Fastest 993 N/A version for AutoX?
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Leeds wrote:
"The Boxster S is a much better car for autocross, with less weight, better balance and handling, better gearing and not that much less power now."
NOT great feedback Leeds (for those of us with 993's) :-)
Can you share any setup info from your 993 experience? I remember Stacy and Greg running up front at National's in 1995-96.
James:
I believe you will find that those running Boxsters (Rob F, GH, etc.) will recommend that you have PSM.
I personally believe the Boxster S is the way to go, but sometimes passion pulls you in a different direction.
Regarding the RS front swaybar, does it have adjustable settings both stiffer and softer than the M030 bar? If not softer, won't it just promote more understeer?
"The Boxster S is a much better car for autocross, with less weight, better balance and handling, better gearing and not that much less power now."
NOT great feedback Leeds (for those of us with 993's) :-)
Can you share any setup info from your 993 experience? I remember Stacy and Greg running up front at National's in 1995-96.
James:
I believe you will find that those running Boxsters (Rob F, GH, etc.) will recommend that you have PSM.
I personally believe the Boxster S is the way to go, but sometimes passion pulls you in a different direction.
Regarding the RS front swaybar, does it have adjustable settings both stiffer and softer than the M030 bar? If not softer, won't it just promote more understeer?
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The RS-swaybars for a 993 are both adjustable. 5 settings in front and 3 in the rear.
I have mine on the middle in the front and on the firm setting in the rear. I am currently running 205/255 tire sizes (MPSC). With these settings (and the PSS-9's on firm) it's a whole different car than stock. Still a little understeer on corbner entry and a little oversteer on the exit, but I like the way it handles now much more than stock.
I have mine on the middle in the front and on the firm setting in the rear. I am currently running 205/255 tire sizes (MPSC). With these settings (and the PSS-9's on firm) it's a whole different car than stock. Still a little understeer on corbner entry and a little oversteer on the exit, but I like the way it handles now much more than stock.
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Originally posted by James Gunn
Great feedback Leeds.
You can get the Boxster S without PSM. Is it better to go without PSM?
James Gunn-Wilkinson
Great feedback Leeds.
You can get the Boxster S without PSM. Is it better to go without PSM?
James Gunn-Wilkinson
Not perfect but better than having lots of wheelspin.
I've noticed no negative impact of PSM (when off) in the Boxster S unless you spin wildly out of control (and press the brake).
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I had the 993 a while ago (94-97) so my memory may not be the best. I ran negative 1.5 degrees camber in front and negative 1.7 degrees in the rear with slight toe out in front and the minimum of the factory range in the rear. Four wheel cars were negative 1.7 front and rear. These camber settings are lower than in my 996 or what would be run with Hoosiers or Kumhos because the tires were BFG Comp T/A R1 back then and they were designed to run with less camber. Also these settings are from the end when the car was in ASP configuration.
It's quite important to get the kinematic setting correct in the rear suspension. When the 993 came out the factory tools to do this were $2400 for the set. There are alternative tools created for the 911RSR race cars of the period and I think they were about $400. I don't know how this is handled now. Basically the original tools compare the relative angles of two of the rear suspension links and I think the race tool measured the front to rear tilt of the rear upright (bearing carrier).
Val Korry ran his yellow '95 993 C2 in SCCA stock configuration in the late '90s and I think used Konis in front to help correct the push. I will talk to Val and Greg next week. Val still has this car but it is highly modified for road racing. He ran it in Street Mod 2 at Nationals this year and is now playing with a GT3.
As was mentioned above PSM includes ABD that prevents one rear wheel from spinning using the rear brakes. ABD does not prevent both rear tires from spinning. It is also still functional with the PSM switched off. PSM does reengage while braking which interferes with turn-in. You need the ABD and you can't get it alone.
ABD in the Boxster is can be slightly disruptive when it engages, but this isn't a problem in the 993 and 1999 996. Both of these cars included ABD with the limited slip and ABD engaging with the limited slip seemed smoother than with an open dif as in the Boxster.
