It took me awhile to find CMW, but they do exist. They still offer both their kits and billet killer heads. They have moved more towards Toyota Racing though for cash flow, but still carry Porsche stuff. Though Porsche is still listed first on their website. Weird, Jack, it never showed up my searches either when I was searching for them...someone on the other list months ago gave me the lead.

http://www.cmwmotorsports.com/


By the way Jack, thanks for all the opinions on the RS/RSR options. I would have responded on that thread but didn't want to keep self bumping it to the top.

thabaer - that's a different car. It'll be intereisting to see if PAG fares well with the expanded model lines. I'd rather have seen a smaller, lighter Boxster (with 250 hp).

OMG !! Their Stage III 4.2 liter conversion kit is $35K !! My 911 has 3.6 liters. Is there any way an extra 0.6 liters can be worth $35k? Am I totally missing something here?

Damn - wonder what all that includes...

That's almost as large as my crank!;) :D

Janus,

Four points relative to cost:
1. Oh my God that is a lot of money
2. You have now witnessed the fact that going fast costs lots of money
3. In perspective, how much would Porsche charge for a 3.8 engine new? I remeber that their 3.8 kit was like $12k wasn't it and you still had to find a competent Wrench to put it together.
4. 35k and with the right skill you could be king of the hill at most events for NA engines :) How much do you think some of the HP Junkies have in their engines?

The price is related to lack of competition and to the law of diminishing returns.

If you think about it the 911 motor is the smallblock Chevy of the Euro sportscar world. It's overall dimensions (bore center, bellhousing, engine mounts etc) haven't changed over the years. I would think that crankshaft size and deck height have more to do with max displacement than bore spacing. I had a 410" (6.7L) smallblock Ford based on a 351W block, they can be taken up to about 450" or so but it's not practical for racing because you need a huge stroke to do it. However that long stroke makes for a stump puller of a street motor. I'd like to see stroker setups for 911 engines for 4-4.5 liters or so, talk about drivability! I'd also like to see a watercooled 4 valve setup like the factory did on some of the racecars, I saw a set on ebay not to long ago, big $$$$. I'd think someone with a CNC mill and time on there hands could whittle these things out of billet like S&S does for bikes.

Hmmm I wonder if billet would be strong enough?

4.6 litre is biggest i have heard of:

Koro GT3 4.6 RM S:
http://www.koro.de/

480 N/A HP at 7.300 rpm...

Watercooled, of course.

You're kidding right? It's a lot stronger than cast and a lot more $$$$. S&S is making 117" V-twin motors with 4+" bores and up to a 5" :eek: stroke! Hmmm 5.8L 911 anyone? You'd most likely need longer cylinders, timing covers, chain etc. but it could be possible. ;)

HA !! Now yer talkin' !! Wayne, any chance you can get a manufacturer so you can carry these ? :D

But sort of seriously, my p-tech told me it was a PITA to get stroker cranks to work in 911 motors - something about lower red lines, deck height (?) and not smacking the cylinder heads with the pistons. I didn't understand but the gist was that it would set my wallet on fire and he was talking about a max of 3.4 (from my stock 3.0).

"4. 35k and with the right skill you could be king of the hill at most events for NA engines How much do you think some of the HP Junkies have in their engines?"

Yeah, I guess I just couldn't figure out why it would be cost effective. I guess if you are devoted to being N/A - like religiously devoted, then you gotta increase displacement. But otherwise a turbo conversion or supercharger has to provide more bang for the buck, right? I think it was on this BBS I once read "The only replacement for displacement is positive manifold pressure."

SmileWavy

Yeah and there's no replacement for BOOSTED displacement! :) It is true that a stroker generally reduces the redline. My full race 410 with billet steel crank and forged rods had a redline of 7000rpm with a 4" stroke. A standard 3.5" stroke with those components would have a redline above 8500rpm. In the V8 world they have special tall deck height blocks available for large displacement setups. On advantage for the 911 (assuming the crank could fit in the crankcase is that it is possible to make longer cylinders and related items although I've never heard of it being done. Another problem with big strokers is the rod ratio and agularity, to long a stroke puts tremendous side loading on the piston due to the rod angle unless you run a tall deck height block. But let's assume for a moment that some inventive person made 15mm longer cylinders, a custom crank and rods, custom pistons, longer chain boxes, longer return tubes and custom intake and exhaust. You could possibly run as much as a 100mm stroke with a 104mm bore an wind up with a 5L 911! Since the bore to stroke ratio is still relatively square this motor would have a relatively broad torque and power band but you'd need to port the cylinder heads just to keep up with the displacement. Then let's assume that you added twin turbos like some of the 700+HP 3.6's running around, you're now just shy of 1000hp in a 911. Practical? NO, but it is possible.

