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Stock vs coilovers...worth how much time on a track?

ArizonaGT said:
Yeah I am following all of Vorshlag's stuff on S197forum and corner-carvers; I love what they are doing and all the info they share.

They're pretty awesome. I've been reading their stuff for years. Everybody who works there are really great, I felt like I knew them personally and they were old friends during my dealings with them. Really, their customer service is part of what made me decide to purchase ASTs.
Jimmy Pribble said:
Not as much as the difference that driver skill can make. I always ask myself something like this - could I beat Hans Stuck if he were in a stock Boss and I were in a Boss + coilovers? No? Then I better spend my money on track time. Now, don't get me wrong, I'm going to put some kind of suspension on my car, because weeble-wobbling around the track is just frustrating, but I'm tempering my upgrade choices with what I said before. Also, for some people (not me) money is not really a problem, so more power to them.

Maybe a better answer to your question is to clear-up why coilovers are better for a race car. It doesn't have all that much to do with outright performance at any given track. How is a coilover setup different than standard, if the standard setup duplicated the effective spring rates and dampers? The reason for a coilover setup is for a) corner-balancing and b) the ability to easily and cheaply adjust spring rates for any given track. For a standard setup, how many spring sets does Ford Racing make for the Mustang? Three? But once you go to a coilover, you can have any spring rate you want, front and back, for $50 a spring new. Since coilover springs are of just a couple of standard diameters, you can buy them used for dirt cheap all day long.

My main point is that there are very good reasons to go with a coilover, but an absolute advantage in lap times vs. a standard suspension upgrade is probably not one of them. IMO. ;)

Jimmy, As always you manage to put a great prospective on our sport. There is an additional benift for coil overs for the advanced driver. Loaded front tire wear is a major problem because of the high body roll. You can not push the car for long periouds before you scrub the outer loaded edge of the front tire. The p springs are not strong enough either. I have driven two other 302 cars one with Moton and one with Dynamic coil overs. What a difference. I can turn about the same lap times with my semi. stock LS but not for long. With 2.7 neg.camber there is still way to much body roll for the roll center. This from the racer point of view. Best


Too Hot for the Boss!
Zquez said:
I have the 4150s that I just put on and they are a work of art. The nice thing about the 4150s compared to other single adjustables in the price range, is that they can be upgraded to 4250 doubles down the road.

I've got Terry's AST 4100s with the 4150 internals. These were prototypes with the DDP (dual digressive piston). I think you'll like them a lot! I've run 4100, 4200 and 5200s on my M3. My favorite were the 4200s. I could really get them dialed in on a particular track... great shocks.

As far as servicing, AST USA is located in texas so no overseas shipping.

Brian (AST) has also gone around the country training individual shops. Check with him as there may very well be someone closer to you for rebuilds. Mine always go back to AST USA in DFW, but I do have a shop local in Ft. Collins that can rebuild them if I ever need them in a hurry.
Good choice! I finally got to take my GT out for a spin today with mine. Even on my worn out tires, the car was just plain faster in a turn. It was like the ASTs were the key to opening the grip box. The car corners flatter and can put the power down even better. Best part -- since my GT is also my (usual) daily driver -- it rides just as good if not better than my D-specs on lowering springs. I have the 450/175 rates. I cant wait to take mine to the track next month. Zero noise too even with spherical and poly everything.
ArizonaGT said:
Sweet! What spring rates did you go with?

Race line - 550 front / 250 rear ...seems weird they use such soft springs in rear (compared to an M3 say where it is much higher)

LindsayEOD said:
Those look awesome DD GT3!! Please give us a review after you track them.

Will do, going back to WSIR next friday so hopefully I get them before and I have some solid times there and at buttonwillow. So can see if I run faster

sidenote..I had the maximum motorsport Camber Plates which dont fit these! Grrr so have to get the Vorshlag plates with them...

if anyone needs MAXIMUM MOTORSPORT camber plates ill be selling mine!


Because racecar.
Arizona, USA
That's about the same rates I'm running on my KWs, 515/230...anything much stiffer than that and it's tough to get enough weight on the rear to get traction on exit from low speed corners. Plus it allows you to be more flexible with your swaybar config. I think you will like it.

I still have my other KW rear springs (400lbs/in!!!) which still work fine for high-speed tracks. I might play around with them at Chuckwalla.
DD GT3 RD said:
sidenote..I had the maximum motorsport Camber Plates which dont fit these! Grrr so have to get the Vorshlag plates with them...

if anyone needs MAXIMUM MOTORSPORT camber plates ill be selling mine!

I was in the same boat and ended up getting the Vorshlag plates. However, if you get the new spring seat from MM ($140) and change the fronts from 60 MM to 2.5" springs, Im pretty sure they'll work.
I have these for sale if anyone's interested. I had a custom plate made to work with MM camber plates. There are also lower perches for factory or factory type springs included.


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DD GT3 RD said:
^ which series are those? How did u like them? Why selling?

I'm not familiar with AST part numbers, but they are single adjustable. I purchased them from Sam Strano and Mike Snyder (National Championship winning Shelby Mustang) Fall of 2010 and ran them for a few AutoX races including the SCCA National Championships in Lincon, NE. Co-Driver and I placed 2nd and 5th in ESP respectively so they definitely work. I switched to Penske's for adjust ability and custom valving. The AST's have Sam's valving.


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