Wing on the Tail

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PostPosted: Sun Jun 10, 2018 2:50 pm
https://www.flickr.com/photos/162453992 ... res/24kN94

I did a test day Friday and had this tail on my freshly built Gen3.

What do you think?
Mick Robinson

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PostPosted: Sun Jun 10, 2018 2:53 pm
https://www.flickr.com/photos/162453992 ... res/33erWF
https://www.flickr.com/photos/162453992 ... res/ma6J66
Another view
Mick Robinson

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PostPosted: Sun Jun 10, 2018 6:25 pm
I bet Steve Saleen likes it!
It looks cool but if a simple wicker balanced the aero I'd rather have that.
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PostPosted: Sun Jun 10, 2018 8:32 pm
Mick -
I like it a LOT. A better mount than the one I've done on my modified Renault (it is now a 2.0L).
Are those taillights "real" or stick-ons? Looking for a good set to go nights.

Is this setup for track days, SPU, or just "testing" configurations?

Cheers - Jim
When I used to fly, I was called an AVIATOR.
Now, I race cars. So, am I called a PAVIATOR?

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PostPosted: Mon Jun 11, 2018 9:33 am
I have had the tail for a long time. It came on a car I got from Dubai. This is the tail modification they did. The entire top of the tail is strengthened with aluminium plates and fiberglass on the underside. That added a lot of weight to the tail. The lights are decals.
I was breaking in a new Gen3 kit so I thought I would use the tail for the practice day. The Sebring short course does not have any high speed corners so I didn’t really get to feel how the wing worked and I don’t have data in that car to do back to back tests. The wing has minimal camber and was used for cosmetic reasons in Dubai.
I think it looks good. However having run some FE’s the wings are very expensive and could add hundreds of dollars to crash repair costs. The nose would have to have some kind of aero devices to offset the down force of the wing. The car would also be slower with the aero drag.
I got a lot of positive feedback on the wing from people at the test day.
Mick Robinson
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PostPosted: Wed Jun 13, 2018 9:01 pm
Needs a bigger wing!

You will definitely need some help in the front. Not visible in the photo, but the aluminum nose pan was replaced by a fiberglass splitter from a sports racer. We originally didn't have the wing, but the downforce was so strong on the front, we had to add a rear wing to get it balanced. Live and learn!



ImageIMG_1288 by bobsrf51, on Flickr
Bob Breton - SRF 51 - San Francisco Region

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PostPosted: Fri Jun 15, 2018 1:34 pm
Wow Bob, that body has been altered in a neat way! Must be the 25 Hour car. I like the body behind the front wheels the front splitter and the tail. Is the oil cooler in the area behind the front wheels before the vent? How did the car do without the areo? Are there any engine mods? How do the lap times compare against a Gen3, apples to oranges?
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PostPosted: Fri Jun 15, 2018 8:22 pm
Yeh, it's the 25 Hour car. Laps times with Toyo tires are comparable to a stock Gen3 with Hoosiers. Slight loss of top end, but better mid-corner speed. Also, the car has been stretched about 6 inches to accomodate a taller driver since the fuel cell is larger (12 gal. if I recall correctly, and the stock fiberglass seat has been moved forward and modified to cover the larger fuel tank.. All the bodywork pieces have been customized to accomodate the rear wing (we flattened out in earlier iterations which, with a wicker bill, actually had downforce as the stock tail actually generates lift!). The oil cooler is in the stock location; there's a vertical slot visible between the car number and front wheel for air flow to the cooler. The center section was extended to the rear of the front wheels and the nose modified rear of the centerline of the front wheels to eliminate the angle rear section and mount over the extended center pod. Bodywork is also extremely light, with a separate nose with lights for night driving. I was surprised that the stretched chassis really didn't negatively affect the overall balance of the car. Other than some minor shock bump changes, we ran pretty much what we had the prior year with the stock chassis.

The one area that needs work is the alternator, which can't keep up with all the lights (would definitely like more lights), but finding a substitute for the G3 alternator has been the main challenge.

As a precaution, we added a second fuel pump in the fuel cell with the driver able to switch on demand. Also an AIM Steering Wheel 3 with EVO4S (great at night and additional safety of the configurable alarms).

