SCCA CAM-C Thread

[kz]

fair point, I run 3.15 gears.

You have to look at it through perspective of transmission ratios or more specifically a maximum speed in 2nd gear (which rear tire sizing affects same way the ring gear in the differential does) - you want to be ideally at 65 mph max.

Example above (15-17 PP GT with 3.73) has max 2nd gear speed at ~59 mph with tall stock 275/40R19 (27.3" diameter) tire. 315/30R18 is like 25.5" diameter, much shorter and will drop that max speed by quite a bit.

You probably know that but you do not want to be shifting to 3rd in faster sections and then trying to downshift after slowing down. Not more than once at least.

Sponsored

 

[CobaltFilly]

You have to look at it through perspective of transmission ratios or more specifically a maximum speed in 2nd gear (which rear tire sizing affects same way the ring gear in the differential does) - you want to be ideally at 65 mph max.

Example above (15-17 PP GT with 3.73) has max 2nd gear speed at ~59 mph with tall stock 275/40R19 (27.3" diameter) tire. 315/30R18 is like 25.5" diameter, much shorter.

My second gear in 3.15 on stock 17s is 71mph. So putting on 19x10s should lower is substantially yes?

max speed I hit out on that specific track was about 60 so it should be perfect.

 

[kz]

My second gear in 3.15 on stock 17s is 71mph. So putting on 19x10s should lower is substantially yes?

Depends - what tire size is that 71 mph with ?

You can calculate what your speed is going to be with whatever tire you're going to put on that 19x10" wheel.

 

[CobaltFilly]

Depends - what tire size is that 71 mph with ?

You can calculate what your speed is going to be with whatever tire you're going to put on that 19x10" wheel.

Stock 17x9.5s running 255 Michelin All Seasons.

Going to 19x10s running 285 Michelin 4PS or same size Firehawks until I upgrade to Miches.

 

[WItoTX]

Titanium splitter pucks in action. Because who doesn't love sparks???

 

[mavisky]

Titanium splitter pucks in action. Because who doesn't love sparks???

Love it.

I've been warned in grid many times that my car is falling apart because course workers saw sparks from underneath it. LOL.

 

[WItoTX]

So it turns out when you bleed the brakes, the one set of bleeders you forget to get all the brake fluid out of will make it look like you've had massive brake failure by the third run of the day. Note to future self...

 

[WItoTX]

We had the National Pro Solo this weekend in Beeville. All I can say is "stop the hop" kit my ass. I will be removing all the Steeda stop the hop kit from my car and going to anyone else.

Nothing like dropping from 1st to 4th because the car went into limp home mode. I made it back up to second Sunday, but man, absolute frustration when what ended up being the best session for power and grip turned into a mess of no power, no suspension, TC on....

 

[mavisky]

Hey guys, first event coming up this weekend with the Yok A052's. Anyone have a good starting pressure for these? I know that my Kumho's liked to live around the 28psi zone.

 

[kz]

We had the National Pro Solo this weekend in Beeville. All I can say is "stop the hop" kit my ass. I will be removing all the Steeda stop the hop kit from my car and going to anyone else.

Nothing like dropping from 1st to 4th because the car went into limp home mode. I made it back up to second Sunday, but man, absolute frustration when what ended up being the best session for power and grip turned into a mess of no power, no suspension, TC on....

I was looking at the results during the weekend - congrats ! Very nice job especially the competition was good (and index isn't IMO too favorable compared to CAM T).

I was in DFW right before this weekend and completely didn't think about but technically could come down and beg someone for a ride (especially that one local person from here was there with their car)

What was the limp mode caused by ? Was it Service Advancetrac ?
And why are you getting rid of stop the hop ?

 

[WItoTX]

I was looking at the results during the weekend - congrats ! Very nice job especially the competition was good (and index isn't IMO too favorable compared to CAM T).

I was in DFW right before this weekend and completely didn't think about but technically could come down and beg someone for a ride (especially that one local person from here was there with their car)

What was the limp mode caused by ? Was it Service Advancetrac ?
And why are you getting rid of stop the hop ?

