Pistons for turbo engine

Hey, I need some advice regarding purchasing pistons/rings... Im looking into lower my compression in a bmw s52 engine, so far I have looked at JE,CP,ROSS and Venolia pistons... and total seal rings. From the opinions I gathered im leaning toward buying Venolia pistons... is there anyone here that experienced those? opnions? ;) I was also looking at total seal rings but I had people tell me they fail quite often.
Any advice/opnions etc on pistons and rings would be great.

Thanks in advance.
Tom

Hey, I need some advice regarding purchasing pistons/rings... Im looking into lower my compression in a bmw s52 engine, so far I have looked at JE,CP,ROSS and Venolia pistons... and total seal rings. From the opinions I gathered im leaning toward buying Venolia pistons... is there anyone here that experienced those? opnions? ;) I was also looking at total seal rings but I had people tell me they fail quite often.
Any advice/opnions etc on pistons and rings would be great.

Thanks in advance.
Tom

I've used Aries an Venolia pistons with good luck. The Total Seal rings i've been using for 20 years and never had a problem with them.

Were any of the engines that had totalseal rings turbo-d? If so how much boost were you running?

Tom

Were any of the engines that had totalseal rings turbo-d? If so how much boost were you running?

Tom

All but 3 were turbo'd, and they were supercharged.

Im running Ross pistons on my Contour. Would never deal with them again! I dont know who is running that place, but they need to get a clue.

I sent them a stock piston and told them I wanted some 8.5:1 compression pistons. How hard can that be? :screwy: Get them back, and the skirt design is too long and pistons 1 and 6 would hit the bottom of the block when rotating. All they had to do was use the stock skirt design.

So I send them back, and this time they fix it but they send the wrong rings. Send them back AGAIN, and once I receive them they send the right rings, but forget to send new wrist pins since they were previously installed. NEVER AGAIN!

I like Wiseco, but all of the ones you listed will do the job. But its prolly best to look for one that makes and advertises pistons for your specific application. Like beyondloaded's incident, I wouldn't wanna deal with something like that if I can just buy pistons already set up for my application. Good luck.

BMW's choice of supplier of high performance pistons is Mahle Motorsport. They are probably not the cheapest but they can supply high quality pistons, liners, pins and rings according to customers needs.

If the engine are suppsoed to be supercharged (mechanical compressor or turbocharger) it's very important to get a strong ring land which often is a weakness.

To minimize blow by gases it's also important that the parts are matched for eachother and has a suitable design for the purpose. This does also involve the cylinder (block or liner).

BMW's choice of supplier of high performance pistons is Mahle Motorsport. They are probably not the cheapest but they can supply high quality pistons, liners, pins and rings according to customers needs.

If the engine are suppsoed to be supercharged (mechanical compressor or turbocharger) it's very important to get a strong ring land which often is a weakness.

To minimize blow by gases it's also important that the parts are matched for eachother and has a suitable design for the purpose. This does also involve the cylinder (block or liner).

For hi-performance BMW recommends MaxSil or JE pistons as these pistons expansion rate are similar to the engine block which is very important for good service and long life.
Where as the Mahle pistons are suitable for OEM replacement pistons.

BMW's choice of supplier of high performance pistons is Mahle Motorsport. They are probably not the cheapest but they can supply high quality pistons, liners, pins and rings according to customers needs.

If the engine are suppsoed to be supercharged (mechanical compressor or turbocharger) it's very important to get a strong ring land which often is a weakness.

To minimize blow by gases it's also important that the parts are matched for eachother and has a suitable design for the purpose. This does also involve the cylinder (block or liner).

yup yup. Ring lands are always the first to go on my engine. Like cookie dough weak.

Another thing I have heard is really good is phosphate coating. Helps with really high heat.

yup yup. Ring lands are always the first to go on my engine. Like cookie dough weak.

Another thing I have heard is really good is phosphate coating. Helps with really high heat.

Thats why piston mfg. make pistons for N/A engines and supercharged engines. The loads on the blown engines ring lands is much higher on blown engines than N/A engines.
I think your thinking of molybdenum coated pistons.

BMW Motorsport are using Mahle Motorsport pistons in their racing engines (like their F1 engine), just like the VW-Audi Group (Le Mans, GT, WRC), Ferrari, Toyota, Renault, Peugeot and Citroen are. These pistons are usually forged of high silicon alloys, or RR58 based alloys but AlBe and MMC materials have also been used.
http://www.mahlemotorsports.com/obj.nsf/74BE3C2CF01E147685256E3C0064E644/$FILE/page22.pdf

A piston will not expand like a block since materials and temperatures differs. The shape of the piston and the clearence between the block/liner and the piston is therefore matched so the piston will fit in the cylinder perfectly at full running temperature.

