Autox Spring rate help, Too Stiff? Options

[nolift914]

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]

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]

(IMG:style_emoticons/default/agree.gif)

[Randal]

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. (IMG:style_emoticons/default/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.

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"

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. (IMG:style_emoticons/default/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. (IMG:style_emoticons/default/biggrin.gif)

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. (IMG:style_emoticons/default/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. (IMG:style_emoticons/default/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]

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]

...
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]

...
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]

...
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 (IMG:style_emoticons/default/smilie_pokal.gif)

(IMG:http://www.914world.com/bbs2/uploads_offsite/scontent-b-iad.xx.fbcdn.net-10399-1384263372.1.jpg)

[Woody]

Awesome. Did you get a video?

[nolift914]

Awesome. Did you get a video?

The battery in my gopro died after the first run. (IMG:style_emoticons/default/hissyfit.gif)

[Chris Pincetich]

OMG isn't it always about the tires? (IMG:style_emoticons/default/dry.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/beerchug.gif)
Sounds like you had a great day at the AX races!

[nolift914]

OMG isn't it always about the tires? (IMG:style_emoticons/default/dry.gif) (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/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]

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]

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.