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Vintage RX-7 GTU @ Daytona Continental Race Nov05

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Vintage RX-7 GTU @ Daytona Continental Race Nov05

Old 11-25-05, 08:42 AM
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Vintage RX-7 GTU @ Daytona Continental Race Nov05

Daytona Continental Races Nov 2005 by Tom Turner

Driving at Daytona is something that I have always wanted to do since I was a young man, and I decided that this was going to be the year that I was going to drive the full 3.7 mile circuit they use for the Rolex 24 hour race. The Historic Sportscar Racing’s Daytona Continental Races are their year end event, and it usually has a pretty good turnout, about 280 race cars.

Brett Whisenant, George Kelley and myself left Huntsville about 10:30 pm Tuesday night 8 November and headed south for the 12 hour drive to Daytona. The big turbo diesel Ford pickup did well, but it just didn’t have the interior room that the Ford van had, making it more crowded in the cab for a long haul like this. But, the turbo towed the big trailer 10mph faster than the old N/A diesel van did, so we got there much faster. We rolled into the track about noon Wednesday and got inline at registration, then had to wait another hour or so before track security would let us into the paddock. They were only letting a handful of truck/trailers in at a time so that their would not be too big a jam in the paddock. The infield garage area had been completely rebuilt over last winter, with nice new $200 rental garages for the higher budget teams, and many new buildings like huge meeting rooms for the drivers meetings and a nice winners circle. It was such a big change that even experienced Daytona racers had a hard time finding their way around the new facilities. We set up our awning, got our tech stickers and headed for our hotel. No camping was allowed in the paddocks; at 6:30pm every night they locked up the high barb wire topped fences around the paddocks and turned loose the K-9 guard dogs. Probably a lesson learned from old stock car racers tampering with their competitors Track security is really tight here, tighter than any other track I have been too. They had some RV parking areas inside the track at the rate of $300 for the weekend. Since it was the tourist off season, a hotel on the beach was cheaper than their RV fees, so that’s the route we took. Even for the off season, the weather was great for the 5 days we were down there, with low 80’s during the sunny days and 60 degree temps at night.

Thursday morning we had our test day driver’s meeting, and they told us small bore car drivers over and over to stay in the low groove on the high bank and let the big bore cars have the high lanes. My car was very nervous on the high bank parts of the track when I went out for the first test session. As the car was mashed down on the high bank turns, the bumps made it want to jump from left to right about 3 feet at a time. I quickly got a lot more respect for the racers who run this track at much higher speeds than me. That first day it was so scary that I did a lot of praying asking God to protect me from injury. On this first session out, I lost it in the chicane on the back straight, and did some off roading in the sand at 90 mph. It ended up cracking a triangular 12” section off the bottom of the right front fender. George Kelley formed a piece of sheet aluminum to match and riveted it on to replace the missing fiberglas section. His emergency race track repair held up fine the rest of the weekend.

Brett W and I started going over the steering, and we found a few things that were loose. We found 1 bolt loose that attached the RF lower strut to the lower control arm, probably the same type bolt that failed on Dr Lovelady’s Mazda at the Crow Mountain hillclimb. Maybe the Crow shook my bolt loose too. Fortunately I had it safety wired, so it did not come all the way out. We found the steering idler arm was a little worn, so we replaced it with a new one ordered overnight from Advance Auto Parts. Finally the thing that made the biggest difference improving high speed stability was changing the toe-in from zero to 1/8” toe-in.

Another thing we learned about Daytona was that the car would run out of gas with ¼ tank left, because the fuel pickup was in the normal road race location in the left rear of the tank. That was good for all road race tracks that run clockwise, but not good for Daytona which ran counter-clockwise. Instead of changing the fuel pickup for this one race weekend, we just kept the tank filled higher than normal so that it would not run less than 3/8 tank during the main races.