Pistons are sometimes coated for a better run-in or wear resistance/friction reduction.

With turbocharged engines there is usually a need for hard anodized ring grooves.

Saabjohan, once again you only post what you've read and not fact.

"BMW Motorsport are using Mahle Motorsport pistons in their racing engines (like their F1 engine), just like the VW-Audi Group (Le Mans, GT, WRC), Ferrari, Toyota, Renault, Peugeot and Citroen are."

There is 3 company's that stamp piston blanks and Mahle isn't one on them. Mahle only machines them. Each of the above car mfg's has Mahle machine the piston's to there specs. as they do other companys. BMW is using Mahle pistons as well as other mfg. pistons in there engines.

"With turbocharged engines there is usually a need for hard anodized ring grooves."

With turbocharged engines it much better to alloy "TIBOR" with lead free, no copper in the aluminum than it is to anodize the aluminum.

As for who uses what depends on who cuts the best deal. I'd say I run Coke Cola in my car if they payed me enough.
I'd also piss on a spark plug if it cut 1/10 off my times.

uhm my email notofications didnt work... thanks for all the responces currently CP pistons are $1100 for a set(6) with pins/rings. Is anyone aware of places that sell those retail? (custom made i guess) and aprox pricing on them. I called some of the numbers on their website but most of them dont sell retail.

Tom

Thats why piston mfg. make pistons for N/A engines and supercharged engines. The loads on the blown engines ring lands is much higher on blown engines than N/A engines.
I think your thinking of molybdenum coated pistons.

http://ka24de.com/

Its the very first link. They advertize phosphate coating.

http://ka24de.com/

Its the very first link. They advertize phosphate coating.

I stand corrected. Now I'll have to do some research. I know molybdenum is super for heat shielding and wear, but phosphate, I'm not sure, but i'll find out.
Thanks for the correction.

Now that I think of it I might as well try to get Mahle pistons, does anyone know where is a place that sells em retail? (most of the places on their websites sell only larger quanities)

Tom

Saabjohan, once again you only post what you've read and not fact.

"BMW Motorsport are using Mahle Motorsport pistons in their racing engines (like their F1 engine), just like the VW-Audi Group (Le Mans, GT, WRC), Ferrari, Toyota, Renault, Peugeot and Citroen are."

There is 3 company's that stamp piston blanks and Mahle isn't one on them. Mahle only machines them. Each of the above car mfg's has Mahle machine the piston's to there specs. as they do other companys. BMW is using Mahle pistons as well as other mfg. pistons in there engines.

"With turbocharged engines there is usually a need for hard anodized ring grooves."

With turbocharged engines it much better to alloy "TIBOR" with lead free, no copper in the aluminum than it is to anodize the aluminum.

As for who uses what depends on who cuts the best deal. I'd say I run Coke Cola in my car if they payed me enough.
I'd also piss on a spark plug if it cut 1/10 off my times.
Like usually you don't have a clue what you talk about!

Mahle Motorsport machine their racing pistons in Fellbach outside Stuttgart in Germany. Forgings are produced elsewhere within the Mahle group.

There are different materials used in "racing" pistons, ranging from RR58 to high silicone alloys. Some are also made in an anuminum matrix composite with up to 30% SiC or AlBe, those are however not forged.
Anodized ring lands will introduce a higher hardness/surface strength in all aluminum pistons.

Like usually you don't have a clue what you talk about!

Mahle Motorsport machine their racing pistons in Fellbach outside Stuttgart in Germany. Forgings are produced elsewhere within the Mahle group.

There are different materials used in "racing" pistons, ranging from RR58 to high silicone alloys. Some are also made in an anuminum matrix composite with up to 30% SiC or AlBe, those are however not forged.
Anodized ring lands will introduce a higher hardness/surface strength in all aluminum pistons.

I could care less where Mahle pistons are machined, and I'll tell you for fact, Mahle does not have a forging plant within the Mahle group. We (I) use to forge the blanks for Mahle before we sold out to Alcoa Aluminum.
As I have a Master degree in Metallurgy I'll tell you point blank, you have no idea what makes up the chemistry of the aluminum for pistons.
I'm also well aware what anodizing does to aluminum.
Being your so up to date with metallurgy what is tibor?
Why is vacuum investment casting as good as some types of forgings?
Why are forged aluminum parts heat treated after forging?