Pistons & Barrels for big bore upgrade
 

Hi Guys...I'm planning a big bore upgrade to a 993 varioram M64 and getting lots of confusing info over which P&B's to use. I'm looking for a 3.9 / 4.0 - LN Engineering & Capricorn offer combinations but speaking to Motor Meister they offer 'Biral' barrels....never heard of them. Can anyone comment on the best options? Cheers, Jim

My comment? Stay away from Motomeister, I've been here for 6+ years and have yet to hear the first positive comment on Motormeister.
If you do a search on this forum on MM, you'll find out that they are not a business you want to deal with.

Others will chime in on the technical portion of your question.

STOP!!


Do a search on MotorMeister. They are the biggest scammers in the "business". They will take your money and give you a hand grenade of a flat-6.

Use someone like Henry Schmidt of Supertech or Steve Weiner @ Rennsport Systems.

That said, Nickies are highly regarded. Top-notch parts. They are better than Mahle in some ways. They also work well with JE pistons- the alloy thermal expansion rates are matched more closely than with Nickies and Mahle pistons or with JE pistons and Mahle barrels. Charles Navarro at LN Engineering is very reputable and a wealth of knowledge.

"Birals" are what the old cylinders from the late 60's and early 70's were called. They were a cast-iron liner with Aluminum barrels (with the cooling fins) cast around the iron core. The iron was the hard wear surface while the Aluminum was lightweight support and also cooled better.

Birals are quite inferior to Nickasil, which is the Mahle trademark for a high-silicon Aluminum alloy barrel with a thin, electro-plated Nickel-Silicon-Carbide layer on the inside wear surface where the piston rings run. This coating is much harder and has much less friction than any of the other previous constructions. The 917 made about 25 more horsepower by this single change alone.

Another term you might hear is "Alusil". These cylinders were made by Kolbenschmidt for the some 911SCs. It had about the same performance characteristics of Nickasil but was eaasier/cheaper to manufacture. This is an Aluminum alloy cylinder barrel with a high Silicon content. The inside cylinder walls are then etched to expose the hard microscopic chips of Silicon. This is the hard wear surface BUT requires a different, special, iron-coated piston to run properly with little friction, wear, and without "gumming up" the rough silicon.

Lastly, there was the "Chromal" barrels for the Fuhrmann four-cylinder, four-cam Carrera racing engine. This was Aluminum coated in hard Chromium for wear-resistance.

The cross-hatching pattern is critical for all of these to retain just the right amount of oil on the cylinder walls to assure smooth, smoke free running once the rings seat.

i Guys,

thanks for this - its difficult for me trying to deal with the States (I'm in UK) where everything is sooo expensive. Good intel on Motor Meister - I haven't been happy with there correspondence, they wont answer any direct questions etc. I think I'm going to go with the Nickies & JE pistons, R&R rods, ARP bolts from LNE, ship 'em to UK and get a UK company to build the motor up for me.

Do you know any guys out in States who can do good headwork?

I understand that the limitation on making power on the M64 is limited by the varioram - has anyone experience of the PMO throttle bodies?

I sure do,....:) :)

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The V-Ram single-throttle intake does impose limitations in camshaft profiles and I'd stick with things such as factory RS cams if you want the engine to idle.

Naturally, an ITB system has no such restraints and offers much better throttle response to boot. These intakes do require different Engine Management systems such as Motec.

Sooo subtle.

Mazdaholic- Steve's doing my 3.6 heads right now. Ship yours across the pond and he'll take good car of you. That would include P&C's, cams, etc.

I would also highly recommend Steve @ Rennsport. He just completely rebuilt mine and they look great. He is also a wealth of information!!! That alone is worth the price.

We aim to please,.....:) :) :)

I have s set of new CWM (made by LN i believe) P&C's with JE's 102mmn (3.8) 10.5:1 which I am not going to use now as I'm turbo charging PM me if you want them, they will be in the classified area next week.