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View Full Version : 1/4 mile gear changing



HOK
07-09-2002, 02:03 PM
I just thought of something maybe you guys can help....

i always hit the rev limit JUST at the beggining of the end of the 1/4 so i lose a lot of time trying to chnage into 5th which i never get in anyways cause i miss it... i tried even changing each gear earlier and still was just done letting the clutch out and the 1/4 was done... you know wha i mean? i'm in neutral for the last second or two trying to make these huge throws... (clutch in UP all the way RIGHT PUSH UP! grrrr) yes i suck.. help me out...

rage2
07-09-2002, 02:09 PM
You hit 5th at the end of the 1/4 mile? Tha'ts pretty short gearing. What car?

HOK
07-09-2002, 02:12 PM
umm the impreza... RS... yea it is short... my buddy's WRX is only half way done 4th at the end of the quarter... HELP!

HOK
07-09-2002, 02:24 PM
you think the difference is small since i have the momentum going with the car anyways?

B18C
07-09-2002, 02:36 PM
Shift into 5th! What are your trap speeds?!?! I kind of have the same problem but it's with 4th gear.

You can try going to a bigger wheel diameter.

Redlyne_mr2
07-09-2002, 02:40 PM
dman dude 5th, I'm at the top of 3rd when I reach the end

2K255HP
07-09-2002, 05:40 PM
ya i thought most cars finish near the top of 3rd
i know the maximas and altima's do :dunno:

Ekliptix
07-09-2002, 05:51 PM
I have to shift into 4th, but once I kept it in third and bounced off the rev limiter(that was the only time ever).

If I were you, I'd try shifting into 5th and see what you're time is.

4wheeldrift
07-09-2002, 06:16 PM
Are you running the car right up to the redline in every gear?

border_project
07-09-2002, 08:33 PM
wow
its like a real rally transmission setup

2000impreza
07-10-2002, 09:15 AM
i replied over at the other forum. you need more rpm's. your running the 2.2l bottom end, it can handle up to 7000rpms. aftermarket ecu will fix that. you might be able to get 500-600 more rpm's over stock redline(6250). since your running 2.5l heads you can't go much higher than stock redline because you will start to float your valves with a higher redline and too much boost. either way i think you hit a very expensive wall. hehe. look for some sti heads maybe??? :confused: $$$$$:bigpimp:

with all that being siad you will probably need a new tranny shortly too if your running that much power.

HOK
07-10-2002, 12:02 PM
grrr... i don't know... i'm running redline in all gears... top speed in our cars is 245 kms... i took it to that limit... but what is the top of 4th..? because i have good times and my MPH is WAY down... andd some of my buddies are saying cause i'm sitting there shifting and losing all the speed while in neutral... i have been over the 101 mph once... i usually have 99mph or 98... i tried planting it at the end once and it was just like being in neutral for 2 seconds..

HOK
07-10-2002, 12:06 PM
bigger wheel diameter... thats one i havn;t thought of... i tried shifting into fifth while i was 1000 rpm before redline and it was pretty bad....

i don't really want to change the ECU anytime soon... cause the car works really well... and there are no CEL lights so i'm really comfortable with the setup... if i get new heads... it won't just be ecu and heads heheheheh prolly get new everything and try for 350 whp.. maybe... RA tranny etc... sweeet

B18C
07-10-2002, 12:06 PM
Go to a bigger wheel diameter (ie. get a higher series tire), if you have a set of wheels you use for racing.

HOK
07-10-2002, 12:19 PM
coo need to get wheels anyways... i was thinking of getting 18s stockers are 16's.... do you think i will be just hitting redline in 4th then with 18s?

2000impreza
07-10-2002, 01:22 PM
this might be useful in helping you find the right size. don't go too wide in size cause there isn't much clearance in the rear with the fenders.

http://www.miata.net/garage/tirecalc.html

TomTom
07-10-2002, 04:45 PM
i was just throwing it into 4th at the end of the 1/4 mile doing 85mph

4wheeldrift
07-10-2002, 05:46 PM
You should be right up at the top of fourth with a 101mph trap speed. If you are optimizing the car for 1/4 mile, your best bet is probably to go to a slightly taller tire. The better solution would be to get an ECU that doesn't have the low rev limit (even another 250 rpm or so would do the trick)

HOK
07-11-2002, 12:45 AM
man 250 rpm.. is there a really cheap way to take out the rev limit... but then i won't have fuel and timing maps in the stock ecu... god... i'm thinking just forget about it... cause this is costing too much lol

4wheeldrift
07-11-2002, 06:55 AM
Just put a CVT in the car, that will solve all your problems (except the cost one, of course :))

Davan
07-11-2002, 08:53 AM
I too am at the very very top of 3rd at the end of the quarter. I was running 16.4's throwing it in 4th gear. Got it down to 16.1's holding it in 3rd. Mind you, I'm only trapping at 86mph. If I get faster, and actually need 4th, I guess I'll just be getting slower again? :dunno: