I am about to build up a engine & I am very interested in using the mahle piston.

Has anyone had good or bad experience with the mahle piston in a evo application, if so, please share your experience.

TIA

 

I would like to know as well. Apparently these keep good tolerances for a forged piston(doesn't expand as much) and makes for a quiet, oil burning free forged motor(relatively speaking). I know the suby boys love them as well.

 

I recently built an engine with these. They are the highest quality pistons I have seen. Set piston to wall at .004 as I was planning to run 93/meth at 25psi+. Ring seal was amazing right from the start. These pistons are stronger than stock pistons but not as strong as 2618 forgings.. The alloy is the 4032 which is weaker than 2618. I picked them because I wanted a queit engine that would last near as long as stock pistons. I would say they are a fine choice for 500whp and less. Over that I would recommend the stronger forgings.

 

Im running them with my setup. Ill be sure to report a lengthy review when i get her started and broken in here in about 2 weeks

 

^ what are your power expectations?

 

I have there rods.

 

I would say that is about right. I noticed on the AMS 23RR Engine that the piston weight is at about 260 grams which is inline with the weight of the Mahle pistons. Although, I have no proof of the pistons in use there, I'll go out on a limb and say they are indeed Mahle pistons. That being said, AMSs' initial Dyno #'s were at about 450 hp. More importantly, one can eliminate other weight, i.e. rod weight and crank weight. Rod weight only if one were to not exceed the 500 hp mark because the integrity of a rod comes into play, although one might counter that by saying that since the pistons are less weight, the rod could support a higher piston speed, and therefore more hp. Crank weight would also be lessened as the assembly would have to be balanced, so the counter weight would be less too. I suppose you could support more hp with those pistons if you used different rods, say Carillo Rods. You could push a lot more, but you'd need to change your pistons more ofter than you would want to. I'd guess as long as the environment that the pistons survive is conducive to the pistons integrity you would be fine, i.e lower EGT temps. Also, at the point at which you move to a heavier rod, you will lose the response one could take advantage of with the previous lighter rod. Personally, I would use Mahle pistons as a road race type piston only, and not a drag race piston. Hope this didn't confuse you, it was kind of a ramble.

 

since you're curious, no we're not using Mahle pistons Not that there is anything wrong with but we're using a different manufacturer. From what I've seen they look like to be very high quality pieces.

 

Cool, do you have pics of the pistons that you are using in your 23RR motor?

 

i have spoken to other piston makers & getting down to a light weight like that isnt very difficult, you jst use a shorter piston pin.

lets face, that steel tube is a hell of a lot heaveir than the aluminum of the piston.

i am cosidering the cp piston, as they can make the piston reasonably quick, run ~ .004 ptw clearance. mahle doesnt make a 2.4l piston & they are exptremely busy right now & cant make a custom piston quickly @ the moment.

why does weisco run such a tighter ptw clearance than J&E? arent they the same forgings / maker or am i missing somethnig...which is most likely the case.

 

I'm currently building a V8 engine for a Cobra with Mahle pistons...I was very suprised when I saw them, they are definitely very lightweight compared to the normal forged pistons you see from Ross or Wiseco. They also have a dull non reflective finish to them, and do not have the typical mirror finish.

 

VW engines come stock with them . We have made VERY good power with them... I don't have them anymore in my car (VW) I now use Ross

There are guys with the 225 TT's making over 700 whp on stock pistons with upgraded rods

 

True story! i am using mahles in my STi and they are very loud at idle when cold, but the slap goes away after about 20-30 seconds.

 

Porsche's use Mahle....Very good quality...Really depends on budget and what you are looking to do...

 

A couple of STI's with them have had issues with them:

http://www.iwsti.com/forums/showthre...=33750&page=74

http://www.iwsti.com/forums/showthre...=64181&page=14

If your going to all the trouble of changing them, I would go for 2618 forged pistons and call it a day.....