Pro-7 Rule Changes

S

steve

Guest
This spring I found out that Toyo Tires is replacing the Proxes RA-1 with the R-888. I was told that the compound is the same but the construction is different. We should not have any problem getting RA-1s this year but will want to change the rules to also allow R-888s next year. I would recommend that we stay with the Toyos as they are a durable consistent tire.
I have also looked at other possible rule changes. I hoped to find changes that were cheap, durable and gave a significant improvement.
The people from California that I have talked to think that the rule changes they made helped keep interest up in the class. After careful consideration, I think we should make our rules similar to those of the California Sports Car Club Region of SCCA.
Basically the changes are to allow 205-60-13 tires, 7 x 13 inch wide wheels and a weight reduction to 2300 lbs. The minimum wheel weight is 13 lbs (Diamond $59, Circle $87). Lighter wheels (down to 9 lbs) are allowed with a weight penalty of 2 lbs for each pound of difference between the specified weight (13 lbs) and the actual wheel weight. I don't think this was intended as a performance advantage but was to allow cars with heavy drivers a way to be more competetive.
To help meet the weight reduction they allowed removal of door windows and regulators (11 lbs each), the heater core, blower fan and motor (? lbs), and the headlight, buckets and motors (22.5 lbs each). The battery is free and its location is behind the passanger seat. A 24 or 24F battery weighs 37 to 39 lbs. Braille makes the B14115, 11 lb, 8 oz ($150) that I have been told works fine with a big block V8. They even have the B106, 6 lbs, 6 oz ($140). Another possible place for weight redution is the rear window glass. Replacing it with 1/8 inch lexan ($126 materials + cut and form) saves 23 lbs. We could allow the plastic rear window instead of allowing wheels lighter than 13 lbs with a higher minimum weight - everyone could make the 2300 lbs and the total cost would be the same.
The new tires in combination with the weight reduction will result in a car with the same ability to accelerate, a slightly higher top speed and much improved cornering. (Going to taller wheels would require greater weight reduction or a diff change to avoid slight reduction in ability to accelerate.)
Additional possible mods:
4.10 diffenential ($558 + installation) - 4.9% improvement in acceleration - same top speed as now.
4.444 differential ($517 + installation) - 13.7 % improvement in acceleration - slight drop in top speed - ?rpm too high at Spokane?
ITA suspension ($1300)- I am not sure of the performance change - initially doesnt seem worth it to me.
Header/intake manifold/carb - might need brake upgrade - I have heard the headers don't last real well - I am afraid of this one - ususally when engine performance goes up, durability goes down.

Lets discuss this and try to reach a consensus. It will probably involve a meeting (2nd race PR?) or voting by email. I will make rule change proposals (or not) based on the consensus we reach.
 
Steve- Although just a novice I have tried to stay involved on Pro-7 rules as this will be my class when I finish my novice requirements.
I like the idea of a lighter battery and especially the relocation of the battery because I recently had my car corner weighted by a stock car friend. I could not belive the difference in corner weights and side to side percentages by just relocating the battery to the right rear passenger compartment area. I can see wider tires providing more grip but your suggestion still allows me to use up my remaining 185/60-13 RA-1's if desired. As far as removal of the windows and regulators, blower/heater core and headlight assemblies this seems like a great low budget (few hours labor) weight loss. I have yet to complete the calc's to see if I could reach 2300# but like the idea of helping out the heavier drivers as I'm pushing 270#. Thanks for taking the time to get prices and weights for this discussion. I will see you in Portland on 6/7.
 
Steve,
I also think R888 is a good replacement in CSM. I was just going to add it as a spec tire, then we all could use the RA-1's as rains for years to come and ware out "all" of RA-1s.

It seems that their are more Pro7's for sale and have been purchased lately. Boyd Campells car is coming out next weekend in novice. Pat Meehan's is for sale. I have Randle Kelley's here and its for sale. Some one bought the Tipton's Pro7.

I think I'd keep the rules the same except for the tires if you want to build the class. The rule changes you propose is just going to add costs to the class, and make the current "for sale" Pro7's less attractive to race because of the added cost if these rule get voted in.

Most of your suggested rule changes are legal in ITA and a few are not. So you won't even be able to run ITA as a second group like Bambi did at the last Seattle race.

If you want to go faster may I suggest ITA or Production.

The track record in Pro7 is in the 1:43's for qualifying & during the race by the way.
 
Jeff,
As I stated above, this discussion is an effort to reach a consensus. I will make rule change proposals (or not) based on the consensus the Pro-7 drivers reach.

The Pro-7 car minimum weight is currently 2400 lbs and it uses 7.3 inch wide tires and 5.5 inch wide rims. This is more weight on narrower tires and rims than a CR, SM or CSM.

