Swap shocks for ACR

[ACRBruce]

I have this one crazy idea and would like to ask the forum's opinion but this is just a brainstorming idea so please don't flame me for suggesting...
I've trying to dial in my ACR's KW shock settings for the street and after trying just about all the combination of compression and rebound, the car is still very bouncy for the street, so much so that my stomach muscle starts to ache after drives over an hour as the car bounces up and down, I tend to flex my stomach muscle to hold myself in place. OK OK I already have a six pack (of beer) and don't want to do any more crunches sitting up in a car. I know it is a necessary evil to have 800/1000 pound-inch spring rates in the ACR to work with the 1000+ pounds of down force at 150+ MPH. I know I know, but I also know I won't be doing 150+ that often. I'd see 120 or maybe 130 max. on most of the tracks that I run in, so maybe once a year I'll see 140+. But the car is just too good not to be driven more, and I would if the suspension was softer. So here comes the idea of getting Motons or a set of used OEM shocks w/ Eibach/lowering caps and run mayb 500/800 springs and this should still be good for 120-130MPH??? Does anyone have the downforce ratings of the car at 120MPH. Or say it is arond 300 pounds, so it is just like carrying a fat passenger around, no big deal, just add a couple of clicks to the Motons? Right? And for that once a year session that I may run faster, back goes the KW's.

 

[Flash1034]

Ill take your ACR shocks off your hands when you get Motons...Seriously.

Flash

 

[3SRTsandGTS]

According to Viper Magazine (Summer 2008), the downforce at 120 MPH is approximately 625 lbs +/- 15 depending on rear wing hole position.

 

[ACRBruce]

Ill take your ACR shocks off your hands when you get Motons...Seriously.

Flash

I'll keep the KW's for faster tracks.

 

[ACRBruce]

According to Viper Magazine (Summer 2008), the downforce at 120 MPH is approximately 625 lbs +/- 15 depending on rear wing hole position.

Does anyone know how much downforce the optional Areokit generates?

 

[CCBrian]

Um but the Moton's are better on the track....especial the 3 ways...and the Motons will need rebuilding much more often so a very poor choice for the street...keep what you have and just drive it!!!!

 

[Grant]

Even with the recommended street settings, the suspension is too stiff for you? Wow, I thought it was really comfortable on those settings...

I don't think less spring rate is going to cause any serious issues. You'd sacrifice handling and may have some wheel-to-fender-liner contact where you wouldn't have with stiffer springs, but thats it. If you experience contact, you could always raise the car up some.

You could also run without the front splitter, and set the wing to position "1". Taking some rake out of the car will also lower downforce quite a bit.

 

[ACRBruce]

Um but the Moton's are better on the track....especial the 3 ways...and the Motons will need rebuilding much more often so a very poor choice for the street...keep what you have and just drive it!!!!

Motons are great for the track is a given, but don't tell me no one uses their Motons for the street. I for one have a set of Motorsport Two Ways on my Ford GT that I find some plush, much better damping and ride than the OEM Ford GT shocks. So why should I punish myself on the street with the KW's?

 

[ACRBruce]

Even with the recommended street settings, the suspension is too stiff for you? Wow, I thought it was really comfortable on those settings...

Some have commented that the ride was good but to me, yes, the car is bouncy and I'm used to stiff riding cars already, my recents cars are 996 GT3 with Yoko AO48's (very stiff), Lotus Elise while still on OEM LSS suspension w/ Yoko AO48 tires (read stiffer), and a Ferrari Challenge Stradale with very hard suspension bushings. The GT3 and Lotus's ride is more harsh but the ACR has more up and down movements, a lot more. If you hit a bump going 60, it will launch you out of your seat and make your head hit the headliner. The Ferrari Challenge Stradale rides like a Cadillac compares to the ACR. One thing that the ACR has going for it is the isolation as even though the car has a lot of verticle movements, it never bottoms out so ride harshness is at a mininum. I never had to **** up my stomach muscle before the ACR. And of course and again, none of the other cars generate nearly as much downforce as the ACR.

 

[jpas]

I run the Penske three way adjustables (Comp hi & lo + rebound) on my SRT with 1000 & 950 springs on the street. It rides way smoother then the stock factory shocks.

The KW's aren't the greatest on the rebound settings (way too limited), the Motons or Penske's have a much greater adjustment range. Try them, you will love them (if you don;t mind the price)

 

[Nader]

I run motons and absolutely love them. For me they were the perfect compromise for street and track use. Hell the ride quality compared to the stock setup is night and day.

