SCCA CAM-C Thread

[Wolverine]

Did you notice much difference when you went to the 11" wheels and 305 tires? I'm not sure what to expect.

What are your current wheel and tire specs? The RE71R is a great tire for autocross regardless of size (Tire is arguably in the top two available right now, with the BFG Rival being the other), and I figured I'd cram as much as I could under the car. This line of thought works as long as you can get heat into them, but be warned that if your runs are spaced out too much time-wise or you don't push the car hard enough for long enough, that a COLD 305 may perform no better than a HOT 285. This was an eye-opener for me.

1. I am also quite pleased with the Steeda Dual Rates, and you're right they're 75%+ as good as coilovers for 25% of the price. It's well worth it to start with Steeda Adjustable dampers and DR springs and learn the platform, before jumping headfirst into the deep end with coilovers (although I envision the handling becoming sublime with a set of them tuned in).

2. Which sways and settings, assuming they're adjustable, do you run on your car? I'm looking into options for a front bar only for 2019...

3. 7,904 rpm and 3.55 gears will get you to exactly 70mph with a 25.5" rear tire height. (8,017 rpm to hit 71mph....engineering brain craves scientific accuracy). Use the calculator at this link to experiment for yourself: http://apexgarage.com/tech/gear_ratios.shtml. I found myself FREQUENTLY riding the rev limiter in 2nd at our local events....to the point of great frustration. The GT350 has so many revs to work with the problem is mostly erased, but I needed to fix this issue or I'd go mad. Rarely was it "worth it" in autocross speak to make a 2-3 upshift followed very quickly by a 3-2 downshift, and let me tell ya... riding that rev limiter for 2-3 seconds on course feels like an ETERNITY. I could casually read a book or brush my teeth with all that free time!! Beyond frustrating... lol

4. Bearings are a minor annoyance to install, but I think they're worth it. I didn't give myself a full season on the car in stock trim to find out. I jumped in with full bearings EVERYWHERE and now the car is firmer and tighter, in a good way. Not much NVH increase, but certainly not quite stock squishy. I just wanted to eliminate all doubt, and confirm that the suspension was being worked as intended and not the rubber bushings strewn all about the chassis. Nobody likes chasing a mystery source of odd tire wear due to deflecting components. Mission accomplished then!

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[NightmareMoon]

I've been on 285 RE71Rs for 5 sets in F Street, so I'm pretty familiar with them This current set will go on the new 11s for the remainder of their life if I can make them last that long. Next set will be 305s.

Currently running the BMR front swaybar (on soft) and the Strano rear bar (on medium), which worked well for the car on stock PP springs, but I think the car feels a little tail happy with the Steeda DR springs. I may lower the Strano bar to soft and try that. The lower setting on the Strano bar is said to be near-stock rates. I really haven't had time to experiment with shock and swaybar settings much since lowering the car.

 

[Wolverine]

285 on 11” is a nice amount of “stretch” if you want to call it that. Great sidewall support keeps the tire from squirming about the wheel during transitions. 305 on 11” is about square/straight sidewalls. 305 on 12” is similar to the 285 on 11” I think. We will find out soon when @TigerFire13 gets his 305s mounted on the new 12”s!

If the Strano rear bar is close to stock rates when setup for DR springs....it would behoove me to just leave my stock swaybar in the rear, and focus on the front. How much stiffer than stock is the BMR front swaybar at its softest setting?

 

[BmacIL]

285 on 11” is a nice amount of “stretch” if you want to call it that. Great sidewall support keeps the tire from squirming about the wheel during transitions. 305 on 11” is about square/straight sidewalls. 305 on 12” is similar to the 285 on 11” I think. We will find out soon when @TigerFire13 gets his 305s mounted on the new 12”s!

If the Strano rear bar is close to stock rates when setup for DR springs....it would behoove me to just leave my stock swaybar in the rear, and focus on the front. How much stiffer than stock is the BMR front swaybar at its softest setting?

19%
Full stiff on BMR bar is 40% stiffer.

 

[NightmareMoon]

Well, I’ve got the 11” wheels and spacers on the car, and the 2019 season is about to start. First event is this weekend (since its not my usual club Im treating it as a test n tune). Just a couple more events on worn out 285 RE71Rs before the new 305s go on.

