Please help with 60ft times...

[luvdriven540i]

Hello all, :help

I'm new to the drag strip. My car is a stock 98 540/6 with 65k miles, minus about 120 lbs.

After nine runs, my ET ranged from my first run of 16.546 (ok, you can stop laughing now) :lol with a 60' time of 2.606.......to my last run of 14.690 with a 60' time of 2.343.

I know it's lame, but I am improving. What is a decent 60' time for that car?

The 235/45-17 General Exclaim UHP tires are spinning like crazy even with a launch of 1500 rpm's. I'm sure to go around the water, and I haven't tried a burnout yet.

Please give suggestions on better launch techniques and the best tires and size. The tires could be strictly drag tires that will be changed at the strip or a good drag street tire.

Thank you, all the best!:buttrock

(http://www.tirerack.com/tires/tires.jsp?tireMake=General&tireModel=Exclaim+UHP)

[Grimmjar]

do you have a LSD?
LSD or Slicks will help alot, both are perfect for the beginning.

http://www.dragtimes.com/BMW--540i-Drag-Racing.html

[HKS]

I suggest you to get a pair of drag slicks (Mickey Thompson ET Drag, Hoosier, ..) and your 60" times go under 2.0 with no problem.

My opinion is there is no point to mess with street tires or some kind of circuit slicks.

[ltw97m3]

contrary to popular belief about how tangible a proper run is to come by there are many factors outside the tires on your car that could have effected your outcome. drag radials and slicks take much less logistics for a pass in which you get a proper 60'. but lets evaluate your current setup. id start by dropping your air pressure in the rear tires to 25psi. and depending upon the results maybe continue to lower the psi to as far down as 17psi or so. air pressure it's self has the ability to solve the traction issue your having; be prepared the car may seems floaty and unstable on the top end of the track.

the next area to address is the water pit. id also venture a guess that either you still have water on your tires or the asshole before you left residue water down on the most important part of the track in regard to e.t. on street tires id recommend everyone to take this potential problem out of play and just go around the water pit. with the burnout smoke the tires till you see some thicker smoke within your side view mirrors. also if you cant avoid the water just roll through it, i see a lot of people staying in the water during their burnout. just get the tires wet and roll out and drop the hammar just outside of the water. the reason i mention doing the burnout even for a little longer with street tires because that should provide the speed and heat to expel most water trapped within the tires.

lastly dont imagine the gas pedal as an on/off switch its entirely variable. i can understand the discipline one must observe to not go wide open as the adjacent lane is running away from you; but often part throttle will offer some saving face. but im not entirely convinced that the part throttle solution plays at all into your problem. again if i had to guess id imagine that water is creating less grip by either your doing or the racer before you. so avoid it altogether.

here are 2 videos and a description to help you with launching.

1) make sure if you go through the water that it all comes off your tires before you leave the line. also people that go before you could potential create a problem with residual water down in your lane, try and be aware
2) tire pressure and tires themselves are very important and can make the task of launching the car closer to second nature. i have a feel for about how much acceleration my tires can take just before they break lose(my anxiety often clouds my judgment though).
3) just stay with the clutch a little while after leaving the line and make a smooth transition into all throttle...that transition into full throttle needs to be made longer as the rpms in which you launch at and power to weight ratio decreases. for example....this is important to understand....if i launch my car at 2000rpms i can get off the clutch and go wide open throttle very soon after my cars gains momentum...on the other and if i launch my car at like 5000rpms ill have to stay with the clutch much longer to ensure when i lift off the clutch my tires dont break lose. in the latter scenario image if i let off the clutch at like 5mph...essentially it would have a similar effect to that of a clutch kick to induce lose of traction.
here is an example where i had a feel for threshold of the tires. in this video i launched way to high so i had to stay with clutch longer in order to prevent tire spin. that day i shot that video temperatures were in the 3x's and with those same tires because people think tire spin is indicative of power:rolleyes i could spin 2 completes gears so that when i shifted into 3rd i was actually traveling 60mph.
http://www.youtube.com/watch?v=JZB6JCvroyw
4) here is another common mistake people make.
people will often shift as soon at they break lose. if your car dosent have much momentum and has enough power it will just spin you in second gear as well. most of the time if you had the proper momentum that the first gear would give you(i.e. bottom of 2nd after a redlined 1st is ~30mph for me) the car would never break lose at those speeds.
here is a video of me with a terrible launch...i launched high and got off the clutch before i had enough momentum thus inducing wheel spin(as i described above) and only smart thing i did was ride out 1st gear...had i shifted right away i would have easily spun 2nd gear.
http://smg.photobucket.com/albums/v661/ColoradoZQ8/Sac%20raceway%203-20/?action=view&current=VideoTape2008_03_20_15_34_05.flv

