Probe pistons (Will I be messed up?)

[Mr. Y]

Hi guys.
I'm in process of rebuilding my 7MGTE using probe +1mm pistons (purchased @ driftmotion).

Okay, I was grinding off sharp edges and found that one piston in set has wrong "front" mark (or slots for valves). See attached photo.

The question is: is it okay to install that piston with front mark pointing rear? (so larger slots will be on intake side, like them should)

My block is already machined for that pistons, so changing piston is not an option.

-figgie

Mr. Y. Keep bad language out of the titles.

 

[Mr. Y]

yes, guys, I'm fucked. Piston pin has offset and piston can't be just rotated 180*.

Aaron, wouldn't you send me +1mm probe piston? As soon as possible of course... directly to russia, using something express like DHL?

PS: I can't install it just like it is cause even stock valves will hit piston (and I run OS valves)...

 

[Doward]

Well, you answered your own question - Sorry to hear about the trouble, man! That's not a common thing to happen

 

[Mr. Y]

I don't care if it's common or not. I was waiting that pistons more than month. I bought them not from ebay, but from authorised vendor. I bought them not because they're cheap but because they were designed for 7M (not just copied from stock).

And what should I do now? I can't rebore block (already +1mm), I can't use another block (you can't use engine with different number), I can't use that piston.
Theoretically, I can find machine shop that will machine pistons so both sides will have large slots, but what's the point? It will not work, like it was designed, I will not get what I paid for.

I'm very-very-very angry now.

 

[adampecush]

I'd contact the vendor directly instead of making a post here.

 

[Mr. Y]

Why don't post here? Let everyone know quality of products they buy. And if you mean contacting probe industries - it's not an option. I can't speak English, only write (so can't call them).

PS: I'm uploading some more photos... found more errors...

 

[buckshotglass]

You should send Aaron a pm.

 

[adampecush]

Why don't post here? Let everyone know quality of products they buy. And if you mean contacting probe industries - it's not an option. I can't speak English, only write (so can't call them).

PS: I'm uploading some more photos... found more errors...

I meant contacting the authorized vendor (on this site) your purchased them from directly.

impressive english writing by the way....no way in hell I could write in russian.

 

[Mr. Y]

couple more photos...
What do we see? 5 of 6 pistons (on the right) have deeper slots at intake side (like they should) but look at them from the bottom. There are _less_ material under them! So exhaust side (with small slot) has thicker crown and intake side (deeper slots) has thinner. Is it normal?

And look at the "bad" piston now (left). It has messed up slots, but material at the bottom look more logical... more material under deeper slots.
What do you think about it?

And I'm posting a side view too (to see pin offset). Can you determine now, does "front" mark pointing right?

PS: now I'm considering two ways:
1) machine all that pistons so they will have equal slots both sides (intake and exh)
2) order custom set, rehone block.

Tech guys (IJ, suprarich, Doward, Aaron, etc) chime in.

 

[Mr. Y]

I'll send PM to Aaron right now, but I want some other technical experts to post their opinions too... If that pistons don't look good enough to handle 600+ rwhp, I won't use them. I was running 1.6bar of boost on stock pistons and they were holding but It didn't feel reliable... So the whole rebuild is most for reliablity improvement...

 

[figgie]

Mr. Y.

Forgot to tell you, keep the cursing off the thread titles. Inside the post is fine. Remember, people do read these at work

The word "fuck" popping up would not be a good thing.

 

[Mr. Y]

to figgie: I see, okay. I'm trying to be polite most part of time, but that problem really driving me mad... You can't just go and buy anything for MK3 here, you have to wait for weeks (4 or even more)... And all parts become +30% at least in price... Now I think you understand me...

 

[adampecush]

if you have access to a precise scale, weigh the individual pistons and see what they come out at. They should be equal. This looks like a case of very poor quality control following manufacture.

 

[Mr. Y]

to adam:
one piston was 328 grams
two are 326
and 3 others are 324 iirc

BTW, all 6 eagle rods have the same weight. And probe+eagle assembly weights almost 200 grams lighter than stock.

 

[figgie]

Mr. Y.

Oh, I know. I completely understand. It is frustrating to say the least. You can curse inside the post to your hearts content. Not in the thread title, though

 

[CyFi6]

WOW that is a big screw up, im sorry to hear about this, i hope the express you out a new piston asap.

 

[adampecush]

to adam:
one piston was 328 grams
two are 326
and 3 others are 324 iirc

BTW, all 6 eagle rods have the same weight. And probe+eagle assembly weights almost 200 grams lighter than stock.

those weights seem like they account for the piston differences. Now that you've removed the weight from the pistons/rods, you can do the same from your crankshaft counterbalances to reduce rotating weight (if you have the means).

 

[bigaaron]

Ok, so they made a mistake. I'm sorry Probe made a mistake. Send me an email and we'll get it fixed.

but I digress...
If people think that making a thread bitching about something and cussing, BEFORE even letting me know about the problem, is going to get me to drop everything and drive to Probe and get a piston and send it express international delivery, they are sadly mistaken. Just because they screwed up your order doesn't mean it was done on purpose or that they are all like that. This is happening too often, not problems with our products, but people making threads just to bitch, not to get their problem solved. If its like that, then call Probe and have them send you a piston. I will help people however I can, but only if they ask for my help.

 

[Mr. Y]

Aaron, the main purpose ot this thread was to determine if that piston can be used. Not bitching! some time after I posted it, I made more measurements, googled a little and understood that using that piston as is isn't good idea. Then thread purpose became: what to do (considering my location)...

PS: e-mail sent.

 

[IJ.]

Confirm it's not just a case of the stamp is backwards and if it is turn it around?