Landracing Forum

East Coast Timing Association => ECTA Rules Questions => Topic started by: jjolly on May 15, 2016, 07:08:32 PM

Title: Skirts
Post by: jjolly on May 15, 2016, 07:08:32 PM
My C/CGC Mustang has now gone 187 with a C4 auto trans and a 2.73 diff. The auto trans is a bit of a downer and I will certainly get a 4 speed in it as soon as my wife will let me (only partly joking) for a run at 200..next best thing to a 4 speed (or nitrous) is aero. I am redoing the air dam for June, can I run skirts? I dont want to race IN a skirt, but install some on the car. I have a set of moons here that just might make it on too.. Trans, moon and skirt all in one post. I feel there is a joke in there somewhere...
Title: Re: Skirts
Post by: jacksoni on May 15, 2016, 08:12:28 PM
GC class rules say no streamlining as described in para 4.CC unless specified (as allowed- my addition). Skirts are not mentioned as allowed and therefore would not be legal. (IMHO). Unfortunately, there is not a /CC (/CCC) category for classic as skirts are allowed there. If your goal is 200, you can certainly run time only and put skirts, belly pan etc or other changes that would be ok for /CC. Lobby Keith and Brian to add a classic /CCC category (SCTA doesn't have one either and ECTA mostly follows SCTA rules). Is your car otherwise legal to run /SS or /RS? You could run /CALT and cover grille and lights etc (but Charles Venable holds that record at 203+) but would let you run legally and make a change that may well be better speedwise .
Title: Re: Skirts
Post by: jjolly on May 15, 2016, 09:15:28 PM
jacksoni, thanks for the reply. The gearing in the car is not going to get me to 200 in the mile, a 190 pass in June would kick ass though! The car was at 7100 with the 2.73 gear at 187 mph. The 3.08 would have the motor up about 9000 RPM. Thats a little higher than I want to run.
 I know I can tape it up and I may, in time only. I am going to stick it out in my class. I don't want records in other classes that may be soft, my belief is it may discourage someone from coming out and trying this type of racing if his car can't get close. My car is near real street, I could have it legal by June but I think I'll save that for next spring. I'll get the manual trans after the June race. I have considered nitrous. An extra 100 horses couldn't hurt on a time run..
Title: Re: Skirts
Post by: Captthundarr on May 15, 2016, 09:42:29 PM
what about ride height, can you lower da beast??
Title: Re: Skirts
Post by: jjolly on May 15, 2016, 09:49:17 PM
It is slammed. K member and headers are about 1.5-2 inches off the pavement.  Maybe a 25.5 inch rear tire instead of the 26? Will save my money and buy a close ratio trans..
Title: Re: Skirts
Post by: kiwi belly tank on May 16, 2016, 12:09:15 AM
With a shorter tire you'll need a bigger gear, you need to loose the C4 with no lock up converter.
  Sid.
Title: Re: Skirts
Post by: Jack Gifford on May 16, 2016, 01:14:59 AM
Or use a "tighter" converter. I once ran a "tight" Fairbanks converter on a C4 behind  a 289 in a street Falcon Ranchero. My goal was fuel economy, and it did help.
Title: Re: Skirts
Post by: jjolly on May 16, 2016, 05:47:43 AM
The C4 is the problem. I did have a converter built for this. It is slipping approximately 600 rpm at speed in high gear. The drop off between first (2.46) and 2nd (1.46) is just a little too much. Then of course are the planetary gears spinning at a gazillion rpm. 190 with the C4 is the goal. I just may have a close ratio toploader available from a guy locally here. That will be my project after the June race.
Title: Re: Skirts
Post by: kiwi belly tank on May 16, 2016, 09:35:08 AM
If it's a race car only, you could always do a direct drive coupler like a lot of Bonneville guys do & just push it off the line & pull it into gear.
  Sid.
http://www.jegs.com/p/TCI/TCI-Circlematic-Front-Pump-Drive-Kits/748508/10002/-1
Title: Re: Skirts
Post by: noboD on May 16, 2016, 09:41:12 AM
I am not familiar with the class. But if skirts are not allowed what is done with cars that came from the factory with skirts, like Thunderbirds?
Title: Re: Skirts
Post by: jacksoni on May 16, 2016, 11:11:28 AM
I am not familiar with the class. But if skirts are not allowed what is done with cars that came from the factory with skirts, like Thunderbirds?

I think here you are talking about fender skirts, not under body skirts which is what rule 4.CC.7 is referring to. However, generically, rule 4.CC says any device that controls or limits airflow in or around the car and is not part of the original body (emphasis mine) is considered streamlining. A fender skirt is not part of the "body". I can't find a specific reference to fender skirts but have the sense from the past that they are not allowed. May be wrong there. Looking at photos of many cars in many classes I do not see ANY that appear added. If it was helpful (and should be) and was legal I'd expect to see some. An exception was a Honda Insight which did have in the photo I saw. Don't know if ran that way. Moon discs are legal. I have seen reference to wind tunnel data suggesting they are of minimal help. Look nice though. :) However, watch wheel offset so as with modern street cars the wheel/tire is not outside the body. A factory skirt as on a T-bird, may pass some places but not sure legal SCTA/ECTA as a bottom line. I suspect if you show up with them, no one will say boo but then again, been wrong before (well, once or twice--:)  )
Title: Re: Skirts
Post by: jjolly on May 16, 2016, 03:59:48 PM
I was talking body skirts. Thought about running them the length of the seam under the rocker panel.  May still make them up and try them out in June and see if they make any difference. I am bringing plenty of tape too. Time only runs or a class change may be in order.
Title: Re: Skirts
Post by: Dynoroom on May 16, 2016, 05:11:54 PM
The SCTA allows factory skirts as delivered in Gas Coupe. You cannot mix years or vehicle types.

Below see legal & Illegal...
Title: Re: Skirts
Post by: jjolly on May 17, 2016, 05:44:15 AM
Thanks Dyno. I am going to improve the air dam and lower rear a couple inches, spin the motor a little higher in 1st and 2nd and hope for the best! 
Title: Re: Skirts
Post by: Cajun Kid on August 23, 2016, 10:45:25 PM
jacksoni, thanks for the reply. The gearing in the car is not going to get me to 200 in the mile, a 190 pass in June would kick Acura though! The car was at 7100 with the 2.73 gear at 187 mph. The 3.08 would have the motor up about 9000 RPM. Thats a little higher than I want to run.
 I know I can tape it up and I may, in time only. I am going to stick it out in my class. I don't want records in other classes that may be soft, my belief is it may discourage someone from coming out and trying this type of racing if his car can't get close. My car is near real street, I could have it legal by June but I think I'll save that for next spring. I'll get the manual trans after the June race. I have considered nitrous. An extra 100 horses couldn't hurt on a time run..

Not sure a 203.xxx is "a soft record"  in C/CGALT
Title: Re: Skirts
Post by: Stan Back on August 24, 2016, 12:07:40 PM
There's a pretty big HP increase needed between 187 and 203+ (someone here will tell us).  Probably can't find the answers with gears, either.
Title: Re: Skirts
Post by: jacksoni on August 24, 2016, 01:49:43 PM
Happy to oblige- about 25% more than he has now. :cheers:
Title: Re: Skirts
Post by: greenjunk on August 27, 2016, 12:49:27 AM
Thanks Dyno. I am going to improve the air dam and lower rear a couple inches, spin the motor a little higher in 1st and 2nd and hope for the best! 

Be careful lowering the back of the car and not the front, you're going to take air off the rear spoiler and the nose of the car will go up.