mdnt08

Have you tried GroudControls site, they offer the different combos of coil over threaded collars kits for the 944.

mdnt08

There is a Hawaii Region of SCCA Solo here, that's all we got on the island of Oahu. The courses are short avg 40sec and do have hair pin turns due to the smaller lot than other scca folks have. We only max out 2nd gear, never get in 3rd.

PedalFaster

I was also going to recommend getting aftermarket pieces, if not necessarily Ground Control, since aftermarket shocks (and threaded shock bodies) are legal.

This is actually a gray area, though. Since the sleeves aren't technically part of the shocks, it's not unreasonable to assert that you must run the stock sleeves. Then again, I'm pretty sure we didn't on my old 968 (as we had Motons with threaded bodies).

You're seeing one of the downsides of running a 27-year-old car with a rare option package. Maybe watch eBay and the PCA classifieds?

edfishjr

Good news: I have two sets of stock sleeves, spring perches and lock rings on the way. Somewhat beat up with some thread damage, but I think they will be serviceable with a little work.

I've already got new perches and lock rings on order from Porsche, so I'll have some extra parts.

As for perfect legality, I was prepared to go with an aftermarket solution but I think it would have to do 2 things to be legal and protest proof: 1) not be significantly lighter, and 2) not provide any extra range of adjustment. I would have to make sure I knew what the stock range of adjustment was, especially how low it could go, by measuring a stock assy, and be prepared to prove with pictures and measurements that I was not exceeding it.

For instance, the sleeves in the kits that are sold to convert standard struts to adjustable coil-overs appear to be a bit thinner material, but I'm not sure. Also, they definitely use a different type of thread that doesn't require a separate spring perch and locking ring. Therefore, the assembly is clearly somewhat lighter and might offer additional lowering capability. They are also designed to use racing springs with square-ground ends. Not sure how I was going to adapt to the Porsche spring with unground ends and variable wire diameter.

The other solution I was contemplating came from George Beuselinck at 944Ecology. He was willing to temporarily "sell" me a sleeve off a set of M030 struts he had tucked away so that I could reverse engineer it and have a set machined from scratch. That was quite a generous offer from someone I've never met.

Thanks to everyone for their help and comments to date!

P.S. with an aftermarket strut like the Motons were(?), since the strut is a suspension link, not just a shock, I'd think you might have to prove both things as well: no weight (performance) advantage and no adjustability advantage.

PedalFaster

I'm pretty sure the weight consideration is a non-issue. 13.5 says:

Several paragraphs of restrictions follow. As you noted, suspension geometry changes as a result of the strut substitution are explicitly forbidden, but there's no mention of weight. Pretty much everyone serious runs aftermarket struts, and this is the first time I've heard anyone mention weight as a consideration for legality. I don't think it is.

edfishjr

Interesting, and it never occurred to me.

Given this, I could design a legal strut from carbon fiber and Ti and take big weight out of the front of any McStrut car. (At incredible expense, of course.)

Braymond

I have a 944S and I'm running in C Street. Having read the rules a few times now it appears to require that I install all the M030 components if I want to install any of them. As an option package, it specifically states that I must install the entire option package and not just part of it.

Are you installing the M030 spindles and brakes too?

Braymond

One more question.

I'm running autocross on BFG 225/45-15 on the original 15x7 phone dials too. I definitely have noticed that I could use some more traction in the rear in the turns, slaloms, and exiting tight corners. I don't have LSD :-(

You mention there is a source for modifying the original 15x7 phone dials to 15x8 for the rear. Who offers that service?

edfishjr

I was referred to this guy http://www.weldcraftwheels.com

He said his backlog was 8 weeks but would shrink to 2 or 3 later in the summer.

edfishjr

it is true that option conversions must be complete. My reading of the 89-91 PET indicates that only the turbo got different hubs and spidles with the M030. The base and S2 did not. Also, the base didnt get different calipers like the S2 and turbo got.

I havent researched the earlier S.

Edit: Per the PET, the '87 944S M030 spindle (951.341.655 (656).34) became the standard spindle on the '89 Base. So, it maybe makes sense that they wouldn't have needed a new M030 spindle for a slower, lighter, less powerful car.

I have no idea what the difference is between the '87 standard spindle and the M030 version. If the difference was negligible, or negative, in autocross terms your competitors might not care. For instance, if the M030 gives more camber, or is only slightly heavier for durability, etc.

burglar

Oh hey, Weldcraft did mine, so that might have been me.

http://strcarrera.blogspot.com/2015/...ls-part-2.html

edfishjr

I actually got the referral from someone else, but really cool to see your results.

Did you ever sell that car? I think it was on BAT at one time.

sjfehr

Wow. Just... wow. Speaking as an engineer, there so so many reasons NOT to do that no matter how good the welds.

edfishjr

I've been skeptical too, but many of his customers are road-racers and the products seem to hold up.

My experience with weld repairs cracking is that the new crack develops a slow leak first which is catchable early, rather than a catastrophic failure. It's happened to me twice.

If I were regularly tracking such wheels, I think I'd dye-penetrant inspect on a schedule.

burglar

Nope still have the car and the 9" front wheels.