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nolift914
Is my Autox 914 too stiff?
I am currently running the PO setup, the 914 was set up for club racing with front and rear coil overs. The front is at 330lbs/in which I believe is the equivalent to 25MM torsion bars and the rear is at 230. The 914 is a 4 weighting approx 1780lbs with bias ply slicks. I plan on switching to Dot-R radials. I have always thought for autox go soft on springs and big on bars. Does the paddock crowd have any suggestions for a setup. The autox sites in NYC tend to be on the rough side. I was thinking either 175 lbs/in in front and 140 lbs/in rear or 200 lbs/in front and 180 lbs/in rear.
Randal
QUOTE(nolift914 @ Sep 17 2013, 05:36 PM) *

Is my Autox 914 too stiff?
I am currently running the PO setup, the 914 was set up for club racing with front and rear coil overs. The front is at 330lbs/in which I believe is the equivalent to 25MM torsion bars and the rear is at 230. The 914 is a 4 weighting approx 1780lbs with bias ply slicks. I plan on switching to Dot-R radials. I have always thought for autox go soft on springs and big on bars. Does the paddock crowd have any suggestions for a setup. The autox sites in NYC tend to be on the rough side. I was thinking either 175 lbs/in in front and 140 lbs/in rear or 200 lbs/in front and 180 lbs/in rear.



Currently running 19mm torsion bars with a smart racing bar, with the smallest diameter bar they offered. Had under-steer until I went to the lightest smart racing bar. Front shocks are Koni's set to almost total soft. Rear springs are 240# if I remember correctly. They might be #225, but will check.

With Avon's no under-steer at autox's or hilllclimbs. I'm 100# ligher than you.

Are you going to Dot-radials to make a class?
J P Stein
MY 914 weighed 1700 to 1780 lbs depending on ballast.
Most AXs were run on a venue that was rough as a cob.
Ride height was 4 1/2 to 5 inches measured from the dough nuts.
21 mm front T bars.
275/300 lb rear springs.
22mm (effective) front AR bar set half hard....none at rear.
Revalved Bilstein shocks......soft on rebound.
Slicks, Cantis in front, 10inch straight sides in rear.
Worked OK on smooth venues also.....but not ideal.

I drove a similar 914 track race car set up for the big track at PIR (which is billiard table smooth) on this same venue......skippng from pillar to post it was uncontrollable.
Woody
My current AX setup is similar to what JP used to run. I have 21mm tbars, a 22mm swaybar, 250 rear springs and 225/275 A6s. 1850 pounds. Its a very predictable car.
J P Stein
There are some mine fields with a suspension set up like I related..

A stiff shassis is needed to *make the suspension do its work*......I'm talkin' bridge stiff. A stock chassis will flex all over hell and make handling inconsistent.

To help the suspension do its work, low friction bushings....not cheep derlin/poly whatever, are needed.

Over 200 lb rear springs can/will cause cracking aound the un-reinforced rear towers long term.....the rougher the venue, the quicker this happens.

Enjoy biggrin.gif
nolift914
QUOTE(Randal @ Sep 17 2013, 08:23 PM) *

QUOTE(nolift914 @ Sep 17 2013, 05:36 PM) *

Is my Autox 914 too stiff?
I am currently running the PO setup, the 914 was set up for club racing with front and rear coil overs. The front is at 330lbs/in which I believe is the equivalent to 25MM torsion bars and the rear is at 230. The 914 is a 4 weighting approx 1780lbs with bias ply slicks. I plan on switching to Dot-R radials. I have always thought for autox go soft on springs and big on bars. Does the paddock crowd have any suggestions for a setup. The autox sites in NYC tend to be on the rough side. I was thinking either 175 lbs/in in front and 140 lbs/in rear or 200 lbs/in front and 180 lbs/in rear.



Currently running 19mm torsion bars with a smart racing bar, with the smallest diameter bar they offered. Had under-steer until I went to the lightest smart racing bar. Front shocks are Koni's set to almost total soft. Rear springs are 240# if I remember correctly. They might be #225, but will check.

With Avon's no under-steer at autox's or hilllclimbs. I'm 100# ligher than you.

Are you going to Dot-radials to make a class?