[luvdriven540i]

Thank you all for the input...


do you have a LSD?
LSD or Slicks will help alot, both are perfect for the beginning.

I don't have an LSD, just the stock 2.81 open diff...


fishforlife.....hey, thanks for the videos, even with the disappointing launch, you beat that Integra handily. (I think it was an Integra.)

Anyway, I did have 25 psi in the back tires and 45psi in the fronts. I'll try around 20 psi next time. (10/16) although, I may have different tires by then.

I read in another post by MrBlonde, that it is better to go with a smaller diameter rim with a higher profile tire. I don't want to misquote him. I can't find the post, but I was hoping he would chime in. He also seems very knowledgeable on the subject......thanks again everyone, all the best...

[quote=HKS;17579435]I suggest you to get a pair of drag slicks (Mickey Thompson ET Drag, Hoosier, ..) and your 60" times go under 2.0 with no problem.

My opinion is there is no point to mess with street tires or some kind of circuit slicks.


How about the
http://www.tirerack.com/images/tires/bfg/logo_bfg.gif (http://www.tirerack.com/tires/bfg/bfgoodrich-tires.jsp)g-Force T/A Drag Radial?

http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+T%2FA+Drag+Radial

[MrBlonde]

I read in another post by MrBlonde, that it is better to go with a smaller diameter rim with a higher profile tire. I don't want to misquote him. I can't find the post, but I was hoping he would chime in. He also seems very knowledgeable on the subject......thanks again everyone, all the best...

Click on the links in my sig for more info

[luvdriven540i]

Thank you, Kenny...

Kenny, I read, "Best Rubber Fitment..." from your sig., but it doesn't mention the e39.

Do you happen to know what the tallest and widest setup I can fit in the well and around the brake on the 98 540/6? (unmodified)

Right now I have 235/45-17's all around, with an overall diameter of 25.3". I want to get a separate setup for the backs that will be used for the drag strip only.....thanks again.....

[ltw97m3]

the tallest, widest tires can also reach points of diminishing returns so keep that in mind too. i was lucky to find that a 225/50/15 works with my car and provided every bite of traction i will likely ever need. the plus side to using suck a small tire compared to stock is it helped my gearing immensely. so not only do i have traction i have my car pull like i have a 3.38 diff with stock sized tires.

[creeves328]

the tallest, widest tires can also reach points of diminishing returns so keep that in mind too. i was lucky to find that a 225/50/15 works with my car and provided every bite of traction i will likely ever need. the plus side to using suck a small tire compared to stock is it helped my gearing immensely. so not only do i have traction i have my car pull like i have a 3.38 diff with stock sized tires.

Good stuff Fish!!

Another thing to add about using 225/50/15's, the tire is lighter, and this is the most beneficial area to target for limiting rotational mass losses; at the fastest moving area.

[95s52]

Good stuff Fish!!

Another thing to add about using 225/50/15's, the tire is lighter, and this is the most beneficial area to target for limiting rotational mass losses; at the fastest moving area.

