Best Pistons Choice ?

[The Dan]

Have had a friend just rip out his mahle's because the teflon delaminated. Arias FTW!

Yeah Arias are quite good if you want uneven bore sizes and massive differences in weight.

bit unreallated, but what do you guys do when the ring gaps are to big, i cant find file back rings anywhere

my engine was on hold for 6 fkn months cause my engine builder couldnt find file back rings, these guys are pretty pedantic though, I work in the industry and email/called je/acl etc and the wholesalers and was told by all to just use the rings that were made for the 86.5 bore size that came with the pistons as i could find file back rings anywhere, as i was sick of waiting for over 1.5 yrs in total for this engine to be put together i told them to use the acl rings that came with the pistons

just wanted to know what your guys take on it would be

There are no rules saying you can't file a standard ring. If you buy a piston set that comes with recommended rings and their gaps, how do you think they expect you to adhere to their gap specifications for blown applications or drag/nitrous etc if you can't alter the gaps. They expect you to file them. They are not known as 'file back rings' because it's an old term that is misleading. All rings can be filed.

[The Dan]

And as for squirters. Keep them there. Take your pistons to a good engineer and have them machined or ground to relieve the oil squirter clearance.

[rbs14kouki]

And as for squirters. Keep them there. Take your pistons to a good engineer and have them machined or ground to relieve the oil squirter clearance.

is this going to change the balance of the piston ??? should i rebalance everything , cause it's allready done !!!!

Edited May 16, 2009 by rbs14kouki

[The Dan]

is this going to change the balance of the piston ??? should i rebalance everything , cause it's allready done !!!!

Yes!!!!!!!!!!! you will !!!!! need to rebalance!!!!!!!!!!!! them!!!!!!

[Swiper the Fox]

And as for squirters. Keep them there. Take your pistons to a good engineer and have them machined or ground to relieve the oil squirter clearance.

DO NOT MACHINE THE PISTON...this is not necessary. With a bit of 'actual' thinking the piston oil jets can be fitted with the Mahle pistons. More material than Mahle recommends be removed needs to be machined from the piston to get it to sufficiently clear the rib and skirt. Machining the pin rib on these pistons is a big no-no. Brands other than Mahle can be notched because its simply removing material from the skirt and not the pin rib. Look at it and think about it and you should be able to work it out...it took me an hour of fiddling to get the 1st one right and 10mins to do the rest.

Edited May 17, 2009 by DiRTgarage

[Guilt-Toy]

lol.. Dan strikes again

[Angus Smart]

Haha, yeah i'm glad my engine builder has his thinking cap on it didnt take him much time at all to work out a better way!

[Guilt-Toy]

Haha, yeah i'm glad my engine builder has his thinking cap on it didnt take him much time at all to work out a better way!

yes lets all let Mr Dirt know how much we him

he is not all that a loveable fellow.. infact sometimes he is a downright pain in the ass

lol

[rodger1]

can't you just put thicker washers under the squirters to space them down a little?

[The Dan]

DO NOT MACHINE THE PISTON...this is not necessary. With a bit of 'actual' thinking the piston oil jets can be fitted with the Mahle pistons. More material than Mahle recommends be removed needs to be machined from the piston to get it to sufficiently clear the rib and skirt. Machining the pin rib on these pistons is a big no-no. Brands other than Mahle can be notched because its simply removing material from the skirt and not the pin rib. Look at it and think about it and you should be able to work it out...it took me an hour of fiddling to get the 1st one right and 10mins to do the rest.

Mahle don't recommend anything in regards to material removal. You only have to take away 2mm from the skirt to make them fit.

Using washers to space them up can be risky but if you choose the right washer material and don't go too thick, then yeah...can be done that way also. Have never had an issue before with piston modification as long as it is done correctly.

lol.. Dan strikes again

Who are you again?

[Angus Smart]

yes lets all let Mr Dirt know how much we him

he is not all that a loveable fellow.. infact sometimes he is a downright pain in the ass

lol

I didnt use mr dirt for the build.. but starting to wish i did, still no motor back yet.. but i've surely saved some pennys in the meanwhile

[R31Nismoid]

lol.. Dan strikes again

Come on - Enough following around and making digs at people.

FI is a good place to be most of the time - dont ruin it by silly posts

[Swiper the Fox]

Mahle don't recommend anything in regards to material removal. You only have to take away 2mm from the skirt to make them fit.

