Got a question for you guys. What are the rules for a roll cage on a convertible? I need to know what I have to do to make my car certify to at least an 8.90 in the quarter. I have a 6 point right now with the addition of kidney bars and x bars in the back. I am fixing to add the main halo and front down bars. Is there anything else that I have to add to the cage. My local track let me run last time but told me if I keep running faster than a 6.40 that I need the halo and down bars. It is useless asking our tech guy as he cannot see past his budweiser. I promised them I would have the rest of my cage in next time, and next time I am planning on running 5's after I fix this nasty nitrous surge. Any info would be appreciated. Blair Phillis
Hey Blair, so there's another Buick nut racing a convertible, I'd never do it again, but for now I'm going to push my '65 as far as it will go! Adding the halo bars off the main hoop, basically turning the 6 pt. "bar" into an 8 pt. cage, is a must, all must be welded to the frame, cage will have to be certified after 9.99, this is good until 7.50 (NHRA), I had a friend who' '65 Chevelle convert cage did not pass, his 1 3/4 in tubing which was 1/8 in wall, turned out to be about .002 to thin,(under the minimum) pretty sure there's a 10% margin +or - when sonic checking the cage for cert., he had to redo the cage. So hopefully your tubing is OK.That and an SFI window net, plus all the other "rules" prior to the 9.99, NHRA rules state you'll need a competition license, which requires a physical, a parachute, even if you run under 150mph, and multi layer fire suite with neck pad/brace. How are you keeping the top from "ballooning"?? If ya have any more questions, maybe I can help. Gary G.
Blair, what is your combination? What nitrous unit? How much juice are ya squeezing??? And the car, how much does it weigh?? Gary G
Allright, thats what I needed to know. I have moly tubing that is .083 thick. It is legal. You guys got it tough, a chassis certify guy comes here to our track every year, and mainly just looks for good welds. My top is pretty ragged, but it does not balloon. I actually like the convertible beucase I can drive it to the track, run some times, drop the top then drive it home. Plus its under estimated since it is a convertible adn a Buick to top that !!! I have been having a blast with this car and in fact, there are some people around my area who owe me some money, becuase they did not think it would break the 7 second barrier on the motor. Well Ha, time to pay up !!! Combo is 455 with STG 2TE heads, flat tappet solid cam, 12.5 CR. Motor runs off gas, I have an NX alcohol Gemini twin plate system. I am getting ready to add some alcohol nozzles to this setup real soon. my best et of 6.30 at 106 was on 100 shot. Any more shot than that and the surge just gets worse. Has run 6.51 at 109 on the motor. All on foot brake. I feel it has a lot left as I have a tight converter and can only stall it to 2100 rpm. I have lots changes that are being made at this time. Those include, EM computer, trans brake, 9375 carb, full slicks, and front runners. I don't know the weight but I figure its fairly light. What is the fastest convertible Buick you know of. Just curious. Blair Phillis
Fastest Buick Convertible....well I'm not sure how many of "us" are out there. But...ME..... for now! Or not....my new combo. on motor, with bad 60fts. has gone 6.7 @ 106mph, and with a 100 shot 6.3@ 111mph, I haven't done much tuning, going to play with jetting, and more suspension preload on the rt rear, I know I can get more out of the motor, and then step up to the 200 or 300 "shot", I know it will be fun. I run 1/4, car pulls harder after the 1/8 mile. Good luck with your car, keep me up-dated, we could be the only ones....... Gary Giessen
Blair do you have any pictures of your roll bar just wanted to see where you put the back bars thanks Vinnie. im putting together 1970 buick rag top.
Willie's 71 GS convert runs high 10s in a quarter. See the pics of it in action on page 7 here: http://www.v8buick.com/showthread.php?t=52096&page=7&highlight=willie+convertible
Wichita Raceway Park is NHRA isn't it? You need to get you a current NHRA book and follow it for the convertible. We have never been to that track, but travel around everywhere else out here. Maybe we could meet up in Abilene sometime and run there. What rear gear are you running.
My '65, best motor pass last May, 10.29 @131 mph, has gone 9.31@ 146mph. Shooting for high 8's this year, I have one time slip, 8.86 but terminally "hurt" the motor on that pass.....Car is legal to run 8.50. Gary G.
Gary, what gear are you running? We have to make a gear change to run 1/4 mile now, and trying to figure out where to go.
I run a 3.70 gear, Ford 9" w/ spool.35 spline axles. 29.5 x 10.5 slicks. Don't need alot of gear because of the nitrous. Gary G.
Thanks Gary. Wasn't trying to take over your thread Blair, but ...... We are running 4:10 gear now, with 29.5 x 10.5, and is too much gear for the 1/4 mile. We are thinking 3.42 since Tyler shifts at 6k. That should put is at upper 9's at 140 or so. Problem is, most tracks are 1/8th mile here, and only a few are quarter mile. Regional events are run 1/4. We don't want to change out gears every time, so we will gear for 1/4 and run 1/8th like that.
See photos. If you are wondering it is moly. I am about to cut the back out because the car is getting back halfed this fall. Blair Phillis
What is the fastest convertible Buick you know of. Just curious. Blair Phillis Id say its badbuik! ... 9.31 is flying! Too cool!
At what ET do you need a cage in a vert? Mine has not seen any track time, but I want to get it to one fairly soon.