 

[Viper X]

Bruce,

I run Moton Club Sports on two SRT's and love them. One of them is a pure street car, the other a "mostly" street car. My wife drives it at Viper Days once a year.

I also run Moton Race Shocks on my GTS ACR track car. They work extremely well on it too both on the street and at the track, though it doesn't see much street time any more.

Someone above said that Motons needed to be rebuilt frequently. That has not been the case with my 3 sets. I have about 40 K miles on one set, 30 K miles on another and 15 K on another. All shocks are still working as they should.

Call JonB for Moton Club Sport Shocks. He'll take good care of you. 500 / 800 lb Eibach 8-inch springs are good compromise for the street.

I'm suprised you can't find a comfortable setting for the KW's on the street with your ACR. Feedback from most ACR buyers has been very positive on street ride comfort for a race car. Mine will be here soon and I'll let you know what I come up with. Stock ACR springs are only 518 / 1080 (something like that) which isn't really very stiff. Not sure what air pressures you are running in your tires but you may be able to lower the air in your tires a bit for the street which will help soften the ride. You could change the rear spring rate to 800 or so and that would help a bunch too.

Dan

 

[3SRTsandGTS]

I can appreciate Bruce's experiences pertaining to the ride. Where I live in FL, I have no problems whatsoever. However, my ACR was delivered to me at Eagles Canyon, TX. My wife and I drove the ACR from TX to FL. On portions of I-10, we were bouncing so much that our laughter had us in tears. Hence, I suspect the quality of the roads and temperatures would results in numerous responses being different. With this said, I did not think Dodge could improve upon the GEN III car; I was completely wrong. I have a 2006 T1 prepared Viper, and soon I plan to track my race car and ACR to learn which is faster. It's hard for me to tell by seat of the pants so I am looking forward to what the timers reveal.

 

[ACRBruce]

Bruce,
I'm suprised you can't find a comfortable setting for the KW's on the street with your ACR. Feedback from most ACR buyers has been very positive on street ride comfort for a race car. Mine will be here soon and I'll let you know what I come up with. Stock ACR springs are only 518 / 1080 (something like that) which isn't really very stiff. Not sure what air pressures you are running in your tires but you may be able to lower the air in your tires a bit for the street which will help soften the ride. You could change the rear spring rate to 800 or so and that would help a bunch too.
Dan

Dan,
Thanks for your advise and I'll look into the Motons more as I absolutely love the Motorsport 2Ways on my Ford GT, after 2+ years, they have performed flawlessly. I'm running 29PSI, as recommended by the factory but will experiment with 27. Or maybe I'll just try out 800# springs on the rear KW's.
Another reason I want a more compliant suspension is because I want the car to stick better in bumpy medium speed corners as I am just not comfortable pushing the car on winding roads as the car bobs up and down too much and doesn't feel as planted as it should.

 

[rocman]

I find the car to be very comfortable in the street configuration. If you are not in a hurry, KW is coming out with a retrofit for the stock ACR suspension to make it 3 way. This may help.

 

[Grant]

Another reason I want a more compliant suspension is because I want the car to stick better in bumpy medium speed corners as I am just not comfortable pushing the car on winding roads as the car bobs up and down too much and doesn't feel as planted as it should.

With what damper settings? The problem is that the street settings are very under-damped, i.e. it makes the car behave a bit like it had blown shocks. Good for comfort, unless you're on an unusually bumpy road. Then the thing bobs up and down like a pogo stick. When I first got my ACR, I drove it on a bumpy road with the street settings, and noticed the same thing. It was too scary for aggressive driving on bumpy roads.

I'm running 11/13 compression/rebound on the front and the rear now, and I like it a lot for street use. Increasing rebound without increasing bump will reduce the bounciness without increasing harshness, it over repeated bumps it may be possible for the wheel to hit the fender due too much rebound resistance (I haven't experienced this on my ACR, but I have on another car).

Even at the recommended track settings (i.e., with a lot of rebound damping) I hit my head on the roof, though... I think the seats are just too bouncy. The car stays planted, but I don't.

 

[ACRBruce]

With what damper settings? The problem is that the street settings are very under-damped, i.e. it makes the car behave a bit like it had blown shocks. Good for comfort, unless you're on an unusually bumpy road. Then the thing bobs up and down like a pogo stick. When I first got my ACR, I drove it on a bumpy road with the street settings, and noticed the same thing. It was too scary for aggressive driving on bumpy roads.

I'm running 11/13 compression/rebound on the front and the rear now, and I like it a lot for street use. Increasing rebound without increasing bump will reduce the bounciness without increasing harshness, it over repeated bumps it may be possible for the wheel to hit the fender due too much rebound resistance (I haven't experienced this on my ACR, but I have on another car).

