Tom Pultz

If one were to build a 3.0 turbo today using a 968 block and 2.7 or modified 951 head what are the options for available pistons? Any still available for Alusil bores?

Thanks.

blade7

Do you feel lucky....

V2Rocket

zero reason to stick with alusil anymore.
nobody knows how to machine it other than what, 1-2 shops in the US.?

sleeves are the only way forward.

JustinL

I've had success with custom Arias pistons that I ordered through 928motorsports. They know their stuff with Alusil. My first set of Arias are matched to my Nikasil block and have been awesome; my second set are 3.0L 16v 9:1 pistons I'm running in my 951 Alusil block. It took a LONG time from order to delivery. Attachment 1338780

blade7

AFAIK sleeves obstruct much of the windage ports though?

Ski

Engine shop in San Antonio knows Alusil and how to machine. Call MAHLE, you would be surprised how they work with people. The pistons JAB Racing did are the ones LR now sales. 1st post in 5 years LOL. I found an 88 for sale and was just looking to see if it was for sale on here anywhere. Good luck Tom.

https://lnengineering.com/products/m...930130214.html

sm

Does Mahle offer lightweight pistons for the 3.0l block?

Chris White

yes, they will custom make anything you want. i use a lot of 3.0 and 3.1 16v turbo pistons from Mahle (8v too)

Tom Pultz

So, I'm looking at the Mahle "968 Turbo" pistons sold by LN Engineering. They say that they are specifically for Alusil and not for Nikasil, but they are first oversize at 104.5mm, which means boring the block, which them removes the Alusil. I asked Millennium Tech about this and they said lots of people use these pistons with their Nikasil type coating. I've asked Mahle about this but have not gotten a response. BTW, the pistons as advertised for 968 Turbo are for an 8-valve head as confirmed by Mahle.

So, I guess Mahle could make a set of 3.0 pistons to work with a stock bore Alusil block? That would save money, but I know Nikasil is stronger.

Chris White

the 944 block is all cast alusil, you can overbite it but then you need to have the alusil finished using the proprietary factory method of fleets and special paste.
best bet is nikasil coating to what ever diameter you want and get uncoated pistons

blade7

I was planning to buy a set of those Mahle 968 turbo pistons quite a while back, then someone on here that used them, posted pics of their Alusil scuff up...

GPA951s

not true, I purchased all the tooling from sunnen.. and my friends machine shop does the bore/ hone on his ck-10..i now have 2 full racing seasons on the very first engine i did and runs awesome and pulls hard @ 1 bar.. wossner pistons at 100.5 and molinar rods.. i have 3 more engines im doing this winter.. one will be for sale in the spring intake to pan ..
any machine shop can do it. The just need to follow sunnens directions to the letter.. its time consuming . Three different sets of stones and the final an30 paste on felt pads.. once you do it , way easier and by far cheaper than sleeves. Initial layout for the tooling was $800 but gives you enough stuff to do 30 blocks.. now a bore/ hone is only $400 for the machine time..

p.s. I was at the performance racing industry show in indy in 2018 when i spoke to the sunnen folks.. when I looked at the brochure for this huge cooperation i couldn't believe my eyes… what was on the cover? A 944 block!

Oddjob

Chris - can you use factory 951 pistons with a Nikasil plated block? What about rings with the Nikasil? A local shop told me some years ago to use 964/993 Turbo rings with the Nikasil, not 951 rings.

V2Rocket

$400 machine time but $1500+ pistons...

or $1500 sleeving and $400 pistons

i was gonna build a hot 16v engine back in 2019, picked up Wossners and a block that was supposedly ready to run. turns out it never got final honed. couldn't find a shop within 500 miles of me that knew what Alusil was. even called Sunnen for referrals and they had no idea.
i know of a shop in CA that can do it, a shop in the north somewhere that can do it, and i guess your place too. not great odds unless you like shipping engine blocks.

whereas any competent shop can fit sleeves that can be rebored as needed for any piston you could dream of.

inability to do that 16v motor is what made me sell off all my 944 engines and engine parts and start a swap.

Mike Goebel

Easy Peasy, Just send it to Germany.


Mike G.