I am currently running in PCA class M01 and SCCA FP, I am looking to move away from the Canti's due to the limited availability. Cant find soft compounds.
Going to either Radial slicks or Dot-R autox tires. I found this chart listing the front torsion bar spring rate

SIZE ( mm) SPRING RATE ( Lb/in)
18.8 110
21 173
22 210
23 250
24 296
25 350

I believe I have 330lbs / springs on the front which by the chart would be the equivalent to 24.5mm bar, which seems stiffer than those listed in this thread from 19mm to 21mm.

QUOTE(J P Stein @ Sep 18 2013, 06:56 AM) *

There are some mine fields with a suspension set up like I related..

A stiff shassis is needed to *make the suspension do its work*......I'm talkin' bridge stiff. A stock chassis will flex all over hell and make handling inconsistent.

To help the suspension do its work, low friction bushings....not cheep derlin/poly whatever, are needed.

Over 200 lb rear springs can/will cause cracking aound the un-reinforced rear towers long term.....the rougher the venue, the quicker this happens.

Enjoy biggrin.gif

J P

I should have given more details of the 914's current setup, In addition to the front and rear coil-overs on Bilsteins, the front struts have raised spindles. front and rear Elephant racing polybronze bearings, Reinforced rear trailing arms and lower console, full 8 point cage. no reinforcement on front and rear shock towers. Front sway bar (Weltmeister) and no rear bar.

From the setup's listed everyone is softer in front between 125lbs to 175lbs and stiffer in the back 225 to 275. confused24.gif
mskala
I believe your chart is accurate from my memory of 21mm calculation.

Anyway, what do I know, I've never driven anything other than the 914
in anger, but here is my opinion. Yes, you should have the front softer
or equal springs to rear. Since your car is not a street car, overall
stiffer is better, except when the surface gets too bad. Understeer is not
your friend, and can be tuned a bit with the front bar. Also, unless you
have a co-driver, with such a light car it may be difficult to heat up the
tires if you go with something wide for your semi-flares. We do a group
of 4 runs and the first 2 for me are only for heating. If lucky the pressure
goes up by ~4psi then I know I'm in business (with dot-r).

Here is my setup, which I'm pretty happy with as a street car.
Torsion bar: 20mm (yes, these are occasionally available)
Rear spring: 180
Front sway: 19mm weltmeister, set kinda in the middle after tuning
Rear sway: none
Front shock: koni adj
Rear shock: Bilstein non-adj (perch adjustable)
Wavetrac limited slip
about -2deg camber all over
lowered slightly, no spindle change
Wheel: 7.5x16 Fuchs-center, BBS rim
Tire: Kumho V710 215/40/16
No flares
Weight: stock but no tar on interior (~2050)
Engine: 2.2L 'E' six
nolift914
QUOTE(mskala @ Sep 18 2013, 03:43 PM) *

I believe your chart is accurate from my memory of 21mm calculation.

Anyway, what do I know, I've never driven anything other than the 914
in anger, but here is my opinion. Yes, you should have the front softer
or equal springs to rear. Since your car is not a street car, overall
stiffer is better, except when the surface gets too bad. Understeer is not
your friend, and can be tuned a bit with the front bar. Also, unless you
have a co-driver, with such a light car it may be difficult to heat up the
tires if you go with something wide for your semi-flares. We do a group
of 4 runs and the first 2 for me are only for heating. If lucky the pressure
goes up by ~4psi then I know I'm in business (with dot-r).

Here is my setup, which I'm pretty happy with as a street car.
Torsion bar: 20mm (yes, these are occasionally available)
Rear spring: 180
Front sway: 19mm weltmeister, set kinda in the middle after tuning
Rear sway: none
Front shock: koni adj
Rear shock: Bilstein non-adj (perch adjustable)
Wavetrac limited slip
about -2deg camber all over
lowered slightly, no spindle change
Wheel: 7.5x16 Fuchs-center, BBS rim
Tire: Kumho V710 215/40/16
No flares
Weight: stock but no tar on interior (~2050)
Engine: 2.2L 'E' six


Thanks for the info, you were very quick at the Zone 1 autox. I was having a hard time trying to get heat in the the tires and was looking forward to trying to close the gap on day 2 before the apparent issues.
J P Stein
There are several spring rate for torsion bar charts floating around.
This is the one I use.


Front Rates
Torsion Kw (lb/in) Ks (lb/in)
Dia (mm) (Wheel) (Spring)
16 77 90
17 97 112
18 122 138
18.5 137 154
19 152 170
20 187 207
21 227 249
22 273 298
23 327 355
Randal

Right, no soft compounds with Canti's.