I got a little more comfortable with more driving experience in the big bowl of the high bank. By Friday afternoon qualifying, I was running 2:08 lap time. I knew I could run faster, but I couldn’t get a good clean lap before I ran low on fuel in that short session. We had 60 cars on the track each time our group went out, and the faster cars were mixed with the slower cars, making me watch my mirrors constantly on the high banks so that I wouldn’t get rear ended. Tom King (Porsche) qualified first, Brad Blum (Porsche) qualified second, and O’Brien III (Porsche) qualified third, our RX-7 Mazda was fourth out of the 8 cars in our under 3 litre no turbo GTU class. After qualifying, we packed up and headed into town, getting fresh seafood and pitchers of beer at an open air dockside café I know down there. After we were lubricated, we then went down to the strip and rented go karts. My crew complained that I was driving too aggressively, but I looked at it as a chance to hone my passing skills for the final 2005 points race at 9:30 the next morning.

Saturday morning we woke up a little sore with some new bruises from last nights unpadded kart action. The pace lap of our race was the first time that I actually went slow (about 60 mph) on the high bank. Those old stories about having to run 100 mph just to stay up on the high bank had a bit of truth to them; 100 mph felt just like an easy 60 mph cruise on the Parkway, the car would stay level in the turns at 100. But on our slow 60mph pace lap, my car kept wanting to turn down off the track; it felt like I was going to fall over. When the green flag fell I got a great start and passed several cars by moving down really low onto the grass at the edge of the tri-oval. I passed Tom King and took first in class as we were coming out of the International Horseshoe turn. Traffic was packed tight going thru the road course section in the infield; all the cars were really bunched up. The only way to protect my position was to fight to hold the inside of each turn. Tom King was right on my tail in turn 6, and lightly bumped me. It only slightly upset my car, and I was able to come out of the turn pretty strong, and started opening up a growing lead. Once the cars started stretching out during the race, it felt much more comfortable than the practice sessions, because I didn’t have any faster cars going by me; I didn’t have to stay low on the oval. My old Mazda was running really strong, hitting 160 mph without a draft. I don’t know how fast it was running with a draft, because I couldn’t make my eyes look at the gauges when drafting at that speed. A bad wreck near the end of the race brought out the pace car, and Tom King caught backup at the green flag/white flag re-start. He challenged me in the infield, but I opened up a lead on the high bank, and took the GTU class win. With our race over that morning, we had the afternoon off, and headed for the beach, a treat for us compared to our usual race weekends. Saturday night HSR had their year end awards banquet. Unlike their usual Saturday night parties with free drinks, this one had a cash bar, so every one seemed to clear out pretty fast once diner and the awards were over.

One thing that we worked hard to learn all weekend was setting the tire pressures, because they would grow differently on this banked track. Getting them to end up being correct when hot was a challenge before each outing. Brett W. kept a close eye on them, and he did a very good job of predicting the right pressures for my races. Since Saturday was the end of the 2005 race season, HSR made the Sunday race the first points paying event of the 2006 race season, something unusual for HSR. We raced again at 8:30am Sunday morning, and I got a good start again, pulling clear of the rest of the GTU cars in my class. I got into a good race with a late model Grand Am BMW M3 running in a higher class; we were very closely matched. I finally got a pass on him in the infield, but blew it in the back of the track when I went into chicane too fast, sliding sideways at a 100. The BMW went back by me and staid ahead of me for the rest of the race. I pulled up beside him on the cool down lap and gave him a big thumbs up. After the race, he found me in the paddock, and we thanked each other for the close, clean race we had. Close competition like that is why we race, and even though he beat me it was still a thrill to be in the fight. Even though I couldn’t beat the M3, I still got the GTU class win Sunday morning, turning a 2:04 lap time. To put this lap time in perspective, my 26 year old RX-7 was 3 seconds a lap faster than the new Goldin Brothers RX-8 qualified at the Daytona Rolex 24 hour race this spring.