Im getting like +0.04Gs (1.22 lateral) with the new suspension and wheels with the same very aged tires, so Im expecting fresh rubber will do well.

 

[Bumzo1]

Last season I switched from STP to CAM-C, mostly due to local competition, we've got a pretty healthy CAM-C class with 6-7 regulars and a handful of occasionals. I'll be the first to say that my car is much faster than I am as a driver, since my co-driver would consistently run 1-2s faster... This will only be my third season so I'm still working on my driving skills. This is a dual use car, an almost daily driver and a HPDE/TT/Autox car.

Last season I ran:
JRZ RS1s w/ 600F - 1440R
Vorshlag Camber Plates
BMR Swaybars F/R
19x11 P6GRs square with 305/30/19 RS3s

This season I'm planning to actually go to softer springs, 350F - 980R, mostly because I find the 600/1440 to be too stiff for the street. I'm honestly not sure if the springs are too stiff for the coilovers, or if my coilovers need to be rebuilt, but I find that the car is bouncy in the front on the street and it drives me insane. I purchased the coilovers second hand and never had them tested before I put them on. The coilovers were about 1yr old and were supposedly valved for that spring rate initially but I'm not sure I believe it.

I'm also about to install the BMR rear cradle bushing lockouts and rear subframe brace to hopefully solve the awful wheel hop I get off the line.

I need to replace my RS3s and will likely go with RS4s. I've been pretty happy with the wear rate of the RS3s and am ultimately looking for more seat time than I am ultimate traction. Once I improve my skills a bit more I may invest in some RE-71s but I've seen how fast other people go through them and I'm just not at that level yet.

Lastly, I'm looking into some type of harness to keep me better planted in the seat. I'm still trying to decide between the Quickfit pros, or going with a full harness bar, harness bracket, and 5pt harnesses. I like the versatility of the QFs but I may get a race seat in another year or two and it would be nice to not have to replace all of that when the time comes.

Here's a picture of my car running a set of 18x11 Forgestars and 315 rivals. The wheels and tires belonged to my codriver and unfortunately only made it half the season due to an unfortunate accident driving to an event.

 

[BmacIL]

No matter how good the damping, those springs are going to ride extremely firm.

I've been very happy with 245/980 for spring. It rides well on the street. With the added front camber I'll have to his year, I'll probably go for increased front bar stiffness to keep the balance but also improve slalom attitude.

 

[boardkat]

I guess I must have a pretty high tolerance then. 600-800f/1300-1600r for over 50k miles (and many 14 hour 1k+ mile days) with JRZs and 30-35 profile tires

... pssst, it’s the valving ;)

(and try to stay warm out there @BmacIL!!!)

 

[SteveW]

@Bumzo1, don't go to 350 lb springs, that's too soft. I tried it and believe that 500 lb is the minimum to where the car starts working in CAMC.

For your ride issues try adjusting the shocks first. I too found my car to have a bouncy ride but have been experimenting with shock settings on the street this off-season. I greatly improved the ride by turning down the rebound and have learned the setting points where the suspension control goes from firm/controlled to jerky/bouncy.

I'm currently on 450 lb front and Steeda DR rear with Roush V3 shocks. Those springs are way stiffer than what the shocks were designed with but in terms of ride, it ain't bad.

 

[BmacIL]

I guess I must have a pretty high tolerance then. 600-800f/1300-1600r for over 50k miles (and many 14 hour 1k+ mile days) with JRZs and 30-35 profile tires

... pssst, it’s the valving ;)

(and try to stay warm out there @BmacIL!!!)

I'm holed up in here working from home today. -22 right now...

And yes I'm sure you have a high tolerance! . That's the way to have a super duper fast CAMC car though. To be fair, the front can handle more and still deliver an acceptable ride, and because Mac strut, stiffer can lead to increased grip, since you're maintaining more negative camber.