Before you go to radials check out the soft compound Avons. They are expensive, but they work. Also believe the real soft Avon's have more tread on them to start out.
nolift914
QUOTE(Randal @ Sep 19 2013, 09:21 AM) *

Right, no soft compounds with Canti's.

Before you go to radials check out the soft compound Avons. They are expensive, but they work. Also believe the real soft Avon's have more tread on them to start out.


I took a look, what compound do you run A11 or A24
J P Stein
R35 Hoosiers always worked for me. There was most always a string of "others" behind us. It's all in the set up.
nolift914
QUOTE(J P Stein @ Sep 19 2013, 11:27 AM) *

R35 Hoosiers always worked for me. There was most always a string of "others" behind us. It's all in the set up.


I will take a look for the r35's , running the r45's now can't get them hot.
Downunderman
With 330 on the front and 230 on the back the thing must understeer like a pig. If you want to keep the 230's on the back I would drop the fronts to 190. The theory being that the spring rates should reflect the F/R weight distribution which with a teener is roughly 45/55 (on a six at least, don't know what a four is, but cant be much different).

Randal
QUOTE(nolift914 @ Sep 19 2013, 10:47 AM) *

QUOTE(Randal @ Sep 19 2013, 09:21 AM) *

Right, no soft compounds with Canti's.

Before you go to radials check out the soft compound Avons. They are expensive, but they work. Also believe the real soft Avon's have more tread on them to start out.


I took a look, what compound do you run A11 or A24


I'm running A45 for both autox and hillclimbs. Magic actually. Perfect for light weight 914's.

Good idea to decide on front tire size you want (narrow or wide) then ratio your weight balance to the rear tire. In effect you end up with every inch of tire with the same weight, i.e., just like F1. Smaller in front is better.

You're concerned about getting heat into tires, so run narrower tires in the front.
ChrisFoley
QUOTE(Downunderman @ Sep 19 2013, 02:29 PM) *

With 330 on the front and 230 on the back the thing must understeer like a pig. If you want to keep the 230's on the back I would drop the fronts to 190. The theory being that the spring rates should reflect the F/R weight distribution which with a teener is roughly 45/55 (on a six at least, don't know what a four is, but cant be much different).

You have to look at wheel rates to make a valid comparison.
The rear wheel rate is higher than the spring rate.
The front wheel rate is lower than the spring rate, as shown in the chart above.
J P Stein
Next time some expert tells you what spring rate your T bar are do this simple test.
Plop your ass on the front fender. How much do you weigh and how far did the fender drop?......WARNING: If enough sand is pounded up your ass, the fender may go down more. blink.gif
nolift914
I guess my question is what spring rate is equivalent to a 21mm torsion bar for a 914 with front coil-overs and what is equivalent to 19mm.
J P Stein
Looking at the supplied chart the answer would 21mm=250 in lbs & 19mm=170. Did your mom have much trouble toilet training you?

These numbers are approximates.

You'll not find an easy path to 914AX Nirvana without *actual testing*. This involves spending money for parts and then trying them out......or you can set back and seek more data.
Randal
Speaking of research, have you asked Tom Provasi how he had the car set up when it was a big autox winner?
nolift914
QUOTE(J P Stein @ Sep 21 2013, 07:05 AM) *

Looking at the supplied chart the answer would 21mm=250 in lbs & 19mm=170. Did your mom have much trouble toilet training you?


These numbers are approximates.

Since you stated their were various spring rate charts out there, I was looking for a consensus from someone who has run front coil-overs. Its an easy choice with torsion bars either 19 or 21 but with charts listing a 21mm from 170 to 250 and a 19mm from 115 to 175. So its not as easy as potty training.


You'll not find an easy path to 914AX Nirvana without *actual testing*. This involves spending money for parts and then trying them out......or you can set back and seek more data.


I have been AutoX for 25 years but the last 15 have been in a 944, I understand the testing process, that's why I post questions in the paddock so the "experts" can trim the expense and I can learn from them. Sorry I post such simple questions as I do.
mskala
QUOTE(nolift914 @ Sep 22 2013, 10:41 AM) *

I have been AutoX for 25 years but the last 15 have been in a 944, I understand the testing process, that's why I post questions in the paddock so the "experts" can trim the expense and I can learn from them. Sorry I post such simple questions as I do.


