Thunder Roadster vs RUSH SR

[TR001]

This looks like an awesome car. I have a Thunder Roadster and I'm debating a transition. From what I can tell:

- both are purpose built race cars
- the TR I have has the 1340cc Hayabusa with fuel injection
- the SR weighs less
- the SR has a more sophisticated suspension
- the SR has paddle shifting
- the TR doesn't use a chain
- the TR is 10k+ less expensive

A few questions:

- does the paddle shift system rev match?
- is the throttle mechanical or drive-by-wire?
- who manufactures the paddle shift system in the SR?
- what is a respectable lap time in a SR at Sonoma?
- does the SR use a limited slip differential?
- what is the rear differential ratio used?
- what are some other advantages over a TR?

Thanks for your time,

Gary Keefe

 

[David Hosie]

Gary,

The paddle shift system does not rev match it doesn't need to due to the sequential dog box. The system gives a flat foot full throttle up shift and auto blips on the down shifts so you don't touch the clutch.

All new builds are now throttle by wire.

The paddle shift system is our own design, and uses our on GCU.

No Idea about Sonoma but at Sebring, Homes ted, Roebling, MSR Houston, AMP and VIR we are right on the same lap times as a 718 GT4 Clubsport.

The SR has a 12 plate adjustable Salisbury style diff with 1-1/2 & 2 diff ramps. The plates, 6 per side can be set up for 5, 3, 1 contact faces giving 100%, 60% & 20% friction.

Standard final drive ratio = 2.933:1 options are 2.75:1 & 3.143:1

The other primary advantages would be operational cost and on track performance.

Please don't hesitate to reach out to Cale if you need any more information.

I believe we also have a dealer close to you if you want to visit with them. They just got their first car.

Their link here is below and their website is https://lateentrymotorsports.com/

Late Entry Motorsports

rush.sr

You will get a good idea of the speed of the paddle shift system from this link. Gear shifts happen in 65ms!

MSR Houston onboard!

This weekend was amazing! Ended up with an overall 1st and 2nd after starting from the back! NASA TX ran an amazing event and we cant wait for the next one at MSR Creson. Really looking forward to having 20+ SR's on track for the Battle of the South, let's dominate the weekend!

rush.sr

 

[Tom Kersting]

Gary,
I’m in STL and have one on order, should be ready early in track season. Will be at OIR several times this year. I also know of 2 other cars from STL guys on order and we’re working on getting others interested.

The dealer linked above also has several cars on order from what I understand. I’m guessing our area will have lots of these cars over the next 12 months.

 

[jlaughman22]

The guys at Fresno power sports ran a 1:45 at Sonoma but I think they got that down to a 1:43-44 look at st2 class

 

[David Hosie]

Gary,
I’m in STL and have one on order, should be ready early in track season. Will be at OIR several times this year. I also know of 2 other cars from STL guys on order and we’re working on getting others interested.

The dealer linked above also has several cars on order from what I understand. I’m guessing our area will have lots of these cars over the next 12 months.

We have a pile of cars heading that way, plus if you look at our race schedule we will have a big crowd of hopefully 20+ cars at Ozarks in the fall!

 

[TR001]

Thanks for the replies.

 

[Michael Schneider]

This looks like an awesome car. I have a Thunder Roadster and I'm debating a transition. From what I can tell:

- both are purpose built race cars
- the TR I have has the 1340cc Hayabusa with fuel injection
- the SR weighs less
- the SR has a more sophisticated suspension
- the SR has paddle shifting
- the TR doesn't use a chain
- the TR is 10k+ less expensive

A few questions:

- does the paddle shift system rev match?
- is the throttle mechanical or drive-by-wire?
- who manufactures the paddle shift system in the SR?
- what is a respectable lap time in a SR at Sonoma?
- does the SR use a limited slip differential?
- what is the rear differential ratio used?
- what are some other advantages over a TR?

Thanks for your time,

Gary Keefe

Jlaughman is correct. also, I have spoken to a few TR guys and they mentioned that the busa is carburated. My times are all on the factory 100TW Nankang AR1 street tires as opposed to the Hoosier slicks ran on the TR's.