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Bpickettx
02-23-2005, 04:57 PM
I’ve done a lot of research on both models 944 and 944S, here’s what I found out;

944
Best engine builder in the country is Jon Milledge, he claims about 180hp, costs can be upwards of 10K. According to him, scca has the car too heavy (what else is new!) based on his calculations, he raced the ARRC years ago and was pulled by top SpeedSource (Sylvain Trembly) car on straights. Most of the hp gains made are in the head work he does. The engines come balanced, almost no gains by burning new chip.

944S
Exact same motor except for head. According to Milledge, this head is designed really well so you wont get the kind of gains in a 2v car. His rebuild S motor puts out 200-205 hp max. Draw backs to the 944S and why the potential is not the same as say a comparable ITS car like 4 valve BMW e36 are the following: The ECU doesn’t offer any major gains, not as programable older system, second, the cams can not be re-indexed because the timing belt goes to one cam only (exhaust) then a chain from the middle of the exhaust cam connects to the intake cam. (sprocket is welded to the cam). As in a BMW e36 they have a Vanos cam adjusting system and you can play with the cam timing by re-indexing each cam.

With the increased weight of an S, and the same brakes (944 and 944S use exact same caliper and rotor) there’s not much of a difference when you calculate power to weight.

Have spoken to 5 guys around the country who run 944S, (2 of the 5 what I consider maxed out to the IT rules) same response everytime: good car, fast but no broken track records, and pulled by e36’s on straights. Since they’ve been let into the class (944S) 3 years ago, I haven’t heard of any winning races and none show up at the ARRC.

Other comments???

B Pickett

RR
02-23-2005, 07:07 PM
test

RR
02-23-2005, 07:35 PM
Dear Pickett, I used to run in the NE, had a 944 with a Milledge motor. I won a lot of races, but this was before serious competition came to town(now the ITS guys run rings around my old lap times)!! I can agree with you on the ECU stuff, I trailered my car 8 hours to a special chip/dyno guy in PA, to gain a whopping 5hp for $450 bucks!! I've heard good things about the S, but not many wins. I just love the cars, i believe in proper trim they are competitve maybe not ARRC winners, but contenders. The cam stuff you mentioned I guess is true although I never attempted to change the cam timing. My concern with the S is the weight, 2850 is heavy. I had an e36 ITS car last year which is the same weight, and braking was really good, the power was fantastic. Comparing the e36 with the 944s, 944 brakes are a little smaller, and early 80's ECU technology..its going to be a challenge.

There is a guy up here Kip Van-something, heard he built an S. Will keep you posted how he does.

Russ J.

timo944
02-24-2005, 04:44 AM
Thanks for this post. I have been debating getting an S to replace my aging 944, but I think after hearing comments here and elsewhere it's a waste of money.

I notice that moving 944 to ITA got nixed again, so maybe they'll lower the weight again to make it more competitive. I've had a hell of a time getting it to 2715 and keeping it raceable for PCA a the same time though.

wpspeedracer
02-24-2005, 08:10 AM
I've devoted two years in running an S and all things considered....I have no regrets.
Here's how I look at it>
If you want to win..you are going to spend $$$ in anything...A top class RX-7 or a 325 is $30 k + to have a front running car..and I've seen 325's run in to the 40's.
As far as driveability, handling, and realibility it's hard to go wrong with a 944 . N/A or S...they are just so much fun to drive, and forgiving.
Secondly, with over 200,000 produced...E-bay is a great source for replacement parts which helps in overall maintanance.

Venu: with a 944, there are so many race venue's you can compete in that gets you onto any track - anywhere - with similar competition if you class your car right. Set it up for ITS at 2750 #'s with out your interior...then save all interior parts to go in easily for PBOC and PCA, you add about 75#'s in weight and now you are set for PCA at 2822#'s
Ive also started getting into longer races where the realiability of the 944 comes into play big....3 hour + enduro's. You can go over 2 hours on a tank of gas ( less pit stops ) your brakes never go away and can last a 12 hour, tire wear is even due to the weight distrubutition, etc. so as the race goes on, you slowly climb up teh ladder as everyone else droops out.

As far as times and performance, I think I have squeezed out as much hp as you can get without spending lots of $$$$. Good motor and head, good suspension, and good exhaust system has me 1 - 2 seconds /lap behind on short tracks ( Roebling 1:21 > 1:23 ) and 4 - 5 seconds off on long tracks ( Sebring 2:32 > 2:37 ) which i attribute a couple of seconds to driving ability alone because I have been going up against a driver, Kyle Rathbun, who is driving a stock - full interior - stock suspension - still has stock exhaust with the cat still on 87' 944 S and we are only a second apart because he just flat outdrives me....he's really shown me how good a 'good' driver really drives.