These are not simple questions as evidenced by some people posting
charts that can't all be correct, and feeling like there's only one way to do shit.

You picked up a car that was obviously set up for something else, so you
definitely have to put the time in to get it to work and feel the way you want
it. But definitely narrow it down by asking here too.
Woody
agree.gif
Randal
QUOTE(nolift914 @ Sep 22 2013, 07:41 AM) *

QUOTE(J P Stein @ Sep 21 2013, 07:05 AM) *

Looking at the supplied chart the answer would 21mm=250 in lbs & 19mm=170. Did your mom have much trouble toilet training you?


These numbers are approximates.

Since you stated their were various spring rate charts out there, I was looking for a consensus from someone who has run front coil-overs. Its an easy choice with torsion bars either 19 or 21 but with charts listing a 21mm from 170 to 250 and a 19mm from 115 to 175. So its not as easy as potty training.


You'll not find an easy path to 914AX Nirvana without *actual testing*. This involves spending money for parts and then trying them out......or you can set back and seek more data.


I have been AutoX for 25 years but the last 15 have been in a 944, I understand the testing process, that's why I post questions in the paddock so the "experts" can trim the expense and I can learn from them. Sorry I post such simple questions as I do.


Not trying to be flippant telling you to contact Tom P. He has a painting company in Santa Cruz and I'm sure would talk to you about his autox setup. You'd be miles ahead putting the car back to where he had it, then tune on. biggrin.gif
J P Stein
First let me say there are MAYBE 6-8 truly fast 914 AXers in this country.
There are exactly 0 944s (or other Porsches) that can come close to them.
I know of only 2 or 3 that compete in SCCA AXs at a national level (or semi-national) at the Prepared level You can rest assured that these folks have their shit wired and will undoubtedly blow the doors of "pretenders" in head to head competition.

These guys didn't just appear from nowhere tho one of them just recently bought a well developed ride (With a pee pot full of money in it).

As far as I know the 6-8 group went thru the steps of up thru the time charts so they *know* the way. Since the OP has a balls out race car, they are both his competition and his best source of pertinent data on how to get there. That doesn't mean one doesn't need to use his head and go solely on the data supplied. If you wanna be a casual AXer, fine, the info s there.......but the guys that have it together
are not casual and aren't gonna lead you by the hand.....chances are they didn't get such help.
In my experience, PCA AXers fall into the casual vein.......all well & good but meat & potatoes for the hard core 6-8..
nolift914
Lesson learned, do not reply to a post after 14hr work day. I did not mean to sound grumpy or po'ed. I view this forum as my greatest asset in the quest to get my 914 to be a well sorted autox'er.


QUOTE(mskala @ Sep 22 2013, 02:04 PM) *

QUOTE(nolift914 @ Sep 22 2013, 10:41 AM) *

I have been AutoX for 25 years but the last 15 have been in a 944, I understand the testing process, that's why I post questions in the paddock so the "experts" can trim the expense and I can learn from them. Sorry I post such simple questions as I do.


These are not simple questions as evidenced by some people posting
charts that can't all be correct, and feeling like there's only one way to do shit.

You picked up a car that was obviously set up for something else, so you
definitely have to put the time in to get it to work and feel the way you want
it. But definitely narrow it down by asking here too.


Mskala
You are correct, I am trying to make sound decisions regarding changing a well developed club racing 914 which has been set up for cantilevered slicks to a Autox 914 running either bias ply or radial slicks. I don't believe the conversion is comparable to "Potty training"

QUOTE(Randal @ Sep 22 2013, 06:16 PM) *

QUOTE(nolift914 @ Sep 22 2013, 07:41 AM) *

QUOTE(J P Stein @ Sep 21 2013, 07:05 AM) *

Looking at the supplied chart the answer would 21mm=250 in lbs & 19mm=170. Did your mom have much trouble toilet training you?


These numbers are approximates.

Since you stated their were various spring rate charts out there, I was looking for a consensus from someone who has run front coil-overs. Its an easy choice with torsion bars either 19 or 21 but with charts listing a 21mm from 170 to 250 and a 19mm from 115 to 175. So its not as easy as potty training.


You'll not find an easy path to 914AX Nirvana without *actual testing*. This involves spending money for parts and then trying them out......or you can set back and seek more data.


I have been AutoX for 25 years but the last 15 have been in a 944, I understand the testing process, that's why I post questions in the paddock so the "experts" can trim the expense and I can learn from them. Sorry I post such simple questions as I do.