We packed up, and headed back home, making a safe trip back to Huntsville, 5 days after we left home. This wrapped up my 2005 racing season, my most active and best ever season. I would like to thank Brett Whisenant for crewing at every one of my races this year, and George Kelley for being with me for our 11th racing season together.

Last edited by speedturn; 11-25-05 at 08:46 AM.
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Old 11-25-05, 11:27 AM
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Smile

Any pictures???
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Old 11-25-05, 12:42 PM
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I haven't yet assimilated all the photos from this weekend. It may take awhile to gather photos from everyone. Their are other picutes of my car around on this website.
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Old 11-25-05, 02:14 PM
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Well,,, pics.... Thank you for taking the time to do such a nice write-up so that we can live vicariously through your amazing experience. Can you describe the car that you were driving, or is it one that I can find in your other posts?
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Old 11-25-05, 02:21 PM
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Found a picture of your car from the entants list at Crow MNountain. Assuming I still have a good job next year, I am thinking an old FB GTU car, a "real" one would be the next car I would like to build/restore. Alternately I may do a sports racer based off a FM car. Anyway, I'd love a link to more pictures, specs, and history of your efforts, and your car. Thanks so much, Carl

BTW, are you nea, and or ever go to Downing?
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Old 11-25-05, 11:35 PM
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sounds like a great weekend. Carl if your looking for a real IMSA GTU car I know of one for sale, but it is a second gen.
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Old 11-26-05, 09:06 AM
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1979 SA22 full tub chassis - still has Mazda steel inner fenders, floor, firewall, roof, rear chassis. Very stout cage with 1-3/4 x .095 DOM tubing

IMSA MkI fiberglas nose, fenders, hood, lexan windows - 2040 pounds without me.

Wilwood rotors & calipers, Tilton dual master cyl, all stainless plumbing; no Jap here.

13B PP motor built by me. Housings ported by Nick at Rotary Reliability & Racing. Honest 300 rwhp. No turbos allowed, no FI allowed, so big Weber downdraft 2 barrel, very heavily massaged, opened up as big as the castings will allow. My handmade airbox. ISC stainless steel header, and my handmade 89" primary pipes + my handmade collector under rear axle. Flat torque curve from 6000 to 8500 rpm. Engine drinks 1 gallon per 4 minutes at most road race tracks. It was thirstier at Daytona

Quartermaster 7" dual disc clutch + flywheel. Magnesium cased G-Force GF-5R dog ring gear box with long input shaft to set the big tranny farther back for better weight distribution. Tranny made for V-8 drag racing, the faster you upshift the smoother it gets, faster upshifts than any other box I've shifted. Downside of tranny is high cost; adapters + tranny + custom driveshaft cost $7000, but it NEVER breaks down in 3 years of road racing. 2:1 first gear, tight ratios, 1:1 high efficency 5th gear. It sounds really sweet ripping thru those close ratio gears going up a straight.

10" wide 3 piece rims with Goodyear 23x10.5-15 slicks. The metric equivalent would be about 305/30-15.

All spherical bearing suspension, G-Force goodies front & rear, Bilstein shocks. Simple strut up front, and solid axle in the back. Most road race tracks are pretty smooth, and a solid axle rear end is not a liability.

4.08, 4.44, 4,88, and 5.13 chunks loaded with good clutch LSD's. Ratio used depends on track I'm running. I've got gears and I'm not affraid to use them

Great cooling system, alum radiator + 2 oil coolers, hand built very efficient ducting, no air wasted in the nose.

