Thread: Tech question for tech re fed

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Originally Posted by canadianal

Were looking at the book and read the brakes general regs 3:1
what is ment by "if hand brake used it must be connected to foot brake.
are you supposed to have both?
am looking at a FED car which has a hand brake but no foot brake.

Back in the day, when dragsters first appeared on the scene, there were no good automatic transmissions, so you usually used a 3-speed standard (four, five and 6-speeds were far off in the future). You'd launch in second gear and shift to high downtrack. If you had enough hp, you'd run high only or just run direct from clutch to diff. With the skinny little cockpit, there was no room for 3 pedals, so you used a push or pull handbrake. Even if there had been room for 3 pedals, you'd have needed 3 legs to stage the car.

It has been a long time since I've seen a manual shift FED. Every one I've seen in the past few decades has used a 'glide, replacing the clutch pedal with a brake pedal and eliminating the handbrake. No more missed shifts and way more consistent. If the car has a manual, I think most any tech guy in your area will let the car run with only a handbrake if that's the way you want to do it. I'd let you make passes if everything else was up to snuff. It can get pretty dicey in those cars though, if you're having a problem and need two hands on the wheel to control it and also need brakes at the same time.

I have heard lately of sportsman dragsters using front brakes activated by a handbrake and operating the rear brakes conventionally with the footbrake. When you apply the rear brakes in the eyes, sometimes the car will begin to bounce on the rear tires and the brakes will be ineffective, with nothing to slow you down but the chute (hope you packed it correctly). With a tap on the front brakes via the handbrake, the car will immediately settle down and you'll have rear brakes again.

If I had a FED, I think I'd seriously consider the front brake option. The whole thing couldn't weigh more than about 20 lbs and with each 100 lbs slowing the car by 1/10th of a second, the increase in ET would be negligible. In today's bracket racing, you're running on a dial anyway, so it wouldn't matter much.

With an automatic, at 10.99 or 135 mph, you'll need a SFI 4.1 transmission shield or aftermarket tranny case that's certified as 4.1 from an aftermarket supplier. At 9.99, you'll need an SFI 29.1 aftermarket flexplate and SFI 30.1 flexplate shield. For the tranny shield, you have the option of a blanket which would fit better in a FED but will sometimes hang up the shift linkage if not installed properly and definitely hold heat in the tranny more than another rigid type of shield. The replacement time on a flexible blanket is 2 years, where a rigid shield is 5 years. Problem with the rigid aluminum or steel shields is that they don't fit tightly around the tranny and afford (in my opinion) less protection to the driver, particularly in a FED. Neither of these will address the problem of the flexplate shield. Again, the rigid flexplate shield takes up a lot of room, room you don't have in a FED. An aftermarket trans case will give you the most room, but is about $1,000 and still has a life of only 5 years before replacement. The other option is the one I would use. A composite shield that covers both the tranny and the flexplate and fits snugly around the case. You'll have to grind off the locating bosses that GM used to machine the case, but that's no big deal. It costs around $330 and has a 5 year life, so figure a cost of about $66 per year to use it.
CSR Performance 831 - CSR Super Shields - summitracing.com

The SFI 29.1 flexplate has a life of 3 years. Keep the receipt that came with it to show the tech inspector, because if will be next to impossible for him/her to see the tag on the 'plate. To be brutally honest with you, you probably won't be asked for it anywhere except Firebird.

By the way, use your dial caliper to measure the front spoke diameter if it has spoke wheels. Minimum diameter is 0.100" or they're junk. Also check for a chassis certification sticker. If no sticker, the car may not be worth anything except scrap metal. There are 3 SFI specs on FED's, depending on how quick they're gonna run.
Main

If it is certed, check the date and ET limit on the tag. The older tags did not show the ET limit, so you don't have any idea of what the car will cert to until you have a chassis certification inspector look at the car or you purchase the chassis specs from SFI and compare them to the car construction.

If no cert tag and you're still interested in the car, there are two ways to proceed.
1. Contact Jonathan Adams, NHRA Northwest Division Director email jadams@nhra.com or Dave Scheffel email dscheffel@nhra.com to have one of them come look at the car or trailer the car to one of them before you lay down your money.
2. Purchase the appropriate SFI specs for the ET you want to eventually run. Strip the car of all tinwork. Procure a sonic tester to test tubing wall thickness and a dial caliper to check tubing OD. Use a tape measure to measure between junction points. Compare the construction of the car to the SFI specs.

Pay attention to General Regs 2.4......if it were my car and my cajones were right over the pig, I'd be fashioning some 1/4" steel plate, welding pieces together to fabricate a form-fitting shield and prevent personal injury from a grenading diff.