powerslide91 Posted December 22, 2004 Share Posted December 22, 2004 I need some clarification on the subframe rules, specific to the front end. My car is a ’71 Pontiac Firebird. The setup is basically the car from the firewall back is a unibody. From the firewall forward it is a bolted on subframe. Attached to this subframe via bolts only (no welds) are the fenders, radiator core support, and the front suspension. The subframe attaches to the unibody through 4 bolts. Now, my understanding of the rules as they would apply for say a 3rd or 4th gen F-body is to allow for K member replacement with available bolt ons. I want to know can I replace the front subframe on my car with a similar bolt on part. Reason for wanting to do it would be to improve the front suspension geometry. The car uses a double wishbone front suspension, and I guess that is where I am getting confused, the rule book talks in terms of leaving the front strut towers alone, but my car does not have strut towers. Here is a link to a picture of one of the aftermarket units I would consider; http://www.rcubedmotorsports.no-ip.com/ ... ivered.jpg Again, as I understand the intent, it is to allow for aftermarket K members, and that is what I’m trying to do, it’s just in my case, the “k member” is a bit more extensive then was probably envisioned. Who can I talk to about getting this clarified in the rule book. I do not want to invest a large sum of money to start building this car up, only to then get thrown out later because someone else later on interprets the rules differently. Thanks! Jeff Quote Link to comment Share on other sites More sharing options...
swhiteh3 Posted December 22, 2004 Share Posted December 22, 2004 You've come to the right place Jeff... I'm sure you'll get answer soon. Quote Link to comment Share on other sites More sharing options...
JWL Posted December 30, 2004 Share Posted December 30, 2004 Jeff- Does the stuff in the picture bolt to the factory framerails or is this a separate deal that runs from the firewall forward? Excuse my ignorance, but I haven't spent a great deal of time poking around under the earlier model cars. -JWL Quote Link to comment Share on other sites More sharing options...
nasaracer32 Posted December 30, 2004 Share Posted December 30, 2004 JWL - I do think that piece bolts right on the the front of the car. I have been helping a friend work on a 68 Camaro and while I was under the car, I noticed that the front clip would unbolt from the car. We had to take out one of the bolts in the rear of the 'sub frames' (in the front of his picture) to get the tranny mount out. Quote Link to comment Share on other sites More sharing options...
Guest Posted December 31, 2004 Share Posted December 31, 2004 JWL - I do think that piece bolts right on the the front of the car. I have been helping a friend work on a 68 Camaro and while I was under the car, I noticed that the front clip would unbolt from the car. We had to take out one of the bolts in the rear of the 'sub frames' (in the front of his picture) to get the tranny mount out. To get right down to it, replacing the front subframe (FRAMERAILS) you are modifying the framerails. Our car got hammered because of two tiny notches and now NASA is actually considering letting someone replace the entire framerail? Seriously guys, this seems pretty cut and dry. No framerail modifications per the rules and replacing the entire rail seems to be a rather obvious modification! Thoughts? Quote Link to comment Share on other sites More sharing options...
powerslide91 Posted December 31, 2004 Author Share Posted December 31, 2004 JWL - yes, the entire part pictured in my link bolts to the car. There are 4 main bolts, 2 that attach to tabs on the firewall (in the pic it attaches to the two tabs pointing left / right in the middle of the pic), and 2 that are under the car (at the bottom of the pic), more or less under the front seats. There are then 2 more main bolts that hold the radiator core support to the front subframe. B-tone - this is why I'm asking for clarification. I'm not as sure if it is cut and dry. Another way of thinking: the frame rails are welded to the unibody of my car in the same sense that the more modern cars are, except for this car, that is only from the firewall back. But the part I pictured is a subframe, performing the same function as a K member on a modern car, only additions are that it also locates the top control arm and the top shock mount (not strut). Again, I want to understand intent in the rules. As near as I can tell, within the rules, I could modify the stock front subframe to relocate the mounting points (both top and bottom in this case), convert to coilover, and switch to tubular control arms. But the reality is I lack the time or experience to do all this engineering. By swapping out the subframe, I am using a pre-made, bolt on part to improve performance. Which I thought was a key tenant of AI, a open rule system that encourages bolt on modifications. I basically have the car, and think AI would be a fun place to play. But I am not willing to invest the money to build up the car only to be hamstrung by 1960's suspension geometry. Hence the desire for the clarification. Thanks for the replys. Other thoughts? Jeff Quote Link to comment Share on other sites More sharing options...
powerslide91 Posted December 31, 2004 Author Share Posted December 31, 2004 I'd like to add for anyone that is on the rules committee, I would be willing to provide any technical data or more detailed pictures of the car and it's construction to help clarify what is involved. Please just email me or I could post here in this thread. Thanks, Jeff Quote Link to comment Share on other sites More sharing options...
racercosmo Posted December 31, 2004 Share Posted December 31, 2004 I say let it run. Quote Link to comment Share on other sites More sharing options...
JWL Posted January 4, 2005 Share Posted January 4, 2005 Jeff- We talked this over and have decided that the long bolt-on rails are indeed "framerails" per our definition and can't be other than the original design. You can bolt whatever you'd like to those rails, but you can't add new rails that don't conform to the original specs. Thanks for the information and sorry we couldn't make it happen for you. -JWL Quote Link to comment Share on other sites More sharing options...
PAI Racing Posted January 4, 2005 Share Posted January 4, 2005 Booooo! Quote Link to comment Share on other sites More sharing options...
trackboss Posted January 4, 2005 Share Posted January 4, 2005 Another option would be to modify the front in the same way PAI racing has (it's the red camaro right?). It seemed to have a really nice custom front suspension. Who did the work anyway? Quote Link to comment Share on other sites More sharing options...
PAI Racing Posted January 4, 2005 Share Posted January 4, 2005 Pablo Mobius did a lot of the work and certain things were done by Maeco Motorsports. Maeco does a lot of vintage Trans-Am and BP cars and modern recreations of vintage TA cars (like mine). Pablo did the vast majority of the work on the car and continues to support it. Thanks for the compliments. The car took a ton of time and cash to finish, but I dig the finished product. I initially planned to run a bolt in front Subframe with C4 Corvette parts (the Wayne Due subframe) but changed my mind and decided to keep the car more vintage legal in the event that I decided to take it vintage racing instead. Quote Link to comment Share on other sites More sharing options...
powerslide91 Posted January 7, 2005 Author Share Posted January 7, 2005 Boy, my ISP picked a bad time to stop working for a few days... JWL and all on the rules group - thanks for discussing it. Of course, I am bummed by the decision but understand. I will need to ask a few more questions then since I believe the stock subframe still falls into a bit of a gray area. I will need to post the questions next week since I am trying to get ready for a race this weekend. PAI Racing - can you send me some contact info for shops you mention? I would like to talk to someone familiar with this setup and how it would apply to AI racing. Also, if you have any info on your specific car that you are willing to share, let me know! My email is powerslide91(at)yahoo(dot)com. Thanks, Jeff "Second gens unite!" Quote Link to comment Share on other sites More sharing options...
PAI Racing Posted January 7, 2005 Share Posted January 7, 2005 Jeff, You have a pm. Sean Quote Link to comment Share on other sites More sharing options...
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