Quarter mile tips and info!?

[MM BOOST]

Couldn't find a dedicated forum talking about 1/4 racing, so i figure'd I'd post it here.

Alright here is the deal. I've been challenged locally from an old buddy of mine who has a new cobalt turbo that has been talking MAD s***. he has an intake, cut off muffler and he "says" a mail in tune. He is not the best driver and he ran a 14.5 at Bristol Motor Speedway last season. I've never been down the strip, but I am answering his challenge and wanting to figure out the do's and don'ts to the mazdaspeed 3. I am trying to figure out the best way to launch the car and best points to shift. My guess is I want to keep it in its efficiency range, so shifting around 5800 rpm's.

Here is my setup

-injen cai
-medieval turbo inlet
-forge bpv
-street unit boost tubes
-turbo xs stealth back with stock exhaust modded (one resonator and the muffler removed)
-denso 1 step colder plugs
-trz rear motor mount
-h&r springs
-twm short shifter and bushings
-18x8 wheels with 235/40/18 tires

Any advice, tips or info? I am fully aware the cobalts are a hair bit quicker, but I have quite a few things that I am sure would equal the playing field as long as I can drive the car correctly. He has been talkin mad s*** for months and I haven't said a word...but my father used to drag race for a while locally and won many tournaments, so he is gonna spend some time with me in 2 weeks showing me what I should and shouldn't do. It will help knowing the best things to do and not do with the ms3 to get THE best possible time.

 

[Circle9]

I got a 14.0 with bald tires and a stock car. I imagine that you'd at least be able to do the same

With the tires you have, I suggest slipping the clutch in at 3000-3500 and shifting at about 6000.

The only way the Cobalt beat the MS3 in the 1/4 in magazine comparisons was by using it's no-lift-shift feature.

 

[MM BOOST]

so slip the clutch, don't just dump it? What about letting out air in the front tires to help traction? I also heard about running with just about a quarter tank of gas for weight purposes.

 

[Circle9]

Yes, slip the clutch in, if you dump it you'll just spin the tires. Let the car start moving a little before dropping the clutch in the rest of the way.

Correct, you want to race with less than have a tank of gas for weight reasons. Run the front tires at around 26-28 psi, and the rears at 36-38 psi.

With your tires, I don't think you'll encounter half as much difficulty trying to hook as I did.

 

[blackdragon0731]

in addition, remember what he said about the no-lift shift.. thats gonna give him the advantage of almost no power loss at all, from that turbo being constantly spooled especially... as far as our cars go, we have more torque, especially with the mount you have in there and that intake, you won't have wheel hop with the mount, all your torque will go straight to the street. you shouldnt have a problem as long as you keep calm

 

[MM BOOST]

I am pretty excited to run. I think the downpipe and turbo inlet and colder plugs will help the car breathe a hell of alot better. Pretty much no restrictions anywhere on the intake or exhaust side of the turbo. Just the stock top mount (which will be upgraded to a SU along with cobb ap soon) . I am going to have to practice coming off the line at 3 grand without dumping the clutch. Thanks for the help, everyone else please chime in if you have anymore advice.

 

[SubieKiller3]

Couldn't find a dedicated forum talking about 1/4 racing, so i figure'd I'd post it here.

Alright here is the deal. I've been challenged locally from an old buddy of mine who has a new cobalt turbo that has been talking MAD s***. he has an intake, cut off muffler and he "says" a mail in tune. He is not the best driver and he ran a 14.5 at Bristol Motor Speedway last season. I've never been down the strip, but I am answering his challenge and wanting to figure out the do's and don'ts to the mazdaspeed 3. I am trying to figure out the best way to launch the car and best points to shift. My guess is I want to keep it in its efficiency range, so shifting around 5800 rpm's.

Here is my setup

-injen cai
-medieval turbo inlet
-forge bpv
-street unit boost tubes
-turbo xs stealth back with stock exhaust modded (one resonator and the muffler removed)
-denso 1 step colder plugs
-trz rear motor mount
-h&r springs
-twm short shifter and bushings
-18x8 wheels with 235/40/18 tires

Any advice, tips or info? I am fully aware the cobalts are a hair bit quicker, but I have quite a few things that I am sure would equal the playing field as long as I can drive the car correctly. He has been talkin mad s*** for months and I haven't said a word...but my father used to drag race for a while locally and won many tournaments, so he is gonna spend some time with me in 2 weeks showing me what I should and shouldn't do. It will help knowing the best things to do and not do with the ms3 to get THE best possible time.

he is deffinately not a good driver. your friends car is suppose to do 14.0 all stock. you should be running mid 13's with the set up you got. get yourself tuned and you will do even better than that. so go spank em' boy!

 

[PCspeed3]

turn off the boost limiter and launch it from 2nd.....lol I have always wondered if this would work...... just make fun of his porta potty interior quality if he beats u haha

 

[LordWorm]

without working your gearing out ....i'd hazard a guess your best results will be gained if you shift at the redline. Yes you'll be falling off the power curve, but most look at the powercurve to work out what the best shift point is, and neglect GEARING. On a G-series box with just about any dyno graph i've ever seen, the calculated shift points are so high above redline it isn't even funny - you achieve a greater amount of wheel torque/static thrust by staying in gear as long as is practical - which means running it right up as close to the redline as you dare.

If you have adjustable shocks, stiffen them up to alleviate weight transfer to the back of the car on launch.