All in all, I am usually in the top ten in ITS and can be very competitive ( 1st - 3rd ) in PCA H class and PBOC R-7. I get the same prize money as the winning ITS guys at half the price and just as much fun.

Mark
#54 ITS

GKR_17
02-24-2005, 08:43 AM
Originally posted by Bpickettx:
As in a BMW e36 they have a Vanos cam adjusting system and you can play with the cam timing by re-indexing each cam.


That is possible with the BMW, but not legal.

As for the 944S, I don't think we've seen even a glimpse of its capability. Those complaining about the computer surely haven't tried MOTEC, which unfortunatly is getting more common. Don't forget that the E36 was out for over 5 years before it won at the ARRC.

Grafton

Geo
02-24-2005, 09:30 AM
Quite right. Reindexing the cams is absolutely illegal so the lack of ability to do so it a red herring.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

924Guy
02-24-2005, 10:16 AM
Geo and I've already talked about this, but I'm curious to see what other 44 guys are running on the suspension side - anyone feel willing to throw out some numbers/info? Spring rates, bars, dampers? I'm in ITB, don't even have to worry, so I'll throw it out there; started out (last 4 years) with a fairly normal 400#/30mm setup, but seems soft (judging by tire wear vs. temps). So I'm going stiffer now; turning it to 11! I've got 660# front springs (leftover from some other 924 Prod car), and am planning on 34mm rear bars to keep the balance. Still running stock 924 front bar (22mm I think?), with the 19mm adjustable rear cup car bar. 400/30 was balanced, and 660/34mm will be 65% stiffer and still balanced. Shocks will continue to be the Bilsteins, revalved.

So, anyone else car to share setup?

------------------
Vaughan Scott
Detroit Region #280052
'79 924 #77 ITB/GTS1
www.vaughanscott.com

RR
02-24-2005, 11:52 AM
To answer questions regarding cam indexing. GCR clearly states in the rules, you can re-key or index cam shaft to compensate for milling head, its legal.

Second ECU. Im not sure what you mean by Motec, are you saying replace the ECU. According to GCR rules you cant replace the computer only alter it. I went through this with my 944, I didnt just go buy an off the shelf chip. I went to a custom chip maker, Milledge referred me to the guy. Let me say we spent hours on the dyno, interfaced with electronics measuring everything. Made 5 or 6 chips, I got 5 lousy HP. Trust me when I say, there is nothing to be gained here.

I really love these cars, and would/will build another one given the chance. I'm a walking manual when it comes to these cars, and know what they are capable of and not. Jon Millege Engineering in my opinion is the national expert, every one else either cheats or lies, and when he states gross hp one believe it.

Bpickettx
02-24-2005, 12:57 PM
Is it Kip Van Steenberg, who built a 944S in your area? I dont know if his car will be a good representation of a legal ITS car. He has built 2 ITS cars one a black e36 that smoked everything in sight. Heard the car was caught for something, then sold and vanished. Other car was a RX7, ran in Northeast, broke all trake records, sold to local guy, now mysteriously much slower in hands of new owner.

The plot thickens.

RR
02-24-2005, 10:09 PM
Vaughn Scott, where did you find rear torsion bars over 30mm. Paragon and weltmeister carry up to 30?

GKR_17
02-24-2005, 10:12 PM
Originally posted by bmw#29:
To answer questions regarding cam indexing. GCR clearly states in the rules, you can re-key or index cam shaft to compensate for milling head, its legal.


If by compensate, you mean bring back to factory specs, then you are correct.

Cars with adjustable cam gears, like the E36, MUST be set at factory specs.

Reread the ECU rule, then read the threads on Motec on this site. You're way off on the computer rule.

Grafton

Geo
02-24-2005, 10:13 PM
Originally posted by bmw#29:
To answer questions regarding cam indexing. GCR clearly states in the rules, you can re-key or index cam shaft to compensate for milling head, its legal.

Ah yes, but what you fail to mention is that is specifically mentions you can use an offset key on the the crankshaft only to return the cam timing to stock (italics mine). It's still possible to return the 944S cams to stock timing as I understand it. Using an offset key to reindex to other settings would not be legal as the rule is currently written. http://ITForum.ImprovedTouring.com/smile.gif


Originally posted by bmw#29:
Second ECU. Im not sure what you mean by Motec, are you saying replace the ECU.


This is not quite right. You may replace the guts of the ECU as long as you use a stock ECU housing and stock connector. People are already using MoTeC ECUs installed inside the stock ECU housing and wired internally to the stock connector.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

Geo
02-24-2005, 10:16 PM
Originally posted by bmw#29:
Vaughn Scott, where did you find rear torsion bars over 30mm. Paragon and weltmeister carry up to 30?

