Has anyone had Keizer draw up wheel designs yet?

[Licklobster]

Asking before I recreate the wheel and take some measurements. If they've done a set already it would save everyone involved some time. The factory cast wheels arent particularly light at 13.5 and 11.1 pounds. Set of slepens will look really nice and probably save 10-12# of rotating weight.

 

[David Hosie]

The factory wheels are spec in all our series.

 

[Licklobster]

The factory wheels are spec in all our series.

The majority of Rush track time has nothing to do with your series.

 

[David Hosie]

The majority of Rush track time has nothing to do with your series.

I was simply letting you and others that may consider this know that wheels are not an open item in our series. Someone who buys a couple sets of third party wheels and then shows up to race but cant, their going to be pissed off at me not you, also believe that as the year progresses you will see that our series are an integral part of our brand. We are committed to building some of the strongest spec racing series in motorsport. I personally have a saying, a race car that is not raced its a toy. The RUSH was built to race and is already being raced in 4 series over 3 countries. By this time next year we will have 12 series and will only grow from there. I look forward to you receiving your car, I am certain that quickly you will find that the car is a platform where drivers can develop their skills on track and many will progress to racing in our series. As for saving rotating & unsprung mass we explored a lighter wheel, we would have saved about 3 lbs per wheel. There is way more to be found in tires. The AR-1 is a heavy tire being a steel belted radial. The benefit is also compounded by the radius of the tire vs the radius of the wheel. The good news is there is a large selection of 13" tires out there, that you wont have to pay to develop.

 

[Sam Reed]

Great point on the tires. I'm reading that the Hoosier R60A tires used on the SRF & Formula FF cars are 16lbs (front) and 18lbs (rear) in the same sizes used on the Rush SR. Nankang publishes 19lbs and 21lbs at the same sizes, meaning you can shave off the very same 3lbs per corner more cheaply and effectively by running another tire.

 

[David Hosie]

The rush was developed on Hoosier tires! Damn my name is in theirs! But they let us down big time! We had no option than to find another tire supplier. The AR-1 is the spec tire, we are developing slicks with them. The development tire was a xply and I can tell you is almost half the weight of the SRF radial! You just cant get them in quantity! Not now anyway! It was also a very forgiving tire! The R25 compound was superbly suited to the car. Nankang, stepped up to the plate when all Hoosier had to say was "Covid 19, explain to your customers why you cant deliver cars with tires', they will understand!! Those were the exact words! It may surprise you but that didn't fly too well with me. When tracking the RUSH there are a good number of tire choices. That said the AR-1s performance at $696 / set is hard to beat. Blair and a few others, have set some blistering laps at several tracks on the stock car and AR-1s! On a new set of slicks at the average track you may find 3-4 s, that's huge but a couple of sessions in the gap gets a lot narrower and a few sessions later may even reverse! That said don't forget the tire is actually the part of the car holding you to the track! How it performs tough, sometimes has a function on the steering wheel / seat link rod.

 

[Licklobster]

Agree on the tires, though at race speeds any savings from weight is lost from construction - belted radials are superior there (you can even see the gain on the dyno in an a-b test). I have a handful of things to test, including r25B bias slicks. I wish they made A7s an inch or two taller, will have to peruse the radial slick catalog. Also interested to see how much heat I can get into a tire (if I can make R7s work at all). We tune off of the tire pyrometer, after all.

Built it, and they will come - as they say.