3.0 to 3.2 benefit??

[Schuey]

what would be the benefits of going with a Mahle 3.2 piston/cyl set (93010398910) on the my 3.0 case? with 10.3:1 compression...

what else would I need to do?

I have a chance at a deal on a like new set (NOS) for $1500 is this a good deal?

[dd74]

Are they stock pistons from a 3.2 engine? I don't know if those will work with a 3.0.

If you short-stroked your 3.0 to a 3.2 using aftermarket Pistons, I think the increase in power is 6%. It might be double that if you stick in a 3.2 crank and larger pistos to make your engine a 3.4...

[Schuey]

from what I understand this is a complete high compression (10.3:1) setup with pistons and cylinders...in my ever search for more power and good deals I thought I may just buy these...it's from the local (3hrs away) porsche dealer...I thought I'd add my PMO's, swap out my pistons/cyl with these and bam...power

[MotoSook]

If they are the 98mm Mahle P/C's made for a 3.2 base engine(versus a 3.0 base engine), then you should be able to use them. If they are in great shape 1500 is a good price. 10.3:1 is a bit high and dual plugs would be required.

I'm always drooling over the 3.2 930/02 engine that "cstreit" has! Guys that I have talked to who have driven a 3.2 short stroke love 'em!

Edit (PS): If you do get them, contact me about selling your 95mm Mahle set out of your engine, please.

[dd74]

Hmmm...if no one else chimes in on this thread - and because you might be under a crunch time-wise to buy these (there are 3.2 guys out there who may want this setup for their USA engines, you know), I'd call a good shop like TRE to confirm if the pistons and cylinders can be adapted to your 3.0. There may be all sorts of issues, like Motronic as opposed to your CIS, etc.

[MotoSook]

If the pistons will mate to your 3.2 rods (small ends are different between the 3.0 rods and 3.2 rods)...get them. 10.3:1 with dual plugs and carbs is doable....

This been discussed in the rebuild section...

[dd74]

Souk - isn't Shuey talking about an engine that is currently a 3.0? Why would he have 3.2 rods in a 3.0 engine?

[MotoSook]

OOPS! You're right David....I was thinking backwards.....he should make sure the pistons will work with his 3.0 rods....better

[dd74]

Hey Shuey, TRE's building a 3.4 now. I'd give 'em a call...quickly

[emcon5]

There are 2 ways of getting to 3.2 L from 3L. You can go with a longer stroke, requiring a different crank (which is the route the factory took), or you can increase the bore from 95mm to 98mm.

Assuming you are talking about stock 95mm Euro 84-89 3.2L P&C set, it won't work without additional work. The wrist pins are different size. The compression is also too high for single plug on pump gas.

If they are 98mm, (which I doubt, based on the part# and the price) snap them up. That is about half price for a 98mm set.

Tom

[Wayne 962]

Some clarity here:

The pistons and cylinders that you get must be matched to the proper crank and rods. Therefore, a 3.2 Piston & Cylinder kit must be manufactured to work with the 3.0L crank (this is a non-standard setup). Stock 3.2 Piston and Cylinder kits that would work on the 1984-89 engines *will not* work in the 3.0. The difference is that the hole for the piston pin is offset differently.

On the other hand, the cylinders themselves are almost exactly the same and can be interchanged. You just need to make sure you get the right pistons with the proper piston offset.

-Wayne

[Schuey]

well, I spoke with Steve at Rennsport, he said my PMO's (new) would need to be rejetted and I should twin-ignition it also...


wayne, I'm a bit confused on the piston ping...if I get these your saying they will not work on my 3.0?

[MotoSook]

Perhaps my comprehension skills need work..or I'm just too lazy..but! I underestood Shuey's initial post as saying that he found a set of p/c's to make a 3.2 engine out of his 3.0. But now that I read it, it appears he found 95mm p/c's from a stock 3.2, which won't bolt onto a 3.0 lower end to make a 3.2 short stroke. Wayne has pretty much cleared it all up.

Shuey you'll need 98mm p/c's design/made for a 3.0 lower end. You can't just use the stock p/c's from a 3.2 Carrera to make a SS3.2 out of a 3.0.

A set of Mahle 98mm P/c's for a 3.0 to make it into a SS3.2 is expensive...over $3000 retail!

[Superman]

I'd love to drive a 3.0 that has been converted to a 3.2 by installing the 98mm Max Moritz P&Cs, along with carbs and an exciting cam. As much as I enjoy my ferocious stock 3.0, I'm guessing the short stroke 3.2, with carbs and cams, would be at least TWICE as fun.

[MotoSook]

Superman, Chris Streit has a MM 3.2 built on a 3.0 Carrera case in a race car! Torque and free reving!

I'd love to buy the thing, but I'd have to buy the car too (don't tell him this, but I'm going to sneak the car out one night and give it a good flogging)

[Schuey]

Steve @ rennsport DID think these would work with my 3.0 so I'm confused now...

[rpiper]

I am certainly not an expert in this arena, but I will chime in as I have seen/ driven a 3.0 that had the factory's 3.2 pistons. It ran fine, but was a complete dog. I bet it didn't make more than 160hp. What Wayne is talking about is the wrist pin on the factory 3.2 piston is in a different location (further toward the middle of the piston) than the 3.0 piston. Both are the same diameter (95mm), so you will have NO displacement increase using the 3.2 p/cs because the stroke will remain the same. And the location of the wrist pin will dramatically drop the CR. (that's why that engine was so weak). So bottom line, don't buy them unless 1) you can also buy the proper crank and rods, or 2) they are the 98mm p/cs.

[MotoSook]

Well, why don't you tell us what you have and we can clear it up.

Do you have 95 mm p/c's from a stock 3.2?

Or do you have a 98mm 3.2 kit?

[Schuey]

Souk,

I'm not sure, all I was told is that they were new Mahle cyl/piston set 10.3:1 compression (euro) and the part number is 93010398910

[Randy Webb]

If Steve W. said they would work then it's a virtual certainty that they will.

But... did you ask him how much it would cost? It might be cheaper to just get a 3.2....

Then there's another option -- if the price is realy good you may be able to resell them with no loss of $$ if they aren't the best option for you.