The only rule changes I would recommend are the wheel, tire size and weight change I identified above. That would cost $236 for wheels, and $150 for the battery. Total $386 + tax,shipping & handling.
The weight reduction would be 100 lbs for 1 side window and regulator, 2 headlights, buckets and motors, the heater core and fan (assumed 18 lbs) and a 12 lb battery. Allowing replacement of the rear window with lexan, an even lighter battery, or removal of a second side window and regulator would allow heavier drivers a better chance to make the new minimum weight.

It is true that the car, as modified, would not be legal in ITA. It could still run a second race in Group 5 in EIP, Group 1 in SPM or Group 4 in GT-3. I realize the car would be even more uncompetitive in these classes than it is in ITA.

I have been doing what I can for the last few years to try to maintain/develop interest in
the Pro-7 class. I am pleased to see 4 people starting the Novice program in Pro-7 cars this year. If anyone wants to race in the Pro-7 class, they will be more than welcome.
 
My two cents: It's just my first year racing with the senior drivers so my opinion here is certainly less informed than Steve and the other experienced Pro-7 drivers.

First, it sounds like we will not have a choice with the RA-1's next year and the new tires sound like the way to go. I would just like to see any rule change include a grandfather clause for continued use of the rest of our RA-1's (I have a set of rains with the stickers still on them!) As far as wheels go, I don't mind if people want to upgrade to lighter ones. Personally, I'll probably continue to run stock.

Second, if relocating the battery really makes that much of a difference in handling/balance then that also makes sense. Again I'll probably stick with my stock battery until it dies, so I would like to see battery type/size as an option and not a spec'd unit.

Finally, as far as the weight reductions are concerned, again I will defer to the senior drivers in the class. Personally, from what little I know about such things, these sound more like changes one would undertake to move into an improved production or touring class.

I think Jeff may have a good point here as multiple or costly changes (not that I find any of these changes prohibitively expensive) could prevent potential Pro-7's from buying existing cars.

A big thank you to Steve for coming up with these rule changes and publishing them for discussion among the drivers.

Tony Hauser #344
 
I bought the Tipton car.

Don't NASCAR bars automatically include the removal of the window mechanisms/glass?
If so, then all cars should be able to run without.
If not, then this is a safety related change as I don't want glass shattering anywhere near me, with or without a NASCAR bar.

I'll be out there as soon as soon as my license arrives in the mail and my camber situation improves. Positive camber is not good for RA-1s.
I wanted to run Mission, but I just started on getting a Passport Card (4 wks) because the Washington Driver's License people don't even know Federal law and the Enhanced WDL isn't going to happen for me. Jeeeez.
 
It looks to me like rules 1401 - 1404 should be eliminated from the Pro-7 class in Appendix Q (item 12) of the 2008 Competition Regs. These rules give the allowable modifications for Conference Production cars and are more expansive than those for Pro-7 cars set forth in rule 1315.
 
There will be a meeting for Pro-7 drivers and/or owners at my pit (red #70 Pro-7) 15 minutes after the last novice race at Pacific Raceways on 2 August. The purpose of the meeting is to decide what if any rule change proposals we should make for next year. Anyone who will not make it can give their input via email to sroman70@hotmail.com.
 
Guess I should have looked at the schedule for the 2 Aug race at PR. The last race of the day is a Pro-3/Miata race so I guess we should meet about 15 min after it is over. Our meeting shouldn't take long.
 
Can't make this weekend's race so I wanted to check in on this. I feel like anything we can do to lighten the cars and lower lap times at reasonable costs is great. I like the ideas proposed by Steve regarding tires/wheels, battery type and location, and allowing the removal/replacement of unused equipment. If we make header, suspension, differential changes that are compatable with ITA, then I would prefer all changes fit ITA. Otherwise, I don't mind running EIP in group 5. We are currently not very competitive in ITA anyway. I don't think any of the less expensive ideas would deter participation in Pro 7. Rather, I think a faster setup would encourage it.
 
Held a meeting last Saturday. Four drivers/owners showed up. As a result of the meeting I will submit rule change proposals to 1) allow use of the R888 compound as well as the RA-1 compound, 2) remove side windows and window operating mechanisms, 3) allow adapters for use of disk brakes on a drum break rear axle housing and large bearing front rotor on a small bearing spindle. I also wrote a proposal to allow modification of the sheet metal between the A and B pillars to move the upper roll cage bar further from the drivers head. I think all of the new drivers coming into Pro-7 (2 more last weekend at PR) need to run the cars some, think about why they got into the class and then we can all decide how to change the rules a year from now.
 
What about removing the headlights and related motors? I would also like to consider reducing weight to 2200 pounds and allowing a header with a weight of 2400 or 2500 pounds. This would allow those who can to lose weight with all of it's benefits and those who can't to get close on the power/weight scale. Somebody who knows could figure out the appropriate penalty for a header.
 
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