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h22a accord
20-07-2005, 10:00 AM
ive been reading that for goor E.T's that a high rpm launch is needed.

ive tried in my car and i just get wheel spin and hopping. For a decent launch i have to take off at 3000rpm and even then cant use full throttle as i lose traction and get hop.


What would i have to change on the car to eliminate this ?

newmski
20-07-2005, 10:39 AM
ive been reading that for goor E.T's that a high rpm launch is needed.

ive tried in my car and i just get wheel spin and hopping. For a decent launch i have to take off at 3000rpm and even then cant use full throttle as i lose traction and get hop.


What would i have to change on the car to eliminate this ?
1st issue - you have a fwd car and will never be as "good" as a rwd launch
2nd issue - were u using slicks?. street tyres on fwd + high rpm launch will always = spin/hopping

STOCK
20-07-2005, 11:06 AM
I thin kyou have to bite the bullet and learn how to ride the clutch a bit :p

EG5
20-07-2005, 11:27 AM
traction bar , proper suspension set up , drag radial / full slicks , proper lsd , good clutch > its a must.

h22a accord
21-07-2005, 09:53 AM
I thin kyou have to bite the bullet and learn how to ride the clutch a bit :p

thanks for the insight buddy......

DaPlaya
21-07-2005, 12:08 PM
i would take EG5's advise. Looking at his 1/4 mile time he wouldn't be doing much wrong! Damn sub 13sec ppl :P

h22a accord
21-07-2005, 04:00 PM
thanks eg5 :) ive got the power, now i just need to do what you said plus some stripping of the interior and maybe i'll get a low 14.

SmIrNoFF
04-08-2005, 01:34 PM
let abit of the air pressure out of ur tyre......... it may help that tiny little bit

PAPZ
04-08-2005, 02:07 PM
also if you have a coilover setup, set the stiffness on a medium to a high setting and lowest ride height for the front and the stiffest and highest setting on the rear. this might help you get down the track a little quicker.

Non Vtec
04-08-2005, 06:09 PM
I have to disagree have the car as low as possible all round, low centre of gravity, less weight transfer, less aerodynamic drag, faster time.
As for suspension depending on your budget and your car as to whats the best mods, if you have an EG-EK etc chassis get traction bars for the car, the will help alot, also coilovers are a got help, but Get a 750-1000lbs spring for the rear and run around 600lb's in the front. get adjustable shocks, depending on the tyre pressure as to where to have your shocks set.. I'm assuming you'll be on a near full road tyre.
So, you'll have the pressure around 12-16psi probably start at 20psi and drop from there til you start to loose more traction than you have gained. set the rear suspension on hard, and pump the rear tyres up to about 40psi. If you havea big hole in your grill, steal a real estate agents sign or something like that and tape it on over the hole, that will gain you about 0.2 seconds alone. The list goes on..
If you spend some money and go to a Semi slick, or full slick, then Do your warm up skid in 2nd, by this I mean dump the clutch at 5500-7000 in 2nd with the handbrake on to warm the tyres, don't try shifting to 2nd from 1st. On semi's and slicks you'll need to play with tyre pressures even more. Personally I run my slicks at 5.5psi the first run they start at 6psi and end up at 10-12psi after the run so check them again and let the down accordingly. Suspension settings will be different again since slicks will mean no wheel hop. so you can adjust the front harder to stop the lifting from happening...
Anyway good luck...

Civic Type R
04-08-2005, 06:23 PM
Nice information there dude.

Can you just elaborate on this traction bar and where it goes and cost etc ?

cheers :)

h22a accord
04-08-2005, 06:32 PM
Excellent info non_vtec, the mods should sticky that post.

Non Vtec
04-08-2005, 06:36 PM
traction bars are basically a bar that goes between where your factory tow hooks mount to the car and go back to infront of the wheels. they stop the wheels from moving front to back which is what causes the wheel hop.
I beleive Yonas and Z10 had a set for the EGK20A.
But full race, Jimfab, Z10 motorsport http://www.nolimitmotorsport.com/z10/ and a few other firms in the USA make them for a good price..
http://www.nolimitmotorsport.com/2/z10-1001.jpg

I also forot to add about launching at high RPM's is that sometimes you need to forget about trying to get traction, even if the car is spinning you maybe faster time wise to keep shifting and keep the throttle flat to the floor.
I launch at 8000rpm in 1st, have no traction in 1st and shift into 2nd by the end of the 60ft. I run 1.55-1.61 60ft's all day long.. My car spins in 1st but it barely spins in 2nd, you'll get traction easier in 2nd than in 1st.. Its just something else to try, even Yonas took some convincing...

j-specAccord
04-08-2005, 06:45 PM
tyres and pedal work. i launched at 5000rpm and got traction fairly easily with only 1/3 tread left and all that i am using is nankang super streets which retail at like $225 each. i did a 5 second wheel spin to heat them up and rode the clutch very very slightly to get off the line cos launching at 5000 and juz dropping sux for your axles

h22a accord
04-08-2005, 08:00 PM
j-spec what size tyres were they?

