Short stroke 3.2

[TimT]

we did a 3.2~ 3.4 coversion and had the cylinders re nikasiled.. the process works

send them a piston and your specs, and they will bore your cylinders and plate them to work with the pistons you are using

[Wrecked944]

"we did a 3.2~ 3.4 coversion and had the cylinders re nikasiled.. the process works"

That is a big datapoint since Andial sort of vaguely suggested this replating doesn't work well. EBS and USChrome, however, both felt very confident about it.

"My picture shows that I have no ring."

Huge, thanks. Then I shall take a copy of the pic up to NH when I see Chris this week because he has a 3.0 litre engine torn down in his garage available for inspection and comparison. It should then become very clear what, exactly, this piston ring is and how it might be effected by boring.

I also took your advice and emailed Steve Weiner at Rennsport for his expertise but have not yet heard back. No biggie. Everyone seems to be on vacation these days.

"That seems faintly rude."

No, no, no...it's okay. It is an "in-joke" between Chris and I. He knows I am hyper-sensitive to offending people and so he is teasing me. No worries...and yes, Chris, I was calling you retarded - I just didn't intend any *offense*...



Noble Knights, the search for the Legendary SC Big Bore continues...

[CamB]

Actually, I figured Chris was winding you up.

The faintly rude comment was in regard to what I wrote on the line above (think like Beavis and Butthead and their promary definition of "ring").

Make sure you report back on where you get to. I'm guessing from what I see here it might be smarter to start with 95mm Carrera cylinders.

[ChrisBennet]

Originally posted by CamB
Actually, I figured Chris was winding you up.

The faintly rude comment was in regard to what I wrote on the line above (think like Beavis and Butthead and their promary definition of "ring").

Make sure you report back on where you get to. I'm guessing from what I see here it might be smarter to start with 95mm Carrera cylinders.

CamB,
From the looks of the picture you posted, you don't have the sealing ring (or groove for it) so you should be able to use your cylinders as cores. I wish f I had my digital camera, I'd take a picture.
When Janus (the "J" is silent) comes over this week I'll tease him some more!
-Chris

[Wrecked944]

"I'm guessing from what I see here it might be smarter to start with 95mm Carrera cylinders."

Yes, CamB, the evidence seems to agree. Here is what Steve Weiner said in a reply I received today...

"Your 95mm SC cylinders cannot be bored that far. If you wish
in increase the displacement, you must purchase the 98mm ones.
There is not enough room at the top of the cylinder for the
sealing rings when they are bored.

Plus, its really cheaper to get new P/C's, too. When you
factor the cost of boring, honing, re-nikasil plating, and new
JE pistons, you have saved very little and you'll be better
off with Mahles on street cars."

A long road to get back to square one? Naw. I had nothing better to do and I really get a kick out of these little research projects - even though most are futile. If anyone else has a nutty idea they want researched to death, let me know. I'm always game.

...now on the search for the best price on those 98mm overbored Carrera cylinders...

Thanks,

[Doug Zielke]

It just so happened, Steve Weiner attended John Walker's Swapmeet last weekend, and I picked his brain on the 98mm-3.0/3.2 conversion.

First, let me say I've met very few people in our hobby as nice as Steve Weiner. He must have spent an hour or more, answering questions for a bunch of us who surrounded him, all listening with peaked ears.

What Janus writes in the post above, is essentially what Steve also told me. The good news is that his company (Rennsport Systems) is a Mahle dealer, and he *can* supply the genuine 98mm P & C kit. He also promised his price to be more competitive than "Brand A" as well.

[dd74]

If anyone's interested, I called who I think "Brand A" is to see how much something like this costs. I won't mention the person's name who I spoke with, because he initially seemed hesitant to give me his name and/or any resulting horsepower figures for the modification. Nonetheless, the dollar amount I was quoted was $8,000. That's $3,000 for the P/Cs, $5,000 for the tear down, installation and re-assembly. His horsepower figures, which as I said, he was very hesitant to give, were 20 to 25. This person at "Brand A" also seemed wary of other modifications to an SC motor once the 3.2 short stroke was performed. When asked about 20/21 cam installations and if his shop did them, he said, "You're on your own with that one." When asked what his thoughts were about 20/21s in a 3.2 short stroke, he said more than less that it was not a good idea, citing obvious CIS issues. He did say his P/Cs are made specifically for CIS, which in Germany, when a 3.2 short stroke was a popular upgrade, those P/Cs were not. I finally asked him the penultimate question, which was, "What is this upgrade good for?" His answer: "Torque and nothing more. You realize no top end horsepower gain."

More or less, what a gleaned from this phone conversation was A) It's a damn expensive upgrade; B) It works better with stock SC cams; C) It's for low to mid-range torque; D) 20/21 cams with the upgrade are a no-no; and E) Never call "Brand A" at 1:00 PM PST to talk this guy. He was really pissed that I interrupted his lunch.

[Doug Zielke]

"Never call "Brand A" at 1:00 PM PST to talk this guy. He was really pissed that I interrupted his lunch."

Thanks dd74, for interrupting his "lunch". Ef him, too. We can buy our parts from guys like Steve who treat customers with a modicum of decency.

As far as the 20/21 cams are concerned, they *are* intended for use with CIS.