Not trying to be flippant telling you to contact Tom P. He has a painting company in Santa Cruz and I'm sure would talk to you about his autox setup. You'd be miles ahead putting the car back to where he had it, then tune on. biggrin.gif


Randal
I was not responding to your post, but thank you for the advice. I was planing on contacting tom for the history of the 914, hadn't thought of asking about setup. biggrin.gif

QUOTE(J P Stein @ Sep 23 2013, 06:22 AM) *

First let me say there are MAYBE 6-8 truly fast 914 AXers in this country.
There are exactly 0 944s (or other Porsches) that can come close to them.
I know of only 2 or 3 that compete in SCCA AXs at a national level (or semi-national) at the Prepared level You can rest assured that these folks have their shit wired and will undoubtedly blow the doors of "pretenders" in head to head competition.

These guys didn't just appear from nowhere tho one of them just recently bought a well developed ride (With a pee pot full of money in it).

As far as I know the 6-8 group went thru the steps of up thru the time charts so they *know* the way. Since the OP has a balls out race car, they are both his competition and his best source of pertinent data on how to get there. That doesn't mean one doesn't need to use his head and go solely on the data supplied. If you wanna be a casual AXer, fine, the info s there.......but the guys that have it together
are not casual and aren't gonna lead you by the hand.....chances are they didn't get such help.
In my experience, PCA AXers fall into the casual vein.......all well & good but meat & potatoes for the hard core 6-8..


J P Stein
You are correct, I guess I am a Casual PCA Axer. But than doesn't mean I don't have the desire to be as quick as possible on any given Sunday. I am sure that I was quicker at the age of 23 than I am now at 46. I don't have the time or budget to develop the 914 for the "national level". With that said would like to develop the 914 as far as possible, which is why I post here. I am not looking to be lead by the hand. I am looking for advice from members who are currently running Ax 914 with current generation Slicks. My past experience ended in the 90's with the first generation r-comps. The addition of front coil-covers makes it more complex due to the lack of other 914's using them.
J P Stein
Coil overs intrude on the space for tires.
Using std offset 8" Fuch and canits up front, the tires cleared the strut tube (Bilsteins without dust covers) by 1/4".....not much room for tire deflection, but it worked. After fighting a scrub radius induced push, minimized it the best I could.

"Grumpy" is my middle name.
Randal
[quote name='nolift914' date='Sep 25 2013, 06:43 AM' post='1931639']
Lesson learned, do not reply to a post after 14hr work day. I did not mean to sound grumpy or po'ed. I view this forum as my greatest asset in the quest to get my 914 to be a well sorted autox'er.


[quote name='mskala' post='1930148' date='Sep 22 2013, 02:04 PM']
[quote name='nolift914' post='1929988' date='Sep 22 2013, 10:41 AM']
I have been AutoX for 25 years but the last 15 have been in a 944, I understand the testing process, that's why I post questions in the paddock so the "experts" can trim the expense and I can learn from them. Sorry I post such simple questions as I do.
[/quote]

These are not simple questions as evidenced by some people posting
charts that can't all be correct, and feeling like there's only one way to do shit.

You picked up a car that was obviously set up for something else, so you
definitely have to put the time in to get it to work and feel the way you want
it. But definitely narrow it down by asking here too.
[/quote]

Mskala
You are correct, I am trying to make sound decisions regarding changing a well developed club racing 914 which has been set up for cantilevered slicks to a Autox 914 running either bias ply or radial slicks. I don't believe the conversion is comparable to "Potty training"

[quote name='Randal' post='1930300' date='Sep 22 2013, 06:16 PM']
[quote name='nolift914' post='1929988' date='Sep 22 2013, 07:41 AM']
[quote name='J P Stein' post='1929592' date='Sep 21 2013, 07:05 AM']
Looking at the supplied chart the answer would 21mm=250 in lbs & 19mm=170. Did your mom have much trouble toilet training you?


These numbers are approximates.

Since you stated their were various spring rate charts out there, I was looking for a consensus from someone who has run front coil-overs. Its an easy choice with torsion bars either 19 or 21 but with charts listing a 21mm from 170 to 250 and a 19mm from 115 to 175. So its not as easy as potty training.