SKREMN
04-08-2005, 11:09 PM
Have a look at your bushes they are prolly thorn / ripped and you might be getting excessive wheel hop from these

EG5
05-08-2005, 12:32 AM
i agree with non vtec ( garry )
i get off the line at 8000 rpm , tyre pressure around 10-14 psi on m/t slicks.
what i learnt from the past runs on cars ive raced :
* rolling and spinning is alot better than having full traction *
full traction will makes the car bog and goin slower off the line and produce slower ET

j-specAccord
05-08-2005, 10:02 AM
j-spec what size tyres were they?

225/35 18inch speedy lite 7's
next time i go to the strip im fitting 235's and im hoping to break 14.5 with only the mods i have, nothing more

Civic Type R
08-08-2005, 06:24 PM
ok it appears that my launch methods were incorrect !
great info Garry. I will keep the wheels spinning next time and see how i go :D

But at what rpm should i launch with silica compound street rubber ?

edw-R
09-08-2005, 09:15 PM
OOOOO...i tried to launch at high pm. Jumping all the time. Maybe my coilover is too hard(14k) and my camber is too negative (-3.5).

GSI-PSI
09-08-2005, 09:30 PM
i got a beta 60 footer time wen i ran on 17" street rubber than when i ran on 15" semi slicks. Though my best 60foot on slicks was axle tramping all of first gear compared 2 spinning or rolling off the line.

online
11-08-2005, 06:29 PM
also coilovers are a got help, but Get a 750-1000lbs spring for the rear

You wouldn't run something that heavy with bars on the back though.

ginganggooly
11-08-2005, 08:10 PM
I was trying a few different rpm launches on street tyres, i found 3-4k would just bog and i'd end up with lousy (2.2-2.3) 60' times. 5-6k was the sweet spot for my car, dropped the 60' times down into the low-mid 2.1 bracket. Axle tramp didn't become a problem until i started trying to take off above 6.5k rpm...

Shock settings made a huge difference- when left dialed in to full stiffness on all corners my 60' time went up by about 2/10's over what it was when i had the front on full soft and rear full stiff.

I went out and picked up a set of traction bars recently, it'll be interesting to see if i can get away with 8k rpm dumps then...

Non Vtec
12-08-2005, 10:30 AM
You wouldn't run something that heavy with bars on the back though.

Nah I changed to something alot lighter with the bars on the back... haven't tested them yet... hopefully run some nice mid 10's very very soon

MR-VTEC
12-08-2005, 11:35 AM
what options are there for the h22a in relation to aftermarket lsd's? also what kind of prices would i be looking at supplied and installed?

or am i better off trying to source a factory one from overseas?

online
13-08-2005, 08:08 PM
Nah I changed to something alot lighter with the bars on the back... haven't tested them yet... hopefully run some nice mid 10's very very soon

we are looking for some 10sec pass ourselves :thumbsup:, when you looking at going out again?

Non Vtec
14-08-2005, 03:39 PM
Hopefully in the next couple of weeks. I might have to try and get out before you guys run at the jamboree, I might be able to be the first in australasia if the car can do it..
What are you guys running in the all motor set-up, I'd be interested in finding out some more about it etc.. Since not many people around us are building them, unless you go to the states etc...
Anyway good luck for the up coming season.. I guess your car will be full tube chassis like the CRX is.. Hmm to be the first 10sec all motor with a full stock chassis set-up would be cool..

online
15-08-2005, 09:49 AM
our new car is just a H22A powered Gen 2 Full Body CRX. It is still early stages so we will happy to run in the 11's and slowly work on the 10's from there. Yeah it's a shame not many are building cars like these as you and i know how much fun they are. all the best in running the 10 as i'm sure it will just inspire us to run faster :thumbsup: I'll have some pics of it posted pretty soon. :)