Unfortunately, no race at RA . . . wish there was.

We didn't actually have any 'redline rules' as Mark jokes . . . the problem was, the stock motor would NOT achieve redline in either 4, 5 or (obviously) 6th gear. The aerodynamics made the engine 'hit the wall' before redline. We decided to short shift at 6k to 'save the motor' . . . it worked because we finished the race. Even with the short shifts, we were still 'wringing it's neck'.

It is a testament to the engineering and the way the engine is built that it ran with no hiccups.

Incidently, the race motor suffered a 'holed' piston. There were rumors flying around the pits about bad race gas. No one knows how fresh the stuff was, but we do know there were quite a few cars that suffered the same fate as us.

Randy

ps: The race motor would hit redline in 4th and 5th without effort. We sure missed not having it . . .

 

Are you required to run the Sunoco gas that is supplied at most of these tracks? I know we have a lot of problems with it in the karting engines. The 110 is better than the 112 for us. I no longer run this fuel and went back to using Klotz #408 113 octane.

 

Randy, When I last raced my SSC Cooper S at Daytona, with a stock engine, (50 mm restrictor and 3050 lbs) I had no problem hitting reline in 5th and was damm close in 6th. I was shifting into 6th at the end of nascar 4 right at the start of the bleachers. at the starter stand I was indicating 130 +. Looking forward to the next race there as an SSB car.

 

Dave

Interesting you could get up to 130+, I could not get past 120 at the start/finish even if I held my breath!! I watched your videos several times to get an idea of the track layout but as you know, there is nothing like doing it live. Great track, the banking is hard to describe. Continued sucess with your SSC MINI!!

And yes we have to run the Sunoco

 

Good Afternoon,

I also run my 06 mini S in SSC and my mini was at 130+ as well. I ran mine just like Dave's Mini with the restrictor and at 3050 weigh and bone stock even down to the exhaust.
I think you may have something wrong with that motor??? I am the current track record holder for Daytona in SSC with a 2:27. I am really looking forward to the May National now that we no longer have the restrictor and only weight 2750.
Jill

 

Very strange stuff . . . honest to god . . . flat out <120 at the tri-oval with the stock motor. Best RPM's I ever saw was 6200 in 4th and 6000 in 5th. We were turning 2:26's.

It is certainly possible we were a lot faster in the infield and that much slower on the banks.

My Spec Mini racer has a 100 octane flash and normally a 15% pulley. We ran Daytona with the flash (no way to change it at the track) but NO pulley. I must now assume the 100 flash killed the top end.

Any thoughts on this would be appreciated.

The race motor was 130/132 at redline . . .

Randy

 

Randy,
Not sure what a 100 flash is??? What do you have for exhaust?? What suspension do you run?? stock??? Just wondering what the rules were compared to SSB in SCCA?

Jill

 

Jill:

100 Octane flash is a reprogram of the fuel / air / timing map of the engine's ECU to accept 100 octane fuel rather than 91 octane as delivered from the factory. In general . . . the timing will stay advanced to take advantage of the better fuel.

We don't run an exhaust that is at all similar to yours. No cat and the exhaust dumps out the side. Suspension geometry is stock w/ Koni shocks.

Grand Am is very restrictive . . . SSB is more so !

I do know this. . . it takes alot of HP to push a Mini to 130mph. We affectionately call it the 'flying brick'. The race motor did it . . . the stock motor didn't.

Randy

 

Randy, 130 sounds about right for top-end in 5th. That's about what we get at Mosport. When we shift in 6th it normally doesn't get any faster as that's as short as the straight line is (for us).

A few points to consider. Was that indicated in your aim or on the OE speedometer ? If from your aim, are you using the ECU signal or an aftermarket wheel speed sensor. If it's a sensor, are you sure the calibration is correct?

Also, please consider the diameter of the tires on indicated vs. actual. (for us it's on smaller 205/50R15 Toyos).

May be your mixture was on the rich side. Just a thought. Are you running a wide-band?

Alain L.

 

Correct . . . it was 130 at redline in 5th. 6th gear makes no difference. Even with the race motor, 130/132 was it. We just don't have enough power to push it through the air any faster.

Part of the problem is the gearing . . . almost a 1500 rpm drop on the 4th to 5th gear shift. 5th gear is too tall and 6th is just along for the ride.
The ratios are NFG for racing !

I am using the factory Speedo ... race tire size 225/45/17. I have not measured the diameter but I suspect it's pretty close to the original 17" factory rubber. As I recall the factory tires were '40' section height.
Anyway, the speed relationship with the race motor and stock motor won't change. The stock motor was slower by 15 MPH at terminal velocity.

If the SSB cars run 15 inch rubber . . . that could explain the 130mph with a stock motor at Daytona. 15's will spin faster indicating higher top speed. 17's will spin slower showing a lower top speed. Between the two we could be looking at 8% to 10% (??) and that is 10 / 15 MPH. I think this explains how an SSB can show the same top speed as the GA car. My GA car with the stock motor will NOT go 130mph.

Does that make sense to everyone??

Randy

 

the reasoning is sound, but I still think you were down on power.

doesn't MINI specify the car as having a 130mph top speed? I would think that one of the many magazine tests would have brought this up if it were off by 15 mph.

I'm thinking the ECU flash may be the issue. Did the ECU flash eliminate the feedback from the knock sensors?

Just out of curiosity, what kinds of top speeds were the other ST cars getting at Daytona?

 

Yellow . . .

That is a VERY interesting thought . . . stock ECU limited to 130mph. I don't think any of us ever considered that and I don't know if we even looked at it. It would also explain why Tony Nuzzo's cars were 5-6 seconds faster when he ran last year at Daytona. Frankly, that was puzzling us.

The other ST cars were passing us by at least 10-15 MPH on the banks. We could run with them in the tight short sections . . . not so on the high speed sections.

Lastly, the Koni shocks caused a ride height issue. We were at least an inch too tall and that added to the aerodynamic woes.

Thanks for the suggestion.

Randy

 

Glad to help. Maybe I can put my engineering degree to use after all!

(don't tell my boss I said that...he thinks I do engineering here!)

 

someone earlier brought up the idea of getting grand am to okay the use of GP parts. would the relatively smooth undertray of the GP allow for a higher top speed or just increased stability at a lower high speed?

i don't understand aero stuff well enough to answer this for myself... so i'm interested in hearing the smart people's opinion

 

Hey Randy
The stock tires for the S is 205/40/17. I think part of your problem would be your ride height. As you have said your moving a brick. The extra inch has to be a killer. I've hit 126-128 at Watkins and had the car run out of rpm hitting the limiter in the back straight @ 7100 rpm.
Can you guys use the under panels off the 06 GP. My GP compared to my 03 cut the winds at the Glen a lot better and the GP isn't lowered like my 03. What about the gas issue people were having?

 

No question ride height is part of the Aero problem. We are working with the shock people to solve this.
Not certain what the status of GP parts would be.

I am convinced that the top speed issue is more than just Aero because . . . if a stock SSB Mini can do 130 . . . we should be able to do more.

. . . a work in progress.

Randy

 

Hello Randy,

I think the reason you are not hitting redline has to do with the size of your tires,

Your actual tires 225/45/17 have a overall tire diameter of 24.97"

The factory 205/45x17 tire diameter is 24.26"

This is actually quite a difference, for your stock motor,
maybe not so much for your race motor.

Looks like you will have to change tire size or play with the final drive or gear ratios.

Victor

 

Thanks Victor . . . you saved me the trouble of measuring the tires.

Unfortunately, the tire size is set by Grand Am . . . no change allowed. Final drive is also set . . .

No help available from either of those solutions.

Randy

 

Randy, is this with the race motor?
If so, I have an idea what might be the problem, .. "might"

 

Yes. The stock motor was done at <120 . . .

Randy

 

Looking at the pictures is looks like an 8" wide wheel. The tire comes from the bead area goes out to the tread shoulder and then turns to the surface. With our racing this setup causes more tire growth at speed. What happens is the sidewall pulls straight at high speed this causes the tire to grow larger in diameter. The other individual running the 205 section tire is .78" narrower tread width. On the same width wheel this would be a big difference in circumfrence change. Where you are not allowed to change the gear ratios this could be a big reason you run out of speed. The ratio is changing because of the tire drastically basically hitting a multiple wall of aero drag and ratio changes.

Just something to check into with the Hoosier engineers.

 

The wheels look like OZ. They only make them in 7" wide in 4x100.

 

Alain:

That is correct. That is the max width wheel we are allowed to use. Don't ask me why . . . another GA rule mystery. On the plus side . . . the OZ's are light, cheap (relatively) and strong. . . .they bend and don't break.

Randy

 

I see I've missed a lot of discussion the past two days!

The good news is that the next race is over 2 months away... the bad, the track has plenty of long straights, and sweepers! Good luck guys.

 

Any more news on some in car footage gentlemen?