My 2003 Boxster has an adjustable front sway bar, 245/35-18 Hoosier Autocross compound tires front and rear and negative 0.8 degrees camber in front, negative 1.5 degrees in rear. Maybe using this same technique on the 993 would help with the balance.
It's quite important to get the kinematic setting correct in the rear suspension. When the 993 came out the factory tools to do this were $2400 for the set. There are alternative tools created for the 911RSR race cars of the period and I think they were about $400. I don't know how this is handled now. Basically the original tools compare the relative angles of two of the rear suspension links and I think the race tool measured the front to rear tilt of the rear upright (bearing carrier).
Val Korry ran his yellow '95 993 C2 in SCCA stock configuration in the late '90s and I think used Konis in front to help correct the push. I will talk to Val and Greg next week. Val still has this car but it is highly modified for road racing. He ran it in Street Mod 2 at Nationals this year and is now playing with a GT3.
As was mentioned above PSM includes ABD that prevents one rear wheel from spinning using the rear brakes. ABD does not prevent both rear tires from spinning. It is also still functional with the PSM switched off. PSM does reengage while braking which interferes with turn-in. You need the ABD and you can't get it alone.
ABD in the Boxster is can be slightly disruptive when it engages, but this isn't a problem in the 993 and 1999 996. Both of these cars included ABD with the limited slip and ABD engaging with the limited slip seemed smoother than with an open dif as in the Boxster.
My 2003 Boxster has an adjustable front sway bar, 245/35-18 Hoosier Autocross compound tires front and rear and negative 0.8 degrees camber in front, negative 1.5 degrees in rear. Maybe using this same technique on the 993 would help with the balance.
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OK - time to jump in too.
I've been working to get my 993 to be competitive in Ni. And while that is different than A stock i think many things can be shared:
Suspension Work:
- 18" hollow spoke technology wheels
- 225/40/18 front and 285/30/18 rear with Michellin pilot sport cups (i just switched from the kumho ecsta v700 and made my rear wider)
- RS sway bars set to 2nd tightest up front with tightest on rear
- Koni adjustable front shocks
- H&R lowering springs
- Koni double adjustable rear shocks custom built and matched to my springs (these were a custom order directly from koni)
- front upper stress bar
- i'm running -2.5 degrees of camber in front and -3 degrees of camber in rear (i really would like people's opinion if this is the way to go?)
I think you can do all that I did (except for the new springs) and stay in A stock - but i'm not sure.
I've made a series of performance mods to enhacne h.p. but those are fairly minor. Most of the work was on the handling of the car.
I'd really like to hear feedback on my setup....
Cheers,
Boris
I've been working to get my 993 to be competitive in Ni. And while that is different than A stock i think many things can be shared:
Suspension Work:
- 18" hollow spoke technology wheels
- 225/40/18 front and 285/30/18 rear with Michellin pilot sport cups (i just switched from the kumho ecsta v700 and made my rear wider)
- RS sway bars set to 2nd tightest up front with tightest on rear
- Koni adjustable front shocks
- H&R lowering springs
- Koni double adjustable rear shocks custom built and matched to my springs (these were a custom order directly from koni)
- front upper stress bar
- i'm running -2.5 degrees of camber in front and -3 degrees of camber in rear (i really would like people's opinion if this is the way to go?)
I think you can do all that I did (except for the new springs) and stay in A stock - but i'm not sure.
I've made a series of performance mods to enhacne h.p. but those are fairly minor. Most of the work was on the handling of the car.
I'd really like to hear feedback on my setup....
Cheers,
Boris
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I took the weight of my 2001 Boxster S two weeks ago.
2001 Boxster S, Hi-Fi, PSM, Xenons, 6-speed, 18x7.5" and 18x9" 2003 Carrera wheels on Hoosiers 245/35R18 all around.
- No spare tire.
- No tool kit.
- 1/8th gas tank.
- No mats.
