Coilover spring rates Front and Rear for autox?????

[Lozer]

So I'm playing with my dime and i measured the coilovers and i currently have 625# in the front and 650# in the rear.

 

I ordered a set of 275s for the front and im going to move the 625s to the rear. 

 

I know 625 is going to probably be too stiff and im going to lift the tires. 

 

71 510, 1-1/8th front sway bar, no rear bar, 

 

2.25- camber in front and -2ish in back.

 

Whats everyone running for AutoX

[DISLEXICDIME]

625 woh I thought my 350 front 275 rear was high

[datzenmike]

650 seems twice or more over what would normally be called excessive.

 

What's the coil spring diameter outside to outside?

Whats the wire thickness?

How many coils are free to move. Start counting from where the coil leaves the support of the spring perch and just touches the top hat.

[Lozer]

Od of spring is 3.5" 

Diameter of wire is 12mm

Free height of spring is 7.25" rear and 6.5" front

 

Front has 6 coils total but only 4 active

Rear has 7 coils total with 5 active.

[datzenmike]

Fronts...... 605.9 lb/in. This is pretty close to your 625. Call it the same.

 

Rears...... 484.7 lb/in

 

The rear can't be stiffer if it has more coils.

[Lozer]

Thanks Mike you made me double check my math. Looks like i'll keep the rears for now as i do like some oversteer. now to figure out ride height. 

 

How much of a rake should i have? currently from the buttom of the pinch weld I'm at 4.5" in front and 5.5" in rear.

[q-tip]

625 woh I thought my 350 front 275 rear was high

No shit, I'm running the same thing.

 

 

The "natural" rake of a 510 is about an inch but the only way you will really know what you need to run is to put the car on some corner weights and even everything up.

[DISLEXICDIME]

Yup corner weights are the way to go

[Icehouse]

WOW!!  Way to stiff.  I run 300's front and rear and I think for my tread wear 200 tires they are on the edge of to stiff.  Our track is super bumpy, when I ran softer springs I had bottoming out issues which is why I switched to 300's.  I also run no rear bar.  I have 1 degree of front camber and 3.4 in the rear.  To much but they rub if I adjust any more out.  I even mini got mini tubbed it.  

 

 

[Lozer]

yea ill be running 275 fronts and 500 ish rear this weekend. Ill grab a softer set before the next AX for the rear. Like I said tho I love oversteer.

 

 

 

My previous AX car was a 89 vett with 450ish hp and tq. Wildly different animal. Won my class for 2 years before i sold it.

 

http://vid68.photobucket.com/albums/i15/stryder42/Tom1_zps7af63260.mp4

 

[DISLEXICDIME]

Dang Jeff 3.4 in the rear . I need to try that .

[q-tip]

So are you running rear coilovers or using the factory spring location?

[Lozer]

rear coilovers. 

 

Im thinking of moving the 500 lbs springs to the front coilovers and running the new 275s ive got in the back.

 

Alternatively I could cut the stock springs i have down 2 coils to bring them up to 750 lbs ish

[q-tip]

That's alot of stress on that lower shock mount in the rear.

[Lozer]

I know right. Ive been beating around with these springs for a month or 2 now with 1 AX already soooo I guess its fine. (no cracks or bending)

[Lozer]

ok so I scored some stock 88 mustang front springs and cut them down to 4 coils which measured out to be 1050 lbs for rear springs in the stock location. 

 

worked out great.

[510T]

All one color?!

 

See you tomorrow!

[Zeusimo]

I Have #300 On MR2 AGX W/ 225/45/15 Toyo RA1, Cusco Strut Bar, L16, -1.5 Camber, +6 Caster

Seems A Tad Soft For Me In The Canyons.. Especially Downhill

Thinking About Going 350 But I'm Waiting To Get A Stiffer Sway Bar Before I Make A Decision

I Noticed After Switching From 280zx Brakes To Willwood, Swastika Wheels To SSRs,

Cheap Tires To 100 Treadwear, Strut Bar. The Spring Rate Went Up

Also Those AGX Shocks Are Really Cheap...

Going With Koni Next Time Around

[Lockleaf]

All those capital letters made me motion sick reading that

[Duke]

I run 350# all the way around...with some other tricks that can be found in my build thread.

[q-tip]

I run 350# all the way around...with some other tricks that can be found in my build thread.

Listen to this man!

[datzenmike]

For purpose built autoX the sky's the limit. The more it becomes a 'race car' the less it's a 'street car'.  

[Lozer]

I read duke's entire thread and im taking tips from it for the build. I am building this car as a daily more so then an autox only bucket. I think I will stay with 275s for now, I scored some super sticky slicks and i cant wait to see how they work with this set up. Also welding the rear diff before the next ax. 

[paradime]

Ok Slow down there. You do not want a welded dif in a daily driver. I have 300lb springs all round with a 1.25" front sway bar and a 5/8" rear. That being said, that works for me because my car was purpose built so that all the suspension modifications and components work right together. Trust, there is more than one way to skin this suspension cat though, and many things can influence it; like the weight, HP, your driving style, etc. You really need to know your way around the 510's suspension before throwing huge mods at it like a welded dif. When you change one thing, most likely you'll need to adjust, or modify others to make it work right. Shit can get really twisted if you don't pay attention everything from the ground up.

[datzenmike]

Better control with an open diff if stock hp engine. Welded diffs introduce under steer. You did say autoX not drifting.