While I have no doubt Brand A would charge you $8K for this worthless mod, they *won't* be getting it from me.

If anyone is interested what Bruce Anderson thinks of this mod, they can see his comments in the 911 Performance Handbook, Pg. 144.

[surflvr911sc]

I’m planning a rebuild next year and have been collecting ideas. When I was reading this thread I got really excited about doing this.

The more you guys research this, and thanks for doing all the leg work for us clueless people, the more I think I’m better off performance-dollar wise just going with 20/21 cams, 9.8:1 pistons and SSI exhaust.

What do guys think? Is a practical short-stroke 3.2 dead, or is the jury still out on this?

[dd74]

Is a practical short-stroke 3.2 dead? Nah. What's dead is the show "Diff'rent Strokes," which probably isn't an entirely bad thing.

One question I have is what constitutes a "practical" short stroke? Less compression? Less radical cams?

Thing is, before I asked the initial question about short stroking a 3.0 to 3.2, I searched for the process on the board but didn't see a whole lot. This is partly why I wondered about the process itself, and why, in accordance with, say, backdating an SC exhaust, the short-stroke scenario gets short shrift, if at all. It does seem that more have transplanted actual 3.2 engines into their cars than short stroked their three liters. At least that's what I surmise. I can tell you that from what I've seen on this board, ebay and Rennlist, a majority of 3.6 engines are considerably less expensive than short stroke set ups when you're a non DIY guy, which I am. But hell, 9.8:1 pistons and 20/21 cams constitute a probable tear down of an SC engine anyway, an exercise in and of itself that costs what? $6,000? $500 more starts to see 3.6 territory.

On the "blown" side of things, Supercharging of Knoxsville has two blower kits for the SC: 1) A Paxton and 2) an Autorotor, each unit costing $5,000 and $6,500 respectfully, though please don't quote me on those prices or the manufacturers' names for that matter. I read SOK's brochure a while ago, (can't find it now), and remember them saying somewhere that the Autorotor unit makes the 3.0 feel like a 6+ liter. Now that's torque even a 3.6 can't put out -- if it's all true, of course.

So in short (no pun intended), the 3.2 short stroke? Not dead, just not well known to this board user. As for "Diff'rent Strokes?" That is dead.

[surflvr911sc]

Well I am glad you cleared up the Different Strokes dilemma. I’m pretty happy about that.

Practical Short Stroke- I just mean is worth the extra cost to go though with it compared to the performance gain it would produce. I’m planning on doing the rebuild myself. I’m thinking ballpark $5000+, including new pistons, 20/21 cams, and SSI exhaust. I’m not seeing the advantage of spending an extra $2000 to short stroke other than a little “cool” factor. I do think it would be neat but would it be worth it. I know, one man’s worth…
Considering the unknowns and anything I may not have thought of I wouldn’t be surprised to spend the extra $2000 anyway.

[Lawson]

Slightly off topic but I just had a 3.2 put in my 78sc. The motor has PMO's, 10.5:1 JE's, Pauter rods, electromotive and will be soon have RSR headers and Phase 9 silencers. Took it up to Watkins Glen for a DE event a couple of weeks ago and had big fun surprising some of the 993's and 3.2's etc.!

[emcon5]

Another thing to consider, Bill V brought this up in another thread, is fuel requirements. Bill mentioned a built 3.2 that would go lean at high RPM's, and the fix was a replacement Fuel Dist. I don't know if it was a Carerra3 or late Euro SC FD, but both should work, I think. More displacement+higher compression+ more agressive cam= needs more fuel.

Details here, with commentary by Steve Weiner.

Tom

[dd74]

Never heard of them. What do they look like? Where can I find more information?

Thanks.

[Lawson]

I believe they are made by Jerry Woods Enterprises. Supposed to be louder than a muffler but quiet enough for most tracks. I think Bruce Anderson mentions them in his book when testing motors with different exhaust systems.

[dd74]

...or another way to contact him? Website, maybe? I'd like to see more of what he/they does/do.

Thanks.

[TimT]

beside being available from jerry Woods ( who makes them) phase 9 mufflers are available from Smart Racing as well

[emcon5]

Originally posted by dd74
...or another way to contact him? Website, maybe?

I think his number is in Bruce Anderson's book, if not, do a google search for "jerry woods porsche". He is probably listed on several PCA and racing pages.

Tom

[dd74]

Called Jerry Woods after a google search (which, BTW, worked great). The Phase 9 mufflers are part of an entire exhaust package that retails for $3,500. That includes special headers, non heat of course. Phase 9 mufflers will not hook up to SSIs or stock pre '75 heat exchangers. They're made exclusively for these headers.

Pretty pricey IMHO.

[carson911s]

Thought I would revive this old thread.

My old 2.7 came out yesterday.

The new 3.2 SS just went in today courtesy of Mike Jacobson at Spyder Automobiles just out of Melbourne. As usual, great service and a great bloke.

Standard CIS but SSI's and Dansk. All new rings, bearing etc so will be nice and fresh.

I am hoping it will be a big difference. I'll let you know when I get my baby back later this week after all the plumbing has been connected and Mike has put a couple of hundred kilometres on her to get her settled in.

I'm hoping for circa 230 bhp (?)

The new engine

The new engine.

The old one being dropped