You are one of the most knowledgeable members on the forums and I respect you for all the advice you give, so I really hate to call you out on this. Although the theory above works on paper, it simply does not on the track. It's hard to explain, but I'm talking from personal experience.

[ltw97m3]

mark,
there are many variables that may explain your counter intuitive results. its not fair to call out a correlation with your tire setup and the results they yielded when the other variables have not been isolated yet. what chris has mentioned will always provide benefits that will translate into better performance the exceptions being when a variable/s produces enough lose to negate what gains the tires/wheel produce.

[creeves328]

You are one of the most knowledgeable members on the forums and I respect you for all the advice you give, so I really hate to call you out on this. Although the theory above works on paper, it simply does not on the track. It's hard to explain, but I'm talking from personal experience.

Hey, no worries dude!! I never take it personal and actually like call outs if I am incorrect. All of my stuff is computational and yes real-world can introduce variables previously unknown.


mark,
there are many variables that may explain your counter intuitive results. its not fair to call out a correlation with your tire setup and the results they yielded when the other variables have not been isolated yet. what chris has mentioned will always provide benefits that will translate into better performance the exceptions being when a variable/s produces enough lose to negate what gains the tires/wheel produce.

Thanks dude!!

I guess we could say, going with Dave's 225/50/15 example: The tire is lighter and gives a rotational mass advantage, as well as a "gearing" advantage. Heat could play a role in decreasing performance though, as the circumference is shorter than stock. I'd guess the advantages outweigh the heat disadvantage though, based on this being a drag race. A road race may result in the opposite outcome.

Interesting though..

[MrBlonde]

Good stuff Fish!!

Another thing to add about using 225/50/15's, the tire is lighter, and this is the most beneficial area to target for limiting rotational mass losses; at the fastest moving area.

No, no that's not it. The tallest and widest tire that will fit.

[ltw97m3]

^your recommendation becomes the trivial solution to help get traction but what you fail to understand is that smaller, lighter tires can provide traction too. traction is traction, sure the larger, heavy tires will provide traction but they will hurt performance if traction can be had with a smaller, lighter setup.

[MrBlonde]

^your recommendation becomes the trivial solution to help get traction but what you fail to understand is that smaller, lighter tires can provide traction too. traction is traction, sure the larger, heavy tires will provide traction but they will hurt performance if traction can be had with a smaller, lighter setup.

Drag racing is a simple game:

+ Make more horsepower (solve this problem)
+ Need more traction (solve this problem)
+ Break driveline (solve this problem)
+ Repeat

The easiest one to solve is making more horsepower. If your car does not make enough horsepower to require the tallest and widest rubber you can fit under your guards then you're still at step one. Come back when you've made more horsepower.

[ltw97m3]

lucky for you there are plenty of credulous people within the community to except your advice regardless of potentially hurting performance.

[95s52]

Hey, no worries dude!! I never take it personal and actually like call outs if I am incorrect. All of my stuff is computational and yes real-world can introduce variables previously unknown.



Thanks dude!!

I guess we could say, going with Dave's 225/50/15 example: The tire is lighter and gives a rotational mass advantage, as well as a "gearing" advantage. Heat could play a role in decreasing performance though, as the circumference is shorter than stock. I'd guess the advantages outweigh the heat disadvantage though, based on this being a drag race. A road race may result in the opposite outcome.

Interesting though..

I apologize for my previous out burst. I spoke out of ignorance for answers. I guess what I really desire is not an answer but an explanation. By no means am I physicist, but at the same time comprehending the basic laws has never left me scratching my head.

The scenario:

A few months back I went out for a few runs to see what were my gains from the headers I installed earlier in the year (courtesy of a member on here :cool). I went out 2 weeks back to back and was pleasantly surprised both of the times out. I trapped as high as 106.8 and ran a 13.34 with a 2.03 60'. All with 235/45 all season 17's and the car weighing it at 3080 with me in it.