Even at the recommended track settings (i.e., with a lot of rebound damping) I hit my head on the roof, though... I think the seats are just too bouncy. The car stays planted, but I don't.

I've tried various settings in the past month but just haven't found one that I can say is good all around. I started out w/ the factory setting of 1 click from full stiff for both comp and reb in the front and 1/2 in the back, then went progressively stiffer, and since the last time I ran the car in an autocross, I left the car around 5/5 front, and 3/4 rear, but that made the car too stiff for the street.

Today I'm running the orig. factory street setting with 27 cold PSI in all 4 tires.

Many has said the car rides good and it does when hitting lane dividing dots and expansion joints as I barely even feel them. But when the road surface is uneven vertically, then the car would just hop up and down and yes those bouncy seats don't help either. And speaking of the seats, I find the bottom cushion too long and they must have been designed for tall people as I'm only 5'11.

 

[ACRBruce]

Bruce,

...
Call JonB for Moton Club Sport Shocks. He'll take good care of you. 500 / 800 lb Eibach 8-inch springs are good compromise for the street.

I'm suprised you can't find a comfortable setting for the KW's on the street with your ACR. Feedback from most ACR buyers has been very positive on street ride comfort for a race car. Mine will be here soon and I'll let you know what I come up with. Stock ACR springs are only 518 / 1080 (something like that) which isn't really very stiff. Not sure what air pressures you are running in your tires but you may be able to lower the air in your tires a bit for the street which will help soften the ride. You could change the rear spring rate to 800 or so and that would help a bunch too.

Dan

Dan,
Can you confirm if the KW springs are 8" long and I read somewhere its ID is 60mm? I'll see if Jon B can help as any springs whether Eibach or Hypercoil or H&R should work. I'm running 27 PSI now in the tires and the ride is better, but the 800# springs will complete the car.

 

[FikseGTS]

I haven't touched the factory settings on my ACR, the car will bounce quite bit on regular streets that have some dips.... sometimes I feel like I lift out of the seat......

 

[gb66gth]

#1) Get to the gym
#2) Sell the car and buy an SRT10 Coupe. At 120-130 in the ACR you're not coming anywhere near the limits of the car, but at that same 120-130 in the SRT you are closer to the limits (but still not close) of the car and still have the ride quality on the street.

 

[salties]

Some have commented that the ride was good but to me, yes, the car is bouncy and I'm used to stiff riding cars already, my recents cars are 996 GT3 with Yoko AO48's (very stiff), Lotus Elise while still on OEM LSS suspension w/ Yoko AO48 tires (read stiffer), and a Ferrari Challenge Stradale with very hard suspension bushings. The GT3 and Lotus's ride is more harsh but the ACR has more up and down movements, a lot more. If you hit a bump going 60, it will launch you out of your seat and make your head hit the headliner. The Ferrari Challenge Stradale rides like a Cadillac compares to the ACR. One thing that the ACR has going for it is the isolation as even though the car has a lot of verticle movements, it never bottoms out so ride harshness is at a mininum. I never had to **** up my stomach muscle before the ACR. And of course and again, none of the other cars generate nearly as much downforce as the ACR.

How do you like the porsche GT3?

 

[ACRBruce]

#1) Get to the gym
#2) Sell the car and buy an SRT10 Coupe. At 120-130 in the ACR you're not coming anywhere near the limits of the car, but at that same 120-130 in the SRT you are closer to the limits (but still not close) of the car and still have the ride quality on the street.

You're not much help but to answer your questions:
1) I teach martial arts as a hobby
2) I like to fiddle with car setup and if I wanted to setup my Ford GT w/ 850 HP and a 230 MPH top speed for autocross, it is my buiness. I don't need anyone to tell me to go get a ten year old Miata for racing in the parking lot is the way to go.

 

[ACRBruce]

How do you like the porsche GT3?

Raw, great sounding engine when under load - it is the air induction sound that attracts more, the exhaust is kinda quiet, lots of adjustability - adj. f/r sway bar, great driving position, great steering, great smelling leather interior, best brake feel of all the cars I own (not best stopping distance), great OEM clutch - must had 200+ hard launches from car when I traded it in but OEM clutch was still holding up, great transiant response, get feeling that nothing will break while on track and the car just won't heatsoak.
Don't likes are - first gen. ceramic brake had hairline cracks, suspension noise, 415 HP (with a tune) isn't enough nowadays (but was good back in '03 when I first got the car).
If Porsche were to make a direct injected GT3 w/ 500HP, I'll go back in an instant. No I don't want a GT2, not at $200K.