I've been running this car since 1995, and have been very succesful the last few years. If took me a few years to learn how to make one run up front reliably.
Attached Thumbnails Vintage RX-7 GTU @ Daytona Continental Race Nov05-04.jpg  
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Old 12-02-05, 09:11 AM
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Daytona Photos

Finally got a few Daytona photos. One of me on the high bank, one in the infield with a bunch of my Porsche compeitors, and one BMW M1 GTO car behind me. One of me and crew chief George Kelley.
Attached Thumbnails Vintage RX-7 GTU @ Daytona Continental Race Nov05-highbank-mr.jpg   Vintage RX-7 GTU @ Daytona Continental Race Nov05-infield-lr.jpg   Vintage RX-7 GTU @ Daytona Continental Race Nov05-daytona-winners-lr.jpg  
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Old 12-02-05, 09:45 AM
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Way to go Tom. Beautiful car, really represents the rotary.
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Old 12-02-05, 10:02 AM
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Congrats, that looks and sounds really well sorted. Plus, class wins!
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Old 12-06-05, 02:31 AM
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I would really like to see some engine pics of you have them. I bet if you ran this carb you could use 1 gallon every two minutes. Ever seen one of these? its an extremely modded 51 IDA that has had the venturies removed and setup with annular discharge. I wonder if it would be allowed in your class. They were banned years ago from most scca classes for abviouse reasons.

CJG
Attached Thumbnails Vintage RX-7 GTU @ Daytona Continental Race Nov05-dscn1800.jpg   Vintage RX-7 GTU @ Daytona Continental Race Nov05-dscn1801.jpg   Vintage RX-7 GTU @ Daytona Continental Race Nov05-dscn1802.jpg  
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Old 12-10-05, 04:07 PM
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yes the annular discharge venturies were banned.

The IDA booster venturi was not the best design in the world; I now run better, bigger (yet legal) booster venturies.
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Old 12-11-05, 09:15 PM
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Tom if Id have known you were comming down here Id have offered to take off work and crew for you man. Kudos on the victories. Next time you plan to run in this neck of the woods, let me know.
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Old 12-11-05, 11:28 PM
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That is a sexy car... Especially while seeing Porsche's behind it. This coming from a Porsche fan.
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Old 12-16-05, 12:16 AM
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G force trans?

Really interested in the specs for the G force trans.
Replacing the T2 trans in a GTU 20b
Do you have the build sheet?
What is the weight of the trans.
Which shifter ....etc...
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Old 12-16-05, 07:22 AM
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Yes, beautiful car. I believe you had pics of the motor build posted a while back as I recall. First class all the way. Surprisingly light considering all the steel fender lines and such.
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Old 12-16-05, 10:14 AM
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I use the GF-5R transmission with the Long Machine and Tool company shifter. The R stands for roll over, meaning the tranny is rolled on its side with the shift linkage on top, giving a little more clearance underneath. I don't really know if that is necessary though; I have not had any clearance problems underneath. The rollover makes the tranny wider, and puts the countershaft and gears more over on the drivers side. I relocated engine/tranny to the car centerline, and had to widen my tunnel a little. I do have the build sheet. Here is their website:

http://www.g-forcetransmissions.com/tran_gf5r.asp

This tranny is built for V-8 levels of torque, and it is heavy and strong. Even with the light magnesium case, the much larger gears and shafts make it weigh almost 50 pounds more than a 1st gen RX-7 tranny; with RX-3 bell housing and adapter, it weighs in at 120 pounds versus the Mazda tranny weighing 70 pounds. The weight is low and in the center of the car, so it does not hurt handling. Attached is a photo comparing a heavy duty Mazda factory racing transmission input shaft with the input shaft from the G-Force tranny - big difference isn't there! The longer input shaft on the G-Force tranny sets the tranny weight much farther back in the chassis for more weight on the rear wheels. This tranny uses the Chevy fine spline input shaft, and several clutches are available from Tilton and Quartermaster. G-Force turns down the pilot bearing size to match the Mazda pilot bearing diameter.