We also have a completely different shock / spring package (not Penske's) that are double-adjustable and much more balanced front/rear springs to better match the weight distribution and aero (BTW, the G3 could definitely use a stiffer spring package as well as the current grip level and weight distribution is significantly different from the original Ford package. The shocks also have more suspension travel than the Penske's, again, another issue we ran into when trying to lower the car to take greater advantage of the front splitter. Just have to keep the drivers from going over the curbs as it definitely grinds up the front splitter.

We are running the stock engine package; this is the second enduro for the car and last time we checked the hour meter the engine has 57 hours on it (and still feels strong.) The simplest way would be to turn up the rev limiter, but that has longevity risks (though I expect and extra 500-750 RPM would not be that drastic).

Running the Hoosiers would definitely improve the speed over the Toyo's by up to a couple of seconds a lap, but we can run a full 25 hours on less than 2 sets of R888R (and still have plenty of tire left at the end.) Based on our Hoosier wear experience, we projected we would need at least 6 to 8 sets, so adding $6-8k to the budget was not very enticing.
Bob Breton - SRF 51 - San Francisco Region
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PostPosted: Tue Aug 14, 2018 4:59 am
Bob -
I have a few questions regarding the 6 inches added to the chassis:

1. Can you recall where on the chassis? Aft of seat, forward of dash, or?
2. Larger fuel cell - a wedge - or "box"?
3. Do you recall/can you share the shocks you used?
4. Any details on the lights? LEDs, HIDs, etc?
5. Any other weight/balance mods, e.g. move battery, fire bottle?
6. Most importantly - Notice any handling differences you could attribute to the longer wheelbase?

The center section was extended to the rear of the front wheels and the nose modified rear of the centerline of the front wheels to eliminate the angle rear section and mount over the extended center pod.


Any consideration given to enclosing the rear wheels like a Bobsey/other SRs? With such long life on the Toyos, seems very do-able.

PM if you like. I'm considering/looking at some "winter work" for my SPU. At 98 inch wheelbase (92+6) some other options open up for used body parts/molds.
When I used to fly, I was called an AVIATOR.
Now, I race cars. So, am I called a PAVIATOR?
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PostPosted: Tue Aug 14, 2018 9:56 am
The chassis was lengthened in the center section to allow for a longer-legged driver and compensate for the 3-4" lost with the fuel cell. I I don't recall exactly where, but it was sectioned behind the main bulkhead near the dash area.

The fuel cell is a wedge in the same general dimensions as the original, with additional depth to provide greater fuel capacity (~12 gallons). An additional in-tank fuel pump was added as a fail=safe, since this would not serviceable in enduro conditions if one failed. Dash switch provided the ability to toggle to the backup pump as needed.

I believe the shocks were Stax, double adjustable for both bounce and rebound. Springs were changed to a significantly higher rate to manage the body roll and balance the front splitter downforce with the rear wing. The shock body is shorter than the Penske, so there was more wheel travel available before hitting the bump stops (anyone that ever ran the Penske's without shortening the original bump stops learned that the hard way!)

The main lighting system is HID. We added addition LED's for side coverage, but ran out of alternator capacity. Definitely needs more lighting so Ric Heer has been able to source a 100amp alternator that fits the stock location (still to be tested, but looks promising). Getting more lighting is my #1 wishlist item that would definitely improve nighttime performance (and driver comfort!)

There were other frame mods to the sidepods due to bodywork changes, (along with very light bodywork, but no significant efforts to move weight forward.) I don't recall that the chassis lengthening had any significant impact on handling; Thunderhill is a pretty fast track without any real 2nd gear corners. We learned some lessons on shock settings that improved the handling and reduced some of the wear on the fiberglass front splitter from dragging under compression.

Bodywork is always a subject of discussion and I expect Ric will have more ideas in the future to smooth things out and reduce frontal area. Since TH is also not a 5th gear track, it's less of an issue for aero than someplace like Daytona.

Would love to be able to use the Hoosier's, but the lifespan, extra pit stops and expense didn't pencil out. Keeping the car running, and reducing pit stop times, are the biggest opportunities to advance finishing position (though I'd like to have a few more RPM to work with before running into the d*mn rev limiter that seems to be designed to kick in at the worst point on every corner at TH!)
Bob Breton - SRF 51 - San Francisco Region
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