I bought mine from Paragon. Jason sells them for the same price as the hollow Weltmeisters. Probably higher quality too.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

RR
02-24-2005, 10:28 PM
Sorry guys, my bad on the ECU rule. Didnt realize you can gut it,thought it was just new chip. will consult GCR. dont know anything about motec, but know its expensive. since scca is looking out for the underfunded, wife watching my bank account, why make a rule change that can cost bid dollars?

timo944
02-25-2005, 03:18 AM
Suspension: I am still using the 28mm bars, but with 550lb springs. Not the ideal setup but I have other priorities.

Has anybody tried the Advance Design shocks? I bought some for $1600 last year, and I like them. The comparison basis is worn out Koni's tho, so would like to hear other opinons

Mark - Kyle is a hell of a driver. We paddocked w/ him at the Daytona event last year - great guy. That car is bone stock!

Geo
02-25-2005, 08:28 AM
Originally posted by timo944:
Has anybody tried the Advance Design shocks? I bought some for $1600 last year, and I like them. The comparison basis is worn out Koni's tho, so would like to hear other opinons

I'd like to hear opinions as well. I am getting close to having to commit to my damper set-up and I've been debating the ADs and Koni 8611/8212 DA twin tubes. They are pretty much the same price. The trade-off is the ADs are gas and Koni's vast experience.


------------------
George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com

924Guy
02-25-2005, 10:22 AM
Correct, Jason can special-order the 34's. Reminds me (since I haven't ordered them yet) that I do need to call him and get that order going...

Timo - you're racing a 944 in ITS and you've other priorities than your suspension? Well, I hope those priorities are more fundamental (like build or safety), not power. OTOH, give it a year and we may have some improvements on suspension tuning for you to benefit from (not just the same crap everybody buys because it's what everybody else is running, suspension tuning by the lemming principle). IMHO, Bilsteins are hella bang for the buck if you can take the leap of faith to step away from the adjustables.

------------------
Vaughan Scott
Detroit Region #280052
'79 924 #77 ITB/GTS1
www.vaughanscott.com

Andy Bettencourt
02-25-2005, 11:49 AM
Originally posted by Bpickettx:
Is it Kip Van Steenberg, who built a 944S in your area? I dont know if his car will be a good representation of a legal ITS car. He has built 2 ITS cars one a black e36 that smoked everything in sight. Heard the car was caught for something, then sold and vanished. Other car was a RX7, ran in Northeast, broke all trake records, sold to local guy, now mysteriously much slower in hands of new owner.

The plot thickens.



Easy. Unless you know, don't post stuff like this.

We ran against Kip in his E36 and his RX-7. He only owns ONE track record in the NE, we own the rest http://ITForum.ImprovedTouring.com/smile.gif

The BMW was REAL fast AND maxed out. It was taken to the ARRC and disqualified (along with the top Bimmerworld car) in 2002 for a bogus ballast placement issue. The engine was DEEMED legal.

Kip's 944S will be representative of a top car with a top driver.

Sheesh.

AB

------------------
Andy Bettencourt
New England Region, R188967
www.flatout-motorsports.com (http://www.flatout-motorsports.com)

wpspeedracer
02-25-2005, 05:38 PM
The best modification/best return I found was to get air in and out of that 16 valve head...and the car wakes up like you wouldn't believe....start with headers...then finish with the right exhaust muffler ..the muffler alone will add 7 lbs of tourque ....I tested 5 mufflers on a dyno and found the right one....and it wasn't at all what I expected...side in - center out Flowmaster.
mark

[This message has been edited by wpspeedracer (edited February 27, 2005).]

seckerich
02-25-2005, 06:24 PM
I have also raced Kip in the BMW as well as the RX7. Kip is a good driver and is willing to spend the time and money to develop a car to the max. I would hold off on the "cheater" terms with no proof.
Steve Eckerich
ITS Speedsource RX7

Originally posted by Bpickettx:
Is it Kip Van Steenberg, who built a 944S in your area? I dont know if his car will be a good representation of a legal ITS car. He has built 2 ITS cars one a black e36 that smoked everything in sight. Heard the car was caught for something, then sold and vanished. Other car was a RX7, ran in Northeast, broke all trake records, sold to local guy, now mysteriously much slower in hands of new owner.

The plot thickens.

lateapex911
02-25-2005, 09:31 PM
Yea....fact setting time...car DQ'ed at the ARRCs for a ballast infraction. It was 12 " or so from where it should be. Is that what made it so fast???

Then he sold it and it vanished? Maybe it was sold to a club guy? Maybe it was wrecked testing? Who knows?

A car slower post sale? Like that's never happened? The guy who bought mycar never gor it within two seconds of my time at Lime Rock, and I set that time the 3rd trip to the track...and those who race with me can tell you I'm no Kip VanSteenberg!