Thank you!

The morning session was cold, so I did a burnout to heat the rears up. No issues. For the afternoon session, the air was still cold, but the pavement heated up pretty good under the sun. I think there was a lot more grip in the burnout box, and my tires were not as cold. My tire pressure guy said I had a wild wheel hop, but it's odd because in the car, I felt nothing unexpected, and reviewing video, there is no shake in the camera.

The issue was forscan showed an erratic left rear wheel speed sensor code, consistent with wheel hop. I tried restarting the car in between runs, and no luck, the car wouldn't clear the code. I was able to get TC to turn off on my last run, and made up a second on that run, with the service advance trak, ABS, and steering fault codes flashing at me. What is annoying, in post tech jail, the car cleared the code, and everything was working again. I think the car needed at least 30 seconds to reset itself.

If this was a tour event, I could have quickly scanned and cleared codes and been fine. But the Solo format...just gotta make it work.

Steeda's kit doesn't "stop the hop" during a standard burnout, I need something that will. I'm confident I had 1st place but for losing out on the best session of the weekend due to the wheel hop. I am very thankful more stuff didn't break.

 

[mavisky]

Having never run a pro-solo event, do they use any water in the burnout box like a drag strip?

Are you using the car's line-lock mode to do the burnout?

I've launched my car plenty hard on numerous occasions and even without the full "stop the hop" kit I've never been able to trigger wheel hop to my knowledge.

 

[kz]

Having never run a pro-solo event, do they use any water in the burnout box like a drag strip?

Nope, unless it rain but at that point your tire temperature doesn't matter.

Are you using the car's line-lock mode to do the burnout?

I do not.

I've launched my car plenty hard on numerous occasions and even without the full "stop the hop" kit I've never been able to trigger wheel hop to my knowledge.

I didn't either - I don't remember what stop the hop is but have the IRS bushing collars, sleeves, spherical bearings and those side braces. It doesn't hop, on a concrete though you have to get hard on the gas especially with sticky tires.

Hop you should easily feel in the car (shaking), outside it just might tire catching traction, not the actual hop I am thinking.

I would personally not ditch the Steeda bits just yet, there isn't much difference between them and BMR IMO, pick the color you like basically.

Also @WItoTX - even more impressive you did on Falkens in what is like a pretty cold event.

 

[WItoTX]

Nope, unless it rain but at that point your tire temperature doesn't matter.



I do not.



I didn't either - I don't remember what stop the hop is but have the IRS bushing collars, sleeves, spherical bearings and those side braces. It doesn't hop, on a concrete though you have to get hard on the gas especially with sticky tires.

Hop you should easily feel in the car (shaking), outside it just might tire catching traction, not the actual hop I am thinking.

I would personally not ditch the Steeda bits just yet, there isn't much difference between them and BMR IMO, pick the color you like basically.

Also @WItoTX - even more impressive you did on Falkens in what is like a pretty cold event.

Agree with all of this. I have all the same stuff as you, I just assume it's all part of the stop the hop. Truth be told, I think the only solution is new subframe bushings, something much stiffer, and I think the 2 piece drive shaft might be an issue. Fletcher here locally said power delivery became much smoother going to a 1 piece.

I haven't had this issue until this event. Since most say Beeville is similar to Lincoln in grip, I will just expect similar issues.

My Falkens had 4 runs on them prior to this event. Neuville had Nankangs in a similar scrub in condition, and so his cold temp grip was only going to be worse.

The CAMS PAX is pretty brutal this year. Glad to see CAMC is less brutal. Also, the Pro Solo is my favorite format by far. Love the tree start.

 

[kz]

The CAMS PAX is pretty brutal this year. Glad to see CAMC is less brutal. Also, the Pro Solo is my favorite format by far. Love the tree start.

Pro Solo is the best solo - unfortunately I can realistically do only two which are within 5 days of each other - Cleveland and Bristol. Oklahoma and Maine are not exactly reasonable options.

Sponsored