Swap 1/4 Mile Thread

[justin_l_]

nice time, I'm guessing with the 2.93 you only had to shift twice? anything done to the chassis to make it lighter?

Oops, I lied. I was running the stock 2.79lsd. With the getrag 250 it seems more like having a 260 with something between a 2.93 and 3.25lsd. I got into 4th by the end of the track, prolly around the 1000ft mark.
As for weight, not much. Took the tar out of the trunk and the padding out from under the carpet because it was gross. No spare tire or jack. I think I could have gotten a couple tenths off if I had good subframe bushings. Wheel hop was horrible, sounded like something was going to break so I kept letting off.
Hopefully next year I will break into the 13's. Replacing my subframe bushings, chip should be in soon and will get a good set of tires instead of some free junk, although I didn't really have any issue with traction.

[416stroker]

Thanks Matt!



If its just traction, thats easilly fixable with correct suspension tuning and tires. I only really have traction issues on cold cold days.

Ya most of the setups are to stiff so the car cant weight transfer.

what size slicks are you running bmwsob?

[BMWSOB]

^ Fucking awesome man!

Thanks Matt!

yeah those are really good times for the m50nv... makes me hopeful that i really have a high 12 sec car if i could apply power to ground

I would have to guess that most of these low 1/4 tires are more due to lack of overall traction than lack of power.

If its just traction, thats easilly fixable with correct suspension tuning and tires. I only really have traction issues on cold cold days.

[BeirBrennerE30]

nice time, I'm guessing with the 2.93 you only had to shift twice? anything done to the chassis to make it lighter?

yeah those are really good times for the m50nv... makes me hopeful that i really have a high 12 sec car if i could apply power to ground

I would have to guess that most of these low 1/4 tires are more due to lack of overall traction than lack of power.

[nando]

M50 nv, getrag 250, 2.93lsd junk tires for drifting. Stock engine w/146k, stock ecu, 2.5" exhaust.
R/T .480
60' 2.193
330 6.009
1/8 9.314
MPH 76.37
1/4 14.427 @ 96.64 MPH

nice time, I'm guessing with the 2.93 you only had to shift twice? anything done to the chassis to make it lighter?

[justin_l_]

M50 nv, getrag 250, 2.93lsd junk tires for drifting. Stock engine w/146k, stock ecu, 2.5" exhaust.
R/T .480
60' 2.193
330 6.009
1/8 9.314
MPH 76.37
1/4 14.427 @ 96.64 MPH

[MR 325]

^ Fucking awesome man!

[BMWSOB]

With the bugs worked out and some more power i think so. Nothing a little nitrous cant help... Hopefully getting the chassis squared away for a 8.50 cert.

[416stroker]

In that pass, the clutch was slipping pretty bad. I had to pedal it a little in third to get the clutch to grab. Then in forth, once boost crept up close to 40, the clutch was overpowered fully engaged. It was still accelerating, thats why I stayed in it till I crossed the line. Very far from optimal. I have a twin disc with sintered bronze discs, Its probably time for an upgrade at this point.
More info here http://forums.bimmerforums.com/forum....php?t=1128098

And I also have a vid of what happens if its cold and i don't heat the tires enough.

http://www.youtube.com/watch?v=VgnUYxXPBoQ

Donovan

Think you can get down to the high 8's with all the bugs worked out.

[BMWSOB]

In that pass, the clutch was slipping pretty bad. I had to pedal it a little in third to get the clutch to grab. Then in forth, once boost crept up close to 40, the clutch was overpowered fully engaged. It was still accelerating, thats why I stayed in it till I crossed the line. Very far from optimal. I have a twin disc with sintered bronze discs, Its probably time for an upgrade at this point.
More info here http://forums.bimmerforums.com/forum....php?t=1128098

And I also have a vid of what happens if its cold and i don't heat the tires enough.

http://www.youtube.com/watch?v=VgnUYxXPBoQ

Donovan

[416stroker]

Sorry, don't mean to be mean, but that's a such a novice statement. If you knew anything about drag/flooring a high hp car and optimizing each gear with great power you'd understand the reason of a revlimiter and the reason why he's on it a lot. If you didn't notice he's pushing out a lot of power, meaning before he even reaches the maximum speed for each gear he's already spinning his tires. So while they are spinning you basically either feather the gas or just stomp on it and wait for your car to actually catch up to speed for that gear, hence why he bounces off the revlimiter. If he were to shift gears ever time he hit redline immediately he would bog out the next gear (something you would apparently do) and get even slower times.

I have probably more experiance with drag racing most people here. I have made passes in the 10 second range and your full of it haha id like to know where you learn your shit. How than the car keep pulling when your bouncing it off the revlimiter? He wasnt Spinnig at around half track when he was on the rev limiter

also he only spun bad in first and second i know that... he might even get in the 8s if he can get that under control.


Edit: I was try to be an ass to him the car is fast and has the possabality to be even faster.

[golde30]

Not to mention that the 20hp gain barely negates the added weight of the 24v motor.

i believe this has been addressed multiple times, the 24v motors are only like 50lbs heavier than the m20...

[rThor432]

it's going to take a lot more than 20hp to shave a full second off the 1/4 mile.

Not to mention that the 20hp gain barely negates the added weight of the 24v motor.

[golde30]

I guess I've just come to expect dissapointment. there are so many exaggerated claims of power and acceleration you pretty much have to expect it to be not quite as fast as you thought. The truth always hurts a bit; when people go from their imaginary race times (dude I totally just smoked a viper light to light!) and then go to an actual track they don't like what they get because the clock doesn't lie.

word.

my s50 was low mileage, but i rebuilt it and when i took it to the drags, i expected low 14 to 14.0, best run was a 14.5. with my m20 my best time was a 15.9 i believe, so i was kinda happy, but at the same time depressed that $8kish got me only 1.5sec faster.

[jahnaboi]

And if you wernt on the revlimiter so much you would run a low 9

Sorry, don't mean to be mean, but that's a such a novice statement. If you knew anything about drag/flooring a high hp car and optimizing each gear with great power you'd understand the reason of a revlimiter and the reason why he's on it a lot. If you didn't notice he's pushing out a lot of power, meaning before he even reaches the maximum speed for each gear he's already spinning his tires. So while they are spinning you basically either feather the gas or just stomp on it and wait for your car to actually catch up to speed for that gear, hence why he bounces off the revlimiter. If he were to shift gears ever time he hit redline immediately he would bog out the next gear (something you would apparently do) and get even slower times.