RX7 speed racer

I have a 91 n/a. What can I do to get the most horsepower out of it.
I talking quit jobs. Without buying mods. Any suggestions?

jeff_oner

take out the stock airbox and either use a cone filter if you have one, or in a pinch you can use pantyhose to filter the intake hose. also play with the timing. also for dragging, double clutching doesnt hurt either.

RX7 speed racer

Could you explain the timing thing a little bit more in detail?

quick 7

How does double clutching help when you're drag racing, or accelerating?

Scott 89t2

havn't you watched F&F?? come on man everyone's doing it! LOL

jeff_oner

i cant rember for sure, but i think if you advance the timing a little it will give you a little more power, but try different settings and see how you like it, people have different preferences.

as for the double clutching, i cant say from personal experience, since im not that into dragging, but i have a friend that does it often and he explained it to me, it kind of gives you a little boost when shifting because it gets the rpms up (its kind of like revving up your engine then droppeng the clutch to burn the tires)

and one more thing, learn how to launch your car, it will make a difference, you lose a lot of power when the tires burn off the line.

hope i helped a little

RestoTII

to my understanding, which is going to be flamed.... double clutching will help the clutch set into the gear. Basically, teeth are trying to go togheter, and without a synchro mesh, it grinds alot, but with it, they should slip into each other smoother. By double clutching, you seperate the "out of gear" and "into gear" movements, making it smoother. I've seen that double clutching only helps when upshifting, only helps when downshifting, and doesn't help at all.... so I'm just gonna keep single shifting my TII until I hear more evidence, since I don't really have time to investigate things like that.

BhamBill

No flaming, but double clutching is ONLY for downshifting. Last I heard the idea in drag racing is the quickest shift possible. I used to shift the Muncie in my 56 Chevy without the clutch. Double clutching makes the shift take twice as long.

Nick110

well i really don't understand how doubleclutching can help you accelerate any faster. i never understood that concept and didn't even know that it existed until F&F. all i know is doubleclutching helps with downshifting though and while going through the twisties as it allows you to downshift smoothly.

Blue Goose

What your friend id doing is called feathering the clutch; basically letting it slip to try to help your motor get to it's powerband quicker. It'll wreck your clutch in a hurry by glazing it over if you do it too much, or too often. Double clutching is done primarily by semi drivers and racers with no synchros in their gearboxes to help bring the engine and trans closer in speed so it will pop in gear. If you need a couple extra HP real quick, try taking off all accesory belts (alternator, A/C, PS) but NOT the water pump belt. Just don't forget to put them back on or you will have a very dead car (well, alternator anyways). You could also try gutting as much of the interior as possible, which is actually pretty quick, and includes passenger seat, carpet, spare, jack, etc, etc...good luck!

EDIT: Bhambill, you had a '56 chev? If it was a shoebox, you just made me a jealous bastard!

Roy James

This is exactly right, it helps transys with out synchros to match up the speed of the gear to the speed of the motor, its basically acting like a synchro. In that case, if your trans has syncrhos, whats the point in taking longer to shift gears? To shift faster in drag racing "power shift" it, in other words, dont take your foot off the gas when changing gears, just be hella quick so you dont blow your engine, haha. i hoped i helped, and correct me if im wrong.

SpeedRacer

You do not generally double-clutch to downshift. That is what heel-toeing is for. Double clutching is to keep the turbo spooled up while upshifting, and save on syncros. It is not for shifting faster, because obviously it isn't faster, but if it will keep your turbo spooled up, and save your syncros so your tranny will last longer, than it is worth it. Heel-toeing is used also for saving syncros in your tranny by matching rev's. It also allows you to downshift earlier so you can accerlate out of corners faster. Its is REQUIRED to auto-x well especially in RX-7s with bad low-end. Coming into a corner and exiting at 30mph will suck in second gear. I can heel-toe into 1st gear going 40mph if I want to and never grind the gears. I don't recommend it, but it can be done quite easily actually.

BuddyRX7

Take the AC and Power Steering belts off (if you have em) that should get you a few more rotary gerbils

nima_taba

Say guys, someone mind explaining what all this heel-toeing and double clutching is? I've heard the terms lots but I never know what they are and how you do them.

Thanks,
Nima

jeff_oner

as i said before, i dont know much about doubleclutching except what my dragger friends tell me.
on the other hand i do have a pretty good idea what heel-toe is. it is when you use your toe on the brake and your heel on the gas, to control drift and other hard cornering.

Re-Speed.com

iTrader: (3)

Much easier to use your heel on the brake and roll your foot onto the gas. Try it, while reading this. You see, your ankle is used to control the throttle as it roll an arc. The other way puts your heel onto the gas and you ankle folded back to far and your leg twisted to much to be effective and smooth. Double clutching is normally used to down shift. It helps with the syncros. You can upshift and downshift with out the use of the clutch. Some cars are easier to do than others. Try down shifting first to get the feel. Use the above mentioned heel and toe method to slow down for a red light. use your heel to slow the car down, at the same time pull it out of fourth into neutral. use your toes to increase the amount of throttle while trying to push into 3rd. Once the rpm of the engine matches your speed the shifter will just fall into place without the use of the clutch. Same theory for faster corners just differing rpms. As for keeping the turbo spooled up - You do not need to double clutch for that. The idea is to have enough throttle control with your foot and knowledge (Seat Time) with the car to push in the clutch and let out of the gas just enough to keep the same rpm. Which is a must to learn for performance driving of any kind.

SaabGuy

People often confuse double clutching with "feathering". When I raced my quad I know all about those terms.

Double clutching is used if you have no synchros or if your tranny plain sucks. I actually do it when my tranny is cold cause it makes it shift smoother.

Feathering is just reaplying the clutch several times to keep the rpms up. its hard to do especially if you have a high powered car, cause the rpms will shoot up very quick. it was easy to do it on my 250cc quad cause it was only like 35hp. Feathering will severly whoop a clutch, especially a stock clutch. I hear its great for those stiff ******* though.