Try and launch at peak engine torque if possible - only go lower if you can't get traction.

do not launch from 2nd - the torque multiplication effect is greatest in 1st - even with half the power, you'll accelerate faster out of 1st than second.

try preloading against the e-brake, get the car staged, pull the e-brake hard, and lift the clutch until its right in the middle of the friction point....drop the e-brake, slip the clutch, and apply the throttle in one fluid motion - preloading will help protect the driveline against sudden shock, and prevent some of the nasty weight shift.

I run my front tires very soft (basically as low as i can without it riding on the side walls, and push the rear tires up as high as the tire manufacturer recommends as maximum. this gives you grip where you need it (driven wheels) and minimum contact patch where you don't (rear wheels that are along for the ride). It also helps to angle the car forward, which gets weight over the front wheels and helps plant the nose.

Remove any extranious body work - rear wing, front lips, etc - this stuff creates large amounts of drag. Rear wing taken off my protege alone dropped my PB quartermile time by 0.2s.

 

[MM BOOST]

Very informative post my friend, thank you so much. The tire pressure will definately be something I do. Body is stock other than window visors and a towhook license plate. The pre-loading thing might be a stretch for me, thats alot to remember for a first timer, haha. I will try your advice on shifting at redline and maybe try that once, and then try it once with shifting before.

 

[LordWorm]

Very informative post my friend, thank you so much. The tire pressure will definately be something I do. Body is stock other than window visors and a towhook license plate. The pre-loading thing might be a stretch for me, thats alot to remember for a first timer, haha. I will try your advice on shifting at redline and maybe try that once, and then try it once with shifting before.

think of preloading like hill starting, without a hill...you actually preload everytime you take off at a hilly intersection...you apply the e-brake, you pull the clutch out, give it some revs, and let it all happen when you're ready to move...only difference here is no hill, and a crapload more RPMs.

don't think of the lights if you're a first timer.. who cares if you cut a 2 second reaction time...just practice launching... lights can be stressful and if you're trying to cut a good light, without any technique, you're going to screw it up. once launching becomes second nature, and you can do it the same way every time without even thinking about it - THEN you can go play the RT game... remember, a good time is often measured by a good 60ft time...the first 60ft is really the only part of a run that you have any sort of control over...so getting the launch right is critical to running a good number.

if the car has a factory rear wing, i recommend removing it for drag racing along with your other normal weight reduction (spare tire needn't come for a ride on the 1320', neither does your tool kit, big stereo...or even back seats!). The reduction in drag will make a big difference in the ET, and factory wings are neither aerodynamic, or required at the kinds of speeds you are doing.

Another thing to look at if you get serious are spring clamps - since you don't have coilovers and cant lower the car, spring clamps on the front increase the drop by the gap between 2 of the spring coils - and increase it by the same on the rear. You still get suspension travel, but by getting the back of the car up and the front of the car down, even slightly, you will have far more traction at your disposal.

Deactivate any sort of traction control devices - not only are these illegal in many drag racing events (if you decide to compete, you don't want to have practiced with active traction control and then not be allowed to use it when its time to race), but many tcs systems rely on cutting power to the driven wheels when they start to slip - a little bit of wheel slip is a good thing on the drag strip, and having the power there is far better than not.

above all practice. noone can tell you what works for you - thats something you have to work out for yourself - i've given you all the tips i can think of to improve your times from a purely mechanical stand point - but other things like whether to flat shift or not (if you're going to flatshift at redline, i would recommend getting a flatshift box to cut ignition when you do it, so you don't rattle off the limiter between shifts), how much clutch slip you need (i use enough to keep the revs on the motor up during launch, but then i dont have a turbo so i dont need to worry about the wheels breaking away from me) etc etc is going go be down to how you drive and what is the most comfortable for you.

Most importantly - have fun with it...drag racing is an awesome, affordable and safe form of racing...get out there and enjoy your car on the strip whenever the opportunity presents itself

by the way - i believe some of the aussie guys have had their speed3's into the high 13s on near stock cars - so theres plenty of potential there

IMPORTANT EDIT: just noticed your father used to race and is going to coach you - this will be good for race strategy etc - BUT i assume he raced RWD cars, and if so alot of what he is going to tell you wont translate...RWD lives for weight shift (plants the rear of the car etc).

Oh and drive around the burnout box....no need to get your tires wet or do a burnout on street rubber unless the pit area is just a grass paddock, then a short sharp burnout to scrub the tires might be beneficial.

 

[Circle9]

He is not the best driver and he ran a 14.5 at Bristol Motor Speedway last season.

If that is all he ran, you should have no problem at all even if you are just an average driver. Did he achieve that time while using no-lift-shift? 14.5 is what the Cobalt SS/SC or a Si with a intake and header can do.

 

[240ka]

My best with bov, intake and springs is is 14.4. Yeah I suck. My friend got in my car for the first time and ran a 14.1. I want to learn as well

 

[240ka]

Spark plugs make a big difference? Which plug to get?

 

[MM BOOST]

Thank you so much for the tips and hints man, very very informative post!!!

 

[MM BOOST]

I had one more question...will I be keeping it in 4th and maxing out 4th by the time I cross the line? Or will I have to hit 5th? Not sure with the gearing on this car, so that's why I ask.

 

[blackdragon0731]

well running a 14 ish time youre gonna be around 100... youll probably hit 5th

 

[MM BOOST]

anyone else chime in? ive heard both...

 

[LordWorm]

theres plenty of online calculators out there that let you put in your gear ratios and tire sizes, along with redline RPM, to calculate peak speed in each gear.
if you need to use 5th, use 5th.

 

[MM BOOST]

ok thanks man, you've provided alot of help and insight. Time to take the car out and practice.