You'll not find an easy path to 914AX Nirvana without *actual testing*. This involves spending money for parts and then trying them out......or you can set back and seek more data.
[/quote]

I have been AutoX for 25 years but the last 15 have been in a 944, I understand the testing process, that's why I post questions in the paddock so the "experts" can trim the expense and I can learn from them. Sorry I post such simple questions as I do.
[/quote]

Not trying to be flippant telling you to contact Tom P. He has a painting company in Santa Cruz and I'm sure would talk to you about his autox setup. You'd be miles ahead putting the car back to where he had it, then tune on. biggrin.gif
[/quote]

Randal
I was not responding to your post, but thank you for the advise. I was planing on contacting tom for the history of the 914, hadn't thought of asking about setup. biggrin.gif

Tom and his wife are pretty serious drivers, with substantial records in all their cars.
J P Stein
When administrating the "butt test", I weighed 175 lbs. When I plopped my ass on the front fender of my 914 W/21mm T bars, it went down about 1/4" inch.
Had it gone down about 1 inch, that would have made the 173s inch pound pretty close.........can you skull this out? So much for THAT chart. Dial in all the wheel rate vs spring weights you want......still don't work. Sometimes KISS (& common sense)counts.
nolift914
QUOTE(J P Stein @ Sep 26 2013, 08:53 AM) *

When administrating the "butt test", I weighed 175 lbs. When I plopped my ass on the front fender of my 914 W/21mm T bars, it went down about 1/4" inch.
Had it gone down about 1 inch, that would have made the 173s inch pound pretty close.........can you skull this out? So much for THAT chart. Dial in all the wheel rate vs spring weights you want......still don't work. Sometimes KISS (& common sense)counts.


Setting all the sand filled butt tests aside, I am retaining the 230lb rear springs and going start with 200lb front springs. In addition I have found a set of Hoosier R35 take offs from the SCCA runoffs. Thanks for all the information and setup advice.
ChrisFoley
QUOTE(nolift914 @ Sep 27 2013, 09:00 AM) *

...
I am retaining the 230lb rear springs and going start with 200lb front springs. In addition ...

I predict that will make the car loose.
J P Stein
QUOTE(Racer Chris @ Sep 27 2013, 09:31 AM) *

QUOTE(nolift914 @ Sep 27 2013, 09:00 AM) *

...
I am retaining the 230lb rear springs and going start with 200lb front springs. In addition ...

I predict that will make the car loose.


Could be, but loose is what you want at AX. The adjustable front AR bar is to control "How loose".

I predict a lift of the inside rear tire.
nolift914
QUOTE(J P Stein @ Sep 27 2013, 11:12 AM) *

QUOTE(Racer Chris @ Sep 27 2013, 09:31 AM) *

QUOTE(nolift914 @ Sep 27 2013, 09:00 AM) *

...
I am retaining the 230lb rear springs and going start with 200lb front springs. In addition ...

I predict that will make the car loose.


Could be, but loose is what you want at AX. The adjustable front AR bar is to control "How loose".

I predict a lift of the inside rear tire.


I haven't changed the springs need to confirm the actual rates on the car currently, after running the last event of the season with a good set of Hoosier R35's I believe most of my handling issues were as a result of my tires not suspension. The R35's have enough grip to the awaken the suspension. I finished 2nd overall out of 63 cars only .4 sec behind a very fast well setup 911 GT3. I was 1st in PAX smilie_pokal.gif

IPB Image
Woody
Awesome. Did you get a video?
nolift914
QUOTE(Woody @ Nov 12 2013, 08:27 AM) *

Awesome. Did you get a video?

The battery in my gopro died after the first run. hissyfit.gif
Chris Pincetich
OMG isn't it always about the tires? dry.gif biggrin.gif beerchug.gif
Sounds like you had a great day at the AX races!
nolift914
QUOTE(ChrisNPDrider @ Nov 13 2013, 09:45 AM) *

OMG isn't it always about the tires? dry.gif biggrin.gif beerchug.gif
Sounds like you had a great day at the AX races!

Yes its allways about the tires, just didn't think there was as big of a difference from hoosier 45's to the 35's
sean_v8_914
lots of great recommendations from very experienced racers here...

springs store energy. stiff springs store more so the release (off-loading) is quicker. more skill is required to manage that faster release and to be ahead of the car as you go higher in spring rate.
shocks dampen the spring energy. shock valving should be matched to spring rate. big changes in spring rate require changes in damper rate.

im sure many will disagree with the correlation between spring rate and skill level.
nolift914
QUOTE(sean_v8_914 @ Nov 15 2013, 12:19 PM) *

lots of great recommendations from very experienced racers here...

springs store energy. stiff springs store more so the release (off-loading) is quicker. more skill is required to manage that faster release and to be ahead of the car as you go higher in spring rate.
shocks dampen the spring energy. shock valving should be matched to spring rate. big changes in spring rate require changes in damper rate.

im sure many will disagree with the correlation between spring rate and skill level.