 

[Bumzo1]

I guess I must have a pretty high tolerance then. 600-800f/1300-1600r for over 50k miles (and many 14 hour 1k+ mile days) with JRZs and 30-35 profile tires

... pssst, it’s the valving ;)

I've done close to 15k on them so far and the harshness really isn't bad at all. I could deal with the 600/1440 if it wasn't for the front of the car basically bobbing up and down going down a mostly smooth road. Like I said, the original vendor claimed they were valved for these spring rates but I'm not convinced that was true. I bought them second hand at a pretty steep discount so I don't have a good way to verify. Do you know what it typically costs to revalve? I have the single adjustable JRZ RS1s.

I may up my spring rates to 450+ again when I'm a little more competitive of a driver but at this stage I'm looking for a little better balance of road comfort/track handling.

 

[jpaulson]

I am jumping into the CAM pool this year....well, more like CAMlight. I have always said, never go full CAM. ;) Should be fun trying to keep up with Dennis in Packwood. First phase is fairly low budget. Better dampers should be in the cards for next year. Here is what I have coming so far.

19x11 SVE wheels
Steeda front wheel spacers
Steeda front endlinks
Steeda diff bushing and bolt upgrade
Steeda subframe bushing supports and alignment bushings
Steeda dual rate springs on my konis
Steeda camber plates
Big front sway bar. Hoping to snag one that Dennis isn't using
Strano rear bar. I already own it

I will start the season using my half worn 285 stones and buy 305's this summer. Probably won't do any power mods for a while.

It looks like a few of you guys are doing something very similar so it should be fun to compare notes. I will try to post updates here as I start getting stuff installed. Our first events of teh year are only a few weeks away.

James

 

[NightmareMoon]

I jumping into the CAM pool this year....well, more like CAMlight. I have always said, never go full CAM. ;) Should be fun trying to keep up with Dennis in Packwood. First phase is fairly low budget. Better dampers should be in the cards for next year. Here is what I have coming so far.

19x11 SVE wheels
Steeda front wheel spacers
Steeda front endlinks
Steeda diff bushing and bolt upgrade
Steeda subframe bushing supports and alignment bushings
Steeda dual rate springs on my konis
Steeda camber plates
Big front sway bar. Hoping to snag one that Dennis isn't using
Strano rear bar. I already own it

I will start the season using my half worn 285 stones and buy 305's this summer. Probably won't do any power mods for a while.

It looks like a few of you guys are doing something very similar so it should be fun to compare notes. I will try to post updates here as I start getting stuff installed. Our first events of teh year are only a few weeks away.

James

Welcome to the CAM club. I'm running the CAM-lite Konis and Steeda DRs too at the moment.

I'll tell ya the first couple of months with the car on a very similar setup to yours and I was having some fun, car felt good, great on track, but sometimes loose powering out of corners. I blamed the old 85% worn 285 RE71s. Then I got my homebrew alignment checked at a real shop and whoa I was nearly 3 degrees of camber in the rear (as I suspected). Turns out the car puts power down A LOT better with 1.9-2 degrees of rear camber than it does with 2.5-3 degrees. Its night and day. Also, slaloms never felt as good on the FS setup as they do with the Steeda DRs and both swaybars. So much more fun.

I'm starting to feel the lack of compression dampening on the Konis. Overall its fine, I can drive the car like this but there are a couple of spots where I the dampening feels a little softer than I'd probably like. Like you, proper shocks are going to have to wait while the budget recovers from the rest. I don't see any reason (yet) to upgrade from the Strano rear bar, it feels pretty good to me paired with a big front bar.

With the alignment fixed, and the roasted 285s replaced now with brand new fresh 305s, I'm excited to get some runs this weekend. Unfortunately it looks like those runs will be wet runs.

 

[jpaulson]

Do the konis feel like they have enough rebound? I am figuring I will have to run them near full stiff in front. I already run them 1/2 to 3/4 turn from full stiff in FS trim, but I am over compensating for overall lack of roll resistance. After driving Otis' Camaro some last year, I had a hard time going back to my rolley polley boat. Are you using 1 3/8 front bar or 1 1/2?

 

[SteveW]

@jpaulson, welcome to the party! I'm planning to be out at PIR South for OR Region the first weekend of March so, see you there. The BCA weekend this month is just too early for me but if it's snowing then I'll bring up the Subie Outback, haha.

Nice list of parts and glad to see the bolt upgrade with the diff inserts. Upgraded bolts for the inserts are a must!

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