- No windscreen
2936 lbs and 3124 w/driver (guess my weight?).
a 993 C2 6-speed is around 3060 lbs. I guess my car's weight is close to 3000 lbs with the stock wheels (18" sport Design and PZeros).
The weight is similar in the Boxster S and the 993 C2.
In my opinion a 993 C2 could be a bit faster than a Boxster S on pro hands in auto-x. I have seen a 96 C4S which is 111 lbs heavier than the C2, with stock suspension (no M030) on 245/275 Hossiers beat my times consistently in auto-x.
I don't know the specs on the 98 C2S which is heavier due to Turbo body and Turbo heavy brakes, but at the same time is fitted with wider wheels, wider rear fenders and it has stock lowered stiffer springs.
The 96+ has plenty of torque at low rpm, something doesn't exists in the Boxster S due to the 4 cams and 24 valves and a 3.2. At midrange rpm the 96+ 993 is even better.
2001 Boxster S, Hi-Fi, PSM, Xenons, 6-speed, 18x7.5" and 18x9" 2003 Carrera wheels on Hoosiers 245/35R18 all around.
- No spare tire.
- No tool kit.
- 1/8th gas tank.
- No mats.
- No windscreen
2936 lbs and 3124 w/driver (guess my weight?).
a 993 C2 6-speed is around 3060 lbs. I guess my car's weight is close to 3000 lbs with the stock wheels (18" sport Design and PZeros).
The weight is similar in the Boxster S and the 993 C2.
In my opinion a 993 C2 could be a bit faster than a Boxster S on pro hands in auto-x. I have seen a 96 C4S which is 111 lbs heavier than the C2, with stock suspension (no M030) on 245/275 Hossiers beat my times consistently in auto-x.
I don't know the specs on the 98 C2S which is heavier due to Turbo body and Turbo heavy brakes, but at the same time is fitted with wider wheels, wider rear fenders and it has stock lowered stiffer springs.
The 96+ has plenty of torque at low rpm, something doesn't exists in the Boxster S due to the 4 cams and 24 valves and a 3.2. At midrange rpm the 96+ 993 is even better.
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OK,
PSM is the way to go on the Boxster S it seems.
Back to that 993... The RS bar is 23mm which is 1mm larger than the stock M030 front bar, but it has 5 settings and I am sure the 2 softest are as soft and softer than stock if that is needed. Paul, if this works, you owe me one:-)
I think I may just have to try the 993. I certainly like the looks and motor more than the Boxster S, although the 2003 Boxster S is not too bad looking and I am sure it is faster on most courses... Decisions, decisions
James
PSM is the way to go on the Boxster S it seems.
Back to that 993... The RS bar is 23mm which is 1mm larger than the stock M030 front bar, but it has 5 settings and I am sure the 2 softest are as soft and softer than stock if that is needed. Paul, if this works, you owe me one:-)
I think I may just have to try the 993. I certainly like the looks and motor more than the Boxster S, although the 2003 Boxster S is not too bad looking and I am sure it is faster on most courses... Decisions, decisions
James
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the two issues that come to mind with autox the 993 are corner exit understeer, and gear ratios.
I have been fighting the exit understeer, but have minimized it to a point where going to 225's is the next step. I have been on the same tires all year to get a repeatable comparison to suspension and sway bar changes. The RS rear bar and more camber have helped. Been all over the place with tire pressures, and have concluded a larger front tire is the next step.
The gear ratios are terrible for autox! 1st gear is way too low, 2nd is not low enough, at least for the local PCA events I have been running. I can never get the revs where the engine is making good power. Very frustrating.
I have been fighting the exit understeer, but have minimized it to a point where going to 225's is the next step. I have been on the same tires all year to get a repeatable comparison to suspension and sway bar changes. The RS rear bar and more camber have helped. Been all over the place with tire pressures, and have concluded a larger front tire is the next step.
The gear ratios are terrible for autox! 1st gear is way too low, 2nd is not low enough, at least for the local PCA events I have been running. I can never get the revs where the engine is making good power. Very frustrating.