Billet "i's a lot stronger than cast..."

But I doubt that teh heads are cast -- are they? I would expect them to be forged. When a billet is chopped out of a lump of metal the gran lines are just cut off, creating stress risers. Moreover, forging - if done properly -- aligns the grain lines along the lines of stress the material will recieve. That assumes the engineer knows where they are and correctly designs the forging process. Not as good as growing bone, but it's the best our technology can do until we learn to mimic biological systems more closely.

Very Interesting staff......................

Once more we found our selfs in another chapter "What If" in the P comunity, recently on one of the national events that we atteded, I was trying to find out what ever happen to "All The Ford Focus" that were runing the circuit, for my surprise I was told that one of the factorys focus had some problems and the factory was doing nothing about it, the team on their own took upon their selfs to figure what the continues problem was with the cranckshaft, "Solution" Install a Honda Cranck that they machined, you guess it as soon as Ford found out they pull the plug.

Same for us if someone could "Mix and Match" a few parts together it could be great to have a 4.5 TT but once more we found ourselfs on that Lonely road.

Unless that one of you guys goes for it;) I know we have a lot of people here with a great deal of engineering background, put the combination together and you never know who will build it.;)

Randy, I agree that forged would be the strongest. But on the S&S V-twin motors they're getting over 100HP in street trim so about 50HP per cylinder. I have read that they can go a lot higher in HP than they could go with cast blocks, cylinders and heads. Given that guys like Juan are running over 600 RWHP using cast factory heads I'd have to assume a billet head would be safe at those levels.

And Juan you're right it would be a lonely road mainly because of supply and demand which is why it isn't very practical. But then again running a 911 drag car isn't practical either, if you think about it the shortest, cheapest way to the 8 second range is the traditional big V8 in a back-halved Mustang or Camaro. You are doing this more for the enjoyment and challenge than anything else and that's the point. There are plenty of engineering/machinist types out there that make custom parts to pull off what others consider to be impossible. Eight years ago when I was building a 410" track weapon I was told import tuner cars would be the future of drag racing, I laughed at the idea then but today I've been proven wrong. In many ways the rear engine/rear drive layout of the 911 is perfect for drag racing since most of the force is concentrated around the rear wheels, there is no need for a stiffened frame to the front like a front engine/rear drive setup and a lot of the problems with front engine cars don't exist on a rear engine car. Think about it, the fastest cars at the strip (TF dragsters) are rear engined. Look what happened to the "so-called" hemis those things run. Every part is custom fabricated right down to the solid block itself, the only thing they have in common with the original hemi is a few basic dimensions. It would be interesting to see how large of a stroker crank could fit in the case of a 911 and build around it, the only obstacle is cubic dollars. :)

It's going to take Porsche a lot of work to compete with BMWs v10 7spd M5 and MB E55 that puts out more rwhp then the 911 makes crank

Okay, utterly ignorant question (not unlike all of my other questions): If a Honda crank can be used as the seed for a Ford, are there any cranks that can be machined to fit in a 911? Wouldn't one need to first find a crank from another flat six?

BTW - Juan, the pictures, videos, and descriptions of your dragster project are freaking AWESOME. I get giddy whenever I see a new update. Your car is so far off the charts, it's amazing.

Woo Hoo !! Yeah !! Nothing exceeds like excess !!

JanusCole

It is my pleasure to share it with the world.

This is what you will see very very soon in the world of "Import Racing"


http://www.bobnorwood.com/Max-4%20Technical%20Summary.htm


Ok this is what needs to happen here, lets play "Bench racing" and see if we could build on "Paper" a 4.5liter engine, so I assume we could start with the 3.6 Platform, turbos,Intercooler,Cylinder head work, Piping, EFI, Intake manifold,headers,blow off valves, wastegates,rods,pistons we could do very easy,

We need a crank, heads, and way to stroke the thing from 3.6 to 4.5, any takers:)

Juan what are the bore and stroke dimensions of a 3.6? 104mm bore cylinders are already available. There is a company (can't rememeber the name) that will weld up an existing crank and then offset grind it for a longer stroke. Assuming a 104mm bore, you'd need a 88.5mm stroke for a 4.5L 911. I think a 3.6 is 100mm bore with 76.5mm stroke, you'd need to add 13mm to the outside of the rod journals and then offset grind down to the original diameter. New rods and custom pistons would need to be made especially because longer strokes increase compression if the original piston and piston to deck height are used. Another possibility would be to go with smaller rod journals like some V8 strokers but I'm not sure that's a good idea and probably just as much work.