Mahle Piston Review

[Hijacker]

I'll hopefully be talking with someone at Mahle soon that can help do something about this in the future. The one guy I talked to doesn't deal with the sport compact line and, consequently, hadn't heard of this particular problem. This should have been addressed in design of the piston, but given different tollerances of blocks, especially seasoned blocks, it's possible to imagine that their design block didn't have this worry. Either or, I'm hoping to convince them to alter future production pieces to account for the squirter. The Mahle piston is a great item, but unless it is a truely drop in affair, not many people will bother themselves to get it.

[mestizo]

Dam Bart sorry to hear about your arm. I am digging your build tho!

[Hijacker]

Thanks for the compliment rob! The break is old news now thankfully. I've been back to full steam for a while.

[mestizo]

LOL sorry i didnt realize how old this thread was.

On another note did u get a chance to read my write up? If so you think it's ready for Nico? Let me know.

[Hijacker]

I read it, and it looks great!

[homeslicej2]

I'll hopefully be talking with someone at Mahle soon that can help do something about this in the future. The one guy I talked to doesn't deal with the sport compact line and, consequently, hadn't heard of this particular problem. This should have been addressed in design of the piston, but given different tollerances of blocks, especially seasoned blocks, it's possible to imagine that their design block didn't have this worry. Either or, I'm hoping to convince them to alter future production pieces to account for the squirter. The Mahle piston is a great item, but unless it is a truely drop in affair, not many people will bother themselves to get it.

My thoughts exactly. Hopefully they will get it sorted out so that the pistons are truly drop-ins.

[Hijacker]

Good news. I just got off the phone with Tony Ford at Mahle. He's the guy in charge of the sport compact division for the power pak line. I'm going to be taking some measurements and pictures this weekend and he said they'll make the alterations to the pistons for future releases and this won't be an issue.

[homeslicej2]

^

[Mouse6933]

hey bart glad to see some things ahve been going in a better direction, after you spoke with tony. did u get the impression that he had never seen an sr before and that they only took dimensional spec's and then designed there pistons off of numbers nd not on an actuall application... i understand that alot of companies may do this in making various parts, but it seems like a pretty crappy way of designing thing such as pistons, and for such a well known company.... But im glad to see you have gotten intocuh with them and youll ahve your car up and running. I know on my application its not the skirt thats making contact... this was my initial thought due to all the other piston deisigns haveing notches on the skirt, its actualy on the area where the wrist pin is, the design of that area taper in much more than on any other pistons design and thats where my squirters were making contact, sooo maybe this will help on yours too. best of luck to you bro

myles

[redtop91]

Good news. I just got off the phone with Tony Ford at Mahle. He's the guy in charge of the sport compact division for the power pak line. I'm going to be taking some measurements and pictures this weekend and he said they'll make the alterations to the pistons for future releases and this won't be an issue.

ETR?

[Hijacker]

Ryon, what's ETR?

Here's a pic I photochopped up last night to give myself an idea of where I'll need to make my alterations.



I found the center point on the stock piston and then drew a line to the center of the notch. Then I transposed that line onto the Mahle piston to give me a general idea of where the cuts will be made. I'm currently waiting to hear back from Mahle if the corner will be ok to grind down. I don't see it being a problem, however, having manufacturer approval helps ease the mind.

I'll know where the real cut will need to be made once we pull the pistons down this weekend.

I measured my last stock piston, and from the crown to the apex of the notch is 1.934". Nissan does allow for like .050" of clearance though. I just know that the Mahles are barely touching. The squirter arms that broke off barely have a worn spot where the piston contacted. All the damage was done to them as they fell through the crankcase. I have a feeling that they barely came into contact once things heated up and was under pressure and even then it took a while for them to finally anneal and break. The analogy I used was like that annoying kid that lightly punches you in the arm. It doesn't hurt until the 100th time when you start to bruise up.

[homeslicej2]

Ryon, what's ETR?

Estimated Time till Redesign?

[Free Motion Tail]

What's up Bart. You should get Mahle to send you a free set of the revised pistons whenever that happens.

[Hijacker]

At this point, I don't want to have to tear the motor down any more than I have to, Mark nor wait more than I have to.

[redtop91]

Ryon, what's ETR?

Estimated time until Mahle repairs the piston. I really like these pistons so I want to wait on them but time constraints might make me go another route .

[Hijacker]

I can ask Tony. I think they make the pistons as they're needed anyways, so as soon as we make the modifications needed, when you order a set, they should come to you with the notch. I can try to get some confirmation on that for ya.

[Free Motion Tail]

i[QUOTE=Hijacker]At this point, I don't want to have to tear the motor down any more than I have to, Mark nor wait more than I have to.[/QUOTEI

I know... Still...

[Hijacker]

I updated the main post to include my solution for the squirter issue. I had completely let it slip my mind

[redtop91]

Hey Bart is it possible for the squirters to swivel back?

[Hijacker]

I'd be amazed if they did. You're moving them clockwise towards the center, so when you tighten the bolt down, you're just tightening the squirter towards the center position even more.

If the bolt were to back off enough to let the squirter swivel back, you've got bigger problems than a broken squirter.

[TRBOMOFO]

did mahle get the new design implemented and out in the market?

[Hijacker]

There was nothing to change once it was all said and done. The solution to the problem is reclocking the squirters like I put in the OP

[TRBOMOFO]

i guess i a m taking off the oil pan tommorrow and hoping that there is no oil squirters in the bottom haha

omg

[Hijacker]

I thought you said you reclocked your squirters?

[TRBOMOFO]

yep

but i changed the oil and nothing flowed out so maybe i got lucky but i dunno i will find out tomorrow

[Hijacker]

If you reclocked them, you're fine. They don't contact the sideskirts like I had originally thought. I edited the OP to reflect that

[Hijacker]

Just to clarify the OP a bit and to assure readers, the part past UPDATE is current and what I have done to make the squirters work with the pistons. The sideskirts do not contact the squirters, it's the inside support casting that bridges the wrist pin and the side skirt. I've received a few emails about the subject, so I figured I'd clear it up.

[TRBOMOFO]

i took off my oil pan and i found some goodies



so i am going to do what you did Hijacker and do the reclock this time

Does anybody know of a good deal on some oil squirters?

[Hijacker]

West Covina (The Nismo Shop) can get them and sometimes have them in stock for about $25 per jet.

I could have sworn you described what you did to them as reclocking them. You said you lopped off the locator pin and swiveled them out of the way of the skirt support.

[TRBOMOFO]

na i guess we had miss communication i just put them back in the way they came out i check clearances but i forgot about heat expansion so i made a mistake

oh well i will get some more work done

what is their number?