I am sure you are correct, that why I post here. I am trying to learn as much a possible. The 914 has re valved bilstein's which I now believe are matched to the springs. I think what I was experiencing was a high spring rate with a very low grip level from the med compound r45's which resulted in quick under-steer with little warning. With the increased grip level of the 35's the suspension is working as designed. In addition to the driver catching up to the car with the added seat time.
Looking foward to next season!
Woody
QUOTE(nolift914 @ Nov 15 2013, 07:16 PM) *

QUOTE(sean_v8_914 @ Nov 15 2013, 12:19 PM) *

lots of great recommendations from very experienced racers here...

springs store energy. stiff springs store more so the release (off-loading) is quicker. more skill is required to manage that faster release and to be ahead of the car as you go higher in spring rate.
shocks dampen the spring energy. shock valving should be matched to spring rate. big changes in spring rate require changes in damper rate.

im sure many will disagree with the correlation between spring rate and skill level.


I am sure you are correct, that why I post here. I am trying to learn as much a possible. The 914 has re valved bilstein's which I now believe are matched to the springs. I think what I was experiencing was a high spring rate with a very low grip level from the med compound r45's which resulted in quick under-steer with little warning. With the increased grip level of the 35's the suspension is working as designed. In addition to the driver catching up to the car with the added seat time.
Looking foward to next season!

Driver catching up to the car. Story of my life.
Randal
QUOTE(Woody @ Nov 15 2013, 05:53 PM) *

QUOTE(nolift914 @ Nov 15 2013, 07:16 PM) *

QUOTE(sean_v8_914 @ Nov 15 2013, 12:19 PM) *

lots of great recommendations from very experienced racers here...

springs store energy. stiff springs store more so the release (off-loading) is quicker. more skill is required to manage that faster release and to be ahead of the car as you go higher in spring rate.
shocks dampen the spring energy. shock valving should be matched to spring rate. big changes in spring rate require changes in damper rate.

im sure many will disagree with the correlation between spring rate and skill level.


I am sure you are correct, that why I post here. I am trying to learn as much a possible. The 914 has re valved bilstein's which I now believe are matched to the springs. I think what I was experiencing was a high spring rate with a very low grip level from the med compound r45's which resulted in quick under-steer with little warning. With the increased grip level of the 35's the suspension is working as designed. In addition to the driver catching up to the car with the added seat time.
Looking foward to next season!

Driver catching up to the car. Story of my life.



+1 smile.gif
dlestep
Use charts as reference to get yourself in the neighborhood. Every 914 handles
differently under the same settings and every driver has their own style.
Test, adjust, test, adjust, test and accept changes using your own ass.
There are so many variables. But, you know that...
What works great at Sebring, sucks at Lime Rock.
If you think tires are important, try asking someone what pressures they're running.
Randal
QUOTE(dlestep @ Nov 16 2013, 11:15 AM) *


If you think tires are important, try asking someone what pressures they're running.



Some of the best kept secrets.....
Woody
I don't run with any of you so this is what I run. 225/45/15 front, 275/35/15 rear. A6s. 19 front cold, 18 rear cold. 22 front hot, 21 rear hot. Car is 1850 pounds without driver.
Randal
QUOTE(Woody @ Nov 16 2013, 12:39 PM) *

I don't run with any of you so this is what I run. 225/45/15 front, 275/35/15 rear. A6s. 19 front cold, 18 rear cold. 22 front hot, 21 rear hot. Car is 1850 pounds without driver.



Now you've gone and done it!
Woody
QUOTE(Randal @ Nov 16 2013, 02:58 PM) *

QUOTE(Woody @ Nov 16 2013, 12:39 PM) *

I don't run with any of you so this is what I run. 225/45/15 front, 275/35/15 rear. A6s. 19 front cold, 18 rear cold. 22 front hot, 21 rear hot. Car is 1850 pounds without driver.



Now you've gone and done it!

unsure.gif
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