expensive to make. Actually they are more expensive to make. That nonsense is all marketing. Nor can you run them any tighter, really. You can run 2618 at .0025 (4.030 bore) if they cut the skirts properly.
My own opinion is that pretty much anything that will destroy a 2618 piston will kill a 4032...given an equal layout....and I've seen racers turn both alloys into BBs.....bless their hearts.
Thanks for posting this.... I have always been told to run a 2618 looser in the bore compared to 4032... If you don't mind me asking what would be the difference in the skirts to run the 2618 tighter? I have seen many 4032 pistons scuffed in 03,04 Cobras due to "in my opinion" cylinder thickness in cylinders 7 and 8 and the coolant flow causing higher heat buildup in those cylinder.
I am a fan of the 4032 Mahle pistons... I have seen serious power made on those pistons.. 1000+ I told them if you ever rattle them kiss them goodnight! But it never happened
The skirt I used came from the Ford Technology transfer program. We ran 2618 as tight as .0025. Scuffing was never an issue.
I'm not a Mahle fan. The pistons are fine, I'm just weary of the major corporations driving out the smaller manufacturers and engine builders that built the hobby, so I try to deal with the mom and pop operations and steer clear of the behemoths.
Thank you sir, I need to rephrase what I was saying about the Mahle pistons... I like the design... Like you said companies such as Mahle do make it extremely hard for the small business owner... I know I have brought this up on another thread and I took a beating over it... When I am sourcing parts for engine builds I always try my very best to buy from American companies and to break it down even more I have a few vendors that I buy from that are "Mom and Pop" shops... They provide me a quality product not always the cheapest but I know at the end of the day they will make things good if I run into problems.....
Andy