Launches....
 

On a first gen, What rpm launch has given you the best results?

(drag race)

It really depends on a lot of things. Clutch, tires, road conditions, mods you have performed. The only way to know is to practice. When it is hot out and the road is a pretty good, non- slick road i launch from about 5000rpm with good results. My only mod so far is a racingbeat header. Iv'e got plans for many more mods soon. :D When the road is slick or my motor is feeling especially torquey for one reason or another I launch at about 4000rpm.

Re: Launches....
 

10,000 RPM

Just Kidding. Depends on Many factors.

1) Engine HP/Torque Curve (12A? 13B? Turbo?)
2) Flywheel (light/heavy)
3) Tires - (Grip/Slip)
4) Clutch (Grip/Slip)
5) Street Conditions (Smooth, Rough)
6) Suspension (Stock/Modified)

Plus there are many more little details I am sure thsat I am overlooking.

For your car, go to a large open area and try it out.
Play with it so you take off fast without Bogging down.

On mine, If I let go of the clutch too fast, I get wheelspin, no matter what RPM.

Since my car is presently stock (for now),
I "ride" the clutch out from about 4K RPMs so I
can take off Extremely quick with NO wheelspin.
On an SE, the also has the benefit of the 6 ports being in a significantly "open" position.

The bad part is, this wears he clutch faster.

I've beat many faster cars than mine because of my launch alone. I will usually pull 2+ cars with this alone.

If I had Heavy Duty Parts, and Grippy Tires, I would just pop the clutch at a higher RPM and go for broke.

My $02 Cents

i'm not going to win any drag races with my clutch the
way it is right now(fried)but to day my new center force
clutch is going in,,then it's 4500-5000 rpm's not to high
to spin the wheels, but to hook-up and LAUNCH

5000-5500 with a stock, somewhat slipping clutch, open diff, and heated economy tires. Any higher and it spins the tires instead of the clutch, any lower and the engine bogs too much. Best 60' times are in the 2.1 range which also includes falling on its face after the clutch grabs :)

Now that I have a car with an LSD, I can try launching at like 6000-7000 or so. That way the clutch will still slip instead of the tires, and when the clutch grabs the engine won't be out of its powerband. (I also am not running the ported engine anymore, sadly)

Here's to burning rubber and breaking transmissions :1party:

Launching would be lots easier with more torque and/or lower gears... more torque means breaking trannies so you have to put a T2 trans in... deeper gears means you make the driveshaft spin faster for a given speed and you constantly wear out tranny output bushings... Oh Well! I'm thinking of giving in and going with a big ol' hairdrier strapped to a 12A in a couple years...

hmmmm.
if i launch mine above 2k, i do a burn out entirly through first gear. now i usually launch at around 1500-1700rpm

Geez what do you have under the hood? (Or do you just have bad tires?)

I forgot to mention that... I use Goodyear Club tires, which have nice pliable sidewalls and that wonderful Goodyear rubber that sticks harder when you heat 'em up. 20-22psi and a good-sized burnout in 2nd gear.

http://www.geocities.com/izzmus/burnout.html
http://www.geocities.com/izzmus/about.html

Click on picture for larger version:

http://www.ajc13b.com/rx7-40(sm).jpg

26x8x15 American racer slicks.
Decent burnout
7000rpm
Step off clutch.
19psi and C16
Results=1.6 60ft and 11.1 @ 125mph

225/45/17 Yokohama A032R street tyres
Big 2nd gear burnout
4500rpm
Release clutch at steady rate
17psi and pump fuel
Results=1.7 60ft and 11.8 @ 118mph

What rearend are you running?

Borg warner
31 spline billet axles
4.10 LSD
3.5 inch tailshaft

Here is a pic of my old car lunching,
26x8 american racers,
8000 rpm step off clutch
1.51 60'
10.94@125

Im with you on that, when my dad drives our -SE anything over 2K and were burning rubber :). The other day we wasted one of those funny looking V6 Eclipses from one stop light to the next down in Redmond on Avondale road, it was great, smoking tires and everything :D. Also same drive home we made a Subaru Legacy fel slightly inferior to us :D.

~T.J.

peejay, i am runing on the stock bicycle tires.

AJC13B & 10sec rx7:
What kind of suspensions are you running? i've seen back halved cars that didn't launch that straight!

mazdaracing.com claims their car's suspension is all origional and it appears to launch pretty straight.
http://www.mazdaracing.com/dsc_2225.jpg

anyways, back to the question:
all stock, LSD and 205's. dumping the clutch at 5-5.5k seemed to work pretty well.
i'm still working on the launch w/ the mods. dumping from 5k, it goes straight to the redline and spins way too much. dumping at 3.5k seems to work ok. it doesn't spin too hard and the tires stop spinning around 5k. right in the power band. it feels like launching at 5k and riding the clutch for a second works best. i will not find out for sure until summer. :)

massive spin at 2k? it sounds like someone needs to ditch the dry rotted cookie cutters.

brake - I have loweed king springs and koni shocks. The springs are far to hard and I get alot of 'bounce' out of the hole.

When I go back and run my 10 I will have standard springs in the back so I get more squat and more weight over the back end.

Yeah, ditch the hockey pucks! I'm tellin' ya, if you're going to run stock-size tire, get some Goodyear Clubs. They're cheap and they WORK especially with a good burnout!

I think mine were $34 apiece and they lasted me about 25,000mi, which is higher than average :) Gonna have to get me another set before the race season starts!

it is not that i am running those machbox tires by choice. money is a bit tight right now, and my suspension is shot so i have to replace that first... but soon i will get some real rubber (and bigger rims) and be able to launch properly.

I'm going to see if they make Clubs in 185/80-13s... should be a bit more traction than 185/70s, and certainly a lot more than low-profile tires will have.

This year is gonna be FUN! :D

I am running Monore GT Gas shocks, with lowered heavy duty springs, not sure on the brand,
The only prob i have had is bending the lower trailing arms which were fixed by fitting larger steam pipe units, and ripping the top arms apart!
My car also has a 9" diff.

I guess it would depend on what tires you have. I've seen a guy with an '83 with street micke thompsons launching like at 7,000-7,500 rpm's and get a real good launch, but I gues that it depends how good your traction is

7k seems a bit high for a launch.. i am sure that you can do it with good traction, but why? if you are lucky that puts you into the top of your powerband, but for most that is above it. off the top of my head i would say go with 5k as long as you have good traction. that way you can still pull a little bit of power in first gear and not have to worry about shifting right after you launch. i would think that that would be easier on your clutch too.. ofcourse, i am sure that someone will correct me if i am mistaken

When I'd launch at 5k it would bog when the clutch would grab... it would pull the RPM down to about 3k or so and the car would fall on its face.

one simple way to solve that problem.. more power

what are the widest tires taht can be fit with the stock suspension?

riffraff - You can make as much power as you like, but if you bog off the line, no amount of power will make those few tenths back. The only way to have 'lighter' launches is to shift your powerband. Then you effect top end performance. I know what I would prefer...

jeremy - 8.5 inch wide slick is about as wide as you can go with minor gaurd mods...