So, I'd be careful with what I implied...

On the other hand, Andy...was the entire engine torn down? Or jsut the standard ARRC teardown? if it's the latter, it just proved that the engine didn't have certain work done, but it isn't proof of legality either...


------------------
Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]

timo944
02-28-2005, 08:03 AM
Another advantage with the Advance designs - they are very light.

Vaughan - Safety - I am putting a new cage in. I agree w/ you about the lemming problem. And I'm guilty. I spent untold $$$ on Kokeln sway bars and they are a pain to set up with no advantage, other than the factory bars have rubber bushings in the a-arms that I don;t like. I'd liek to hear what you have to say about suspension set up. So far I have played mostly with camber settings, and a little with toe. But it's all a moot point until I get new torsion bars. I was planning on 30mm rate hollow bars (which I think measure 32-33mm), no more. I can't see going higher than that and don't want to buy them to find they are too stiff and them have to ebay them afterwards. Any comments?

timo

924Guy
02-28-2005, 09:20 AM
Sure - I think you'll find that the 30mm are still soft; that's what I've found on my car, and I run right at 2620lbs (min spec weight plus room for error). I suspect you'd be better off with at least 32mm. This, combined with your monster swaybars, might well be a decent starting point. Then it's matching up the shocks to the suspension; in my case accomplished by shipping them in and having them redone. But you're going go with the AD's? Is there any statement out there what range of suspension they can deal with/are valved for? I'd hate to buy a shock and find out after the fact that I'm out of the range of adjustment...

------------------
Vaughan Scott
Detroit Region #280052
'79 924 #77 ITB/GTS1
www.vaughanscott.com

Blix
02-28-2005, 12:00 PM
On the Kip Van Steenburg thing...

Kip also has, in the past, had a VERY nice and VERY complete Data Acquisition system in the car, that he knows how to use VERY well. He has been nice enough to sit down and show me what he does, and why, on a couple of occasions, just because I've asked. I would add that to reasons that he and his car are fast. He knows exactly what is going on with the car, and his driving, and can make very positive changes every time he gets in.

Tom Donnelly
02-28-2005, 03:08 PM
Kip's car was legal. From what I had heard, it was originally owned by Dino Steiner and run by him and Ian James in IT and GrandAm as a dual purpose car. The car hasn't vanished, its just been repainted by the new owner. And its still fast and legal.

Tom

timo944
02-28-2005, 03:34 PM
Vaughan - I already have the AD's. They are valved for 600lb. front and back, but can be revalved by the customer. Far as I know there's no maximum limit. They can also be serviced by the customer.

32mm bars - sounds pretty big but then ya gotta keep up with the Joneses

About Dino Steiner - that is one fast car. I think he got protested by Tremblay so many times he quit IT. Was the car legal? he never got busted as far as I know...

timo944
02-28-2005, 10:13 PM
More thoughts about torsion bars and springs:

My understanding, you pick front springs to get a good balance between suspension frequency and braking. I started with 400# and upped it to 550# in order to reduce the dive under braking. It's pretty much gone. According to calculations I picked up in a race car design book, the suspension frequency is around 165Hz. The book recommends a suspension frequency of b/w 120 and 150, but it's an old book, probably printed before the age of high-tech shocks.

Rear: The rear should be high enough to prevent the rear of the car drooping under power. The 944 has low power, so less need to have a high spring rate. So i figure pick a value to match the front. According to the book i have, the suspension frequency needs to be 2-3% off the front, higher or lower doesn't matter. If I calculate suspension frequency for a 34mm bar, it works out to 146 Hz.

These numbers vary according to the front/rear weight distribution and the unsprung weight.

I assumed 700 lbs at each corner (w/ driver), and unsprung weight of 100 lbs on each corner in the front and 70 lbs in the rear.

So it looks like a 550#/34mm set up would be right on the money.

timo

924Guy
03-02-2005, 12:55 PM
Pretty much agrees with my estimations for balance (keeping in mind that I have a relatively soft front bar, requiring just a bit more front spring to keep the car from getting too tail-happy). Always found the car indecently stable in heavy braking, which, coupled with the indestructible brakes, allows for LOTS of passing in the braking zones. Only way to pass much on track with 115hp! http://ITForum.ImprovedTouring.com/smile.gif

Another pleasant surprise was to talk with the guy at Bilstein Motorsport about valving; he recommended I stick with what I have to start with, and only make changes as I feel a need to tune. It's apparently all within the realm of tuneability at this point, one setup vs. the other. I'm really happy about this now, as I'll probably run my first weekend with the same (current) setup, to get a good baseline before switching over.

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Vaughan Scott
Detroit Region #280052
'79 924 #77 ITB/GTS1
www.vaughanscott.com