Carl: I should have made a post letting people know I was coming down to Daytona. I would be great to meet you in person after these many years on the internet. Make Plans to be at the huge Walter Mitty race at Road Atlanta the last weekend in April 2006. Japanese racecars will be the featured marques at this event.
Attached Thumbnails Vintage RX-7 GTU @ Daytona Continental Race Nov05-input_shaft_compare.jpg  

Last edited by speedturn; 12-16-05 at 10:19 AM.
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Old 12-17-05, 10:53 AM
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G force vs Jerico

Did you consider the Jerico 5 speed? Seems to be plenty strong and some 15 pounds lighter.
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Old 12-17-05, 02:51 PM
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A buddy of mine runs the Jerico 5 speed in his GT-3 Mazda. The Jerico 5 speed is very similar to this G-Force gear box, it is a very fine and heavy duty unit. The reason I chose this particular G-Force is that I got a very good deal on it. It only had a few practice laps on it when the driver, Richard Sneed, totaled his GTU Mazda RX-7 at a Sebring HSR vintage race about 3 years ago. I pulled the almost new GF-5R box from the crashed chassis myself, and I also got the RX-3 bell housing and the trans adapter spool and the light flywheel, 7-1/4" dual disc clutch, and the hardened big driveshaft yoke, and the Long shifter and the trans cooler and electric trans oil pump for $5500. If bought brand new, all these parts would cost way over $7000. It only had a few laps on it so I figure it was a pretty good deal. It has never broke during a race. I used to DNF frequently with Mazda transmissions, and now I am always on the podium, even with 3 seasons of use.

If you are buying new, the price is going to be about the same for both boxes, and the amount of fab work to put it in will be about the same, either one will be a good gear box to use.

Last edited by speedturn; 12-17-05 at 02:53 PM.
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Old 02-03-06, 08:17 PM
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Yes, please plan to be at the Mitty with that car - I'd love to see it in person.

I haven't officially announced it yet, but Mazda has signed on to be the Presenting Sponsor for the Classic Motorsports Mitty at Road Atlanta April 28-30.

The theme is "The Sports Cars of Japan" to pay tribute to the Japanese cars that rocked the motorsports world. As you may know, the RX-7 holds the record for the most IMSA wins of any car model ever made. We are expecting at least 1,000 Japanese cars in the infield and I'd like to see RX-7's of all generations show up to support the rotory. Mazda will bringing out several famous IMSA GTU, GTO, GTP and LMP cars for display and for racing. Additionally, Jim Downing and other famous Mazda racing legends will be on hand for autographs and seminars.

We have commissioned world famous motorsports artist Hector Cadematori to create a piece of original art depicting the Racing Beat #7 and #17 RX-7's at Road Atlanta as they took the IMSA GTU championship at Road Atlanta in 1980. The new poster art will be distributed soon.

This event has grown by leaps and bounds since Classic Motorsports magazine has been involved and it will continue to grow even more with Mazda behind it.

I really hope to have a chance to meet everyone as this will be an amazing gathering. For those of you who haven't been to the Mitty or don't know anything about it, check out the following links to see what kind of cars were on track last year:

http://dvwphoto.smugmug.com/keyword/walter%20mitty/1

http://www.motorsport.com/photos/sel...hard_Sloop&O=0

In addition to those cars, we'll have the KUMHO MINI Coopers and new Lotus Elises available for participants to autocross. Keep an eye on the main page of ClassicMotorsports.net as the next few days you will find a link to a Web site dedicated to the Mitty.

Spread the word around this and other rotary forums - it's going to be amazing.

Regards,
Bill MacDonald
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Old 02-05-06, 10:21 PM
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I definitely plan to be at the Mitty and I am very happy that Mazda is going to sponsor this major race.

I have been running the Mitty since 1997, and I have won the GTU class there 4 times now. God willing, I will have another good year in 2006.

I am very thankful of the fine parts support by Mazdaspeed Motorsports for all these years.

Tom Turner
Huntsville, AL
1979 Mazda RX-7 GTU #79

Last edited by speedturn; 02-05-06 at 10:23 PM.
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