Fast forward to Wednesday, November 21st. I come out with a mindset of attaining my goal with the newly acquired slicks that I got. Those bad boys are mounted on the 15" basketweave, and are 240 and 23" tall. Because the tire is a whole 2" shorter in diameter than the all season used to acquire the above times, I was eager to get take advantage of the shorter gear ratios keeping me in the meat of my power band. The wheel and tire combo is also ~9lbs lighter PER WHEEL. And finally, the improved traction both off the line and into 2nd had me confidant that my goal of breaking a 12.99, considering my previous trap, will be something that's considered "in the bag."

My first few runs of the night with the slicks were embarrassing to say the least. At first I had trouble getting all the water off the tires. Then I wouldn't get enough heat in them. Finally my last 2 runs were halfway decent and I got a few 1.8's. Leaving the line horribly, was not what was puzzling me though. It was my traps speeds with the slicks. I was consistently trapping at mid 103's. A few recent mishaps had me thinking that my car might not be running as strong as it was a few months ago. Just as I learned to use the slicks and possibly sacrificing a few 1.7's that I am confidant I would run later in the night, I threw my dd rims back on with the 235/45's on them. Instantly I picked up 2 mph. In a few back to back runs..

Which leaves me with questions that I'm entertaining answers for.

Variables:

*VERY LIMITED. I took the plunge to switch back to street tires to limit any significant changes in temperature, wind, car weight and track conditions the next time I would be out.

OP, sorry for possible thread jack.

Chris, I apologize for the aforementioned.

[creeves328]

Hey no worries Mark!! Fish-man speaks well of you, a friend of his is a friend of mine.

Your experience does seem a little unusual to me, guess we would need another test and document the variables to figure it out.

[m3chaser]

OP,

I had 235/40/18's UHP Exclaims on my 95 M3 5spd and I had the following mods: 3.91lsd, intake, catback, and chip. I would launch at 4500-5000rpms and hang on the clutch a little and roll on the throttle. That would get me a 1.9 60ft unless I got on the throttle too much which in turn would cause me to spin. I say all that to say that what you need to do is change your throttle modulation IMHO. If you are spinning really badly and you are only launching at 1500rpms then your giving too much throttle too quickly. Instead of giving 100% throttle right away try launching at 3000rpms and start out with maybe 50% throttle and then once you are out of the whole cleanly then give full throttle (this is all done in 1st gear of course). You will have to play with how much throttle you can give and how long you will have to slip the clutch. When I talk about length of slipping the clutch I am not talking a couple seconds just to clarify. You want to only slip it a half second at best IMHO.

If you do it right you will not have much tire spin and you won't bog down. You're hurting a little bit because you have a lot of weight to pull off the line, tall gears, and no LSD. However I think that if you get good at launching to where your '60 is 2.0's then you will see a loooow 14s out of your car.

Here are a couple vids of me running a year ago. The only thing I had done was M50 manifold at this time but the car did have a exhaust leak ahaha:

This run I didn't get a great launch but the tire spin was held to a minimum. I wish I had a vid of my 13.48 run but I don't.

http://i516.photobucket.com/albums/u323/jon2523/th_MVI_2952.jpg

This run was not that great, but you can see/hear how I am slipping the clutch a little, Again, the run is not that great but the idea behind slipping the clutch and rolling on the throttle is the point of these vids:

http://i516.photobucket.com/albums/u323/jon2523/th_MVI_2958.jpg

And last but not least, this run is just on the street with like a 3000rpm rev but the shifts are rather sluggis to be sure however you get the idea that you can still rev up and slip the clutch and get a little tire spin but maintain traction because you are modulating the throttle correctly:

http://i516.photobucket.com/albums/u323/jon2523/th_MVI_3949.jpg

I hope this helps!

[MrBlonde]

lucky for you there are plenty of credulous people within the community to except your advice regardless of potentially hurting performance.