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Some have mentioned here about using PSS9s & RS Sway bars. Regarding this thread, won't these "mods" bump a 993 straight into ASP (A Street Prepared)? I'm sure that Bilstein HDs would keep the car in A Stock, but I'm not so convinced about the PSS9s & RS sway bars. Can anyone confirm?
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PSS9's would be OK if you could adapt them to run with the M030 springs and set them at a ride height within the US factory spec. The mounting method would also have to be the same as stock.
Rear sway bar changes are a no go in Stock. You could change to the M030 sway bar in the rear. The front sway bar is pretty much open.
James
Rear sway bar changes are a no go in Stock. You could change to the M030 sway bar in the rear. The front sway bar is pretty much open.
James
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I have some more questions:
1. Is there any difference in transmission or final drive ratios on any of the 993 years? Models (C2, C4, C2S, or C4S)?
2. Is there any difference in size between the M030 rear sway bars on any of the 993 years? Models (C2, C4, C2S, or C4S)?
3. Is there any difference in the wheel sizes (width or offsets) on any of the 993 years? Models (C2, C4, C2S, or C4S)?
4. Front and rear track differences on any of the 993 years? Models (C2, C4, C2S, or C4S)?
There may be some magical site with all this info, if anyone knows, let me know.
James
1. Is there any difference in transmission or final drive ratios on any of the 993 years? Models (C2, C4, C2S, or C4S)?
2. Is there any difference in size between the M030 rear sway bars on any of the 993 years? Models (C2, C4, C2S, or C4S)?
3. Is there any difference in the wheel sizes (width or offsets) on any of the 993 years? Models (C2, C4, C2S, or C4S)?
4. Front and rear track differences on any of the 993 years? Models (C2, C4, C2S, or C4S)?
There may be some magical site with all this info, if anyone knows, let me know.
James
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Hey guys,
Leeds:
Thanks for the info. Looking forward to hearing what Greg and Val remember about their 993 days in SCCA Stock class.
James and Boris:
Sounds like the front RS bar may be the hot ticket (if it has settings softer than the stock front bar) to help dial out the understeer. Any suggstions on where's the best place to find one? I've heard the same as Chris, that the 993's biggest drawbacks are understeer and gear ratios. Hey, I'll owe all you guys one for sharing your time and expertise.
Boris:
I'm real interested in hearing about your rear Koni's. Evidently they don't make the rears anymore. Did you have regular Sports and return them for the mods? Did you also have them de-gassed? I've always been partial to Koni's, but also understand Bilstein makes a good shock. Perhaps it is worth the time/$$ to try to modify the PSS9's, as the adjustability would seem to be necessary for the 993 as compared to the non-adjustable HD's.
Cgomez & NJ-GT:
Looking forward to meeting and running with you guys locally next year. Lynne and I will definitely need to get out early in the season as we've got a lot to learn about driving this "butt heavy" car.
Paul
Leeds:
Thanks for the info. Looking forward to hearing what Greg and Val remember about their 993 days in SCCA Stock class.
James and Boris:
Sounds like the front RS bar may be the hot ticket (if it has settings softer than the stock front bar) to help dial out the understeer. Any suggstions on where's the best place to find one? I've heard the same as Chris, that the 993's biggest drawbacks are understeer and gear ratios. Hey, I'll owe all you guys one for sharing your time and expertise.
Boris:
I'm real interested in hearing about your rear Koni's. Evidently they don't make the rears anymore. Did you have regular Sports and return them for the mods? Did you also have them de-gassed? I've always been partial to Koni's, but also understand Bilstein makes a good shock. Perhaps it is worth the time/$$ to try to modify the PSS9's, as the adjustability would seem to be necessary for the 993 as compared to the non-adjustable HD's.
Cgomez & NJ-GT:
Looking forward to meeting and running with you guys locally next year. Lynne and I will definitely need to get out early in the season as we've got a lot to learn about driving this "butt heavy" car.
Paul