Using washers to space them up can be risky but if you choose the right washer material and don't go too thick, then yeah...can be done that way also. Have never had an issue before with piston modification as long as it is done correctly.

Who are you again?

My friend up here i have been staying with and working for (building his 8 second VL drag car) builds Supercar engines for Triple 8 racing and they deal direct with Mahle in the states. They dont recommend piston modification but if necessary no more than 60thou be removed from the skirt and absolutely no material be removed from the pin rib (which is where the top of the oil jet comes in contact with) which cannot be spaced enough without the jet fouling on the crank counterweight.

More needs to be done than a simple spacer to get it to all work correctly. Chopping up pistons is rough and bodgy in my opinion. Especially when it doesn't need to be done to get it to work.

[proengines]

is this going to change the balance of the piston ??? should i rebalance everything , cause it's allready done !!!!

You don't need to rebalance everything, just make sure the pistons are all the same weight as each other once you're done. You can bump a little off the locating pin on the oil squirter to move it where you need it. It won't hurt to put a small notch at the bottom of the skirt to clear the squirter, just make sure it's machined cleanly and the edges chamfered. Don't cut into the rib, the squirter will line up under the rib if you bolt it into the standard location, that's why you need to twist it around a little.

It's also worth checking the pin offset in the piston to make sure you put the pistons in the right way, don't rely blindly on an arrow on the top of it to guide you, the arrow doesn't necessarily point to the front. Many Mahle pistons have an arrow or a squiggle that points to the flywheel, not the front, others have the arrow pointing to the front.

They're nice pistons and I've used them in quite a few engines but for most engines you can't go past a set of Wiseco's.

[Swiper the Fox]

You don't need to rebalance everything, just make sure the pistons are all the same weight as each other once you're done. You can bump a little off the locating pin on the oil squirter to move it where you need it. It won't hurt to put a small notch at the bottom of the skirt to clear the squirter, just make sure it's machined cleanly and the edges chamfered. Don't cut into the rib, the squirter will line up under the rib if you bolt it into the standard location, that's why you need to twist it around a little.

It's also worth checking the pin offset in the piston to make sure you put the pistons in the right way, don't rely blindly on an arrow on the top of it to guide you, the arrow doesn't necessarily point to the front. Many Mahle pistons have an arrow or a squiggle that points to the flywheel, not the front, others have the arrow pointing to the front.

They're nice pistons and I've used them in quite a few engines but for most engines you can't go past a set of Wiseco's.

Spot on...nice of you to give the game away Greg...lol.

If done correctly there is no need to notch piston...a correct thickness spacer and an offset of the jet should have everything sweet.

[The Dan]

Spot on...nice of you to give the game away Greg...lol.

If done correctly there is no need to notch piston...a correct thickness spacer and an offset of the jet should have everything sweet.

I didn't pick you for the 'my camshafts are secret spec' type Paul?

Never had to turn them before and didn't have any issues with the crank clearance either. I did space the jet away by 1mm and have taken 1mm out of the piston skirt only. It cleared with the spacer but notching the piston was as a safety. Have had no issues spinning it up to 400rwhp and engine has 20,000k on it now.

But good advise is always taken on board so I'll check out that method on the SR I'm doing at present.

[Swiper the Fox]

I didn't pick you for the 'my camshafts are secret spec' type Paul?

Never had to turn them before and didn't have any issues with the crank clearance either. I did space the jet away by 1mm and have taken 1mm out of the piston skirt only. It cleared with the spacer but notching the piston was as a safety. Have had no issues spinning it up to 400rwhp and engine has 20,000k on it now.

But good advise is always taken on board so I'll check out that method on the SR I'm doing at present.

lol...i like to make people have a little think for themselves first. The method i worked out is the best in my opinion and can be done without the need for a third party (machinist) to be involved.

See how it goes on the SR and let me know what you think and what the results are.

My camshaft specs are easy...i always use the biggest.

[Guilt-Toy]

Who are you again?

i am that guy who works on people's cars at his mummys place

[N1GTR]

Come on - Enough following around and making digs at people.

FI is a good place to be most of the time - dont ruin it by silly posts

i am that guy who works on people's cars at his mummys place

[Swiper the Fox]

Dan just make sure you have a nice medium between clearing the rib and clearing the conrod as too much offset can cause rod clearance issues.