I think you're taking yourself a bit seriously here old son. If you think any advice I've given is wrong, then make your argument clearly and stick to the facts.

I've been giving advice on drag racing BMW street cars here since 2002, when I was one of two people who drag raced their BMW regularly. There are heaps more people now and heaps more questions. If something I've said is wrong or misleading then I am the first person to want to know that. I want all my advice to be good advice.

[luvdriven540i]

m3chaser,

Thanks for the input and the vids. I probably won't make it back to the track until Jan., but I'll come back to this thread and talk about how it went.

95s52,

You didn't high jack the thread, but thanks for the concern.:buttrock

[OnUrleft]

I had a 98 540i/6 and I ripped 13.8's@100-101+ with just an intake. It was in the 40's outside and I had 255 something V,W rated (nothing special) with about 20% tread left...
The key to launching my pegged legged basterd was to literally lift off the clutch slightly at launch (don't let the lights make you jump off of it) until about 25mph (slipping it slightly I suppose) then slowly coming off of it fully around 25mph (give or take a few mph) while quickly flooring it. If you can find that balance you'll run good times. I remember I went 14.2-14.18-14.10.14.0-13.8-13.8 that night. After a resonator delete, exhaust, 3.15 and removal of some crap in the trunk I went 13.5's@103+ and the thing had some more left. Surprisingly a sleeper if you ask me, seats would've taken out 150lbs (putting it around 3500 I would guess) and with a 3.64 LSD, headers, pullies and proper tuning it would've gotten it to M5 E.T's without much work at all

[luvdriven540i]

I had a 98 540i/6 and I ripped 13.8's@100-101+ with just an intake. It was in the 40's outside and I had 255 something V,W rated (nothing special) with about 20% tread left...
The key to launching my pegged legged basterd was to literally lift off the clutch slightly at launch (don't let the lights make you jump off of it) until about 25mph (slipping it slightly I suppose) then slowly coming off of it fully around 25mph (give or take a few mph) while quickly flooring it. If you can find that balance you'll run good times. I remember I went 14.2-14.18-14.10.14.0-13.8-13.8 that night. After a resonator delete, exhaust, 3.15 and removal of some crap in the trunk I went 13.5's@103+ and the thing had some more left. Surprisingly a sleeper if you ask me, seats would've taken out 150lbs (putting it around 3500 I would guess) and with a 3.64 LSD, headers, pullies and proper tuning it would've gotten it to M5 E.T's without much work at all

13.5's, Nice! Thank you for adding to the thread. :alright

[OnUrleft]

13.5's, Nice! Thank you for adding to the thread. :alright

Yep, if your on a budget, throw a 3.15 in it. If your creative and really want to makes things good swap the entire rear end to an M5 w/ 3.15 LSD. If you can find a used 3.45 LSD or 3.64LSD then by all means do it. Gearing and software is how you make those cars serious sleepers

[BMWFanatic]

I had a 98 540i/6 and I ripped 13.8's@100-101+ with just an intake. It was in the 40's outside and I had 255 something V,W rated (nothing special) with about 20% tread left...
The key to launching my pegged legged basterd was to literally lift off the clutch slightly at launch (don't let the lights make you jump off of it) until about 25mph (slipping it slightly I suppose) then slowly coming off of it fully around 25mph (give or take a few mph) while quickly flooring it. If you can find that balance you'll run good times. I remember I went 14.2-14.18-14.10.14.0-13.8-13.8 that night. After a resonator delete, exhaust, 3.15 and removal of some crap in the trunk I went 13.5's@103+ and the thing had some more left. Surprisingly a sleeper if you ask me, seats would've taken out 150lbs (putting it around 3500 I would guess) and with a 3.64 LSD, headers, pullies and proper tuning it would've gotten it to M5 E.T's without much work at all

wow...so what was your 60ft on the 14.2 run and the 13.8 run?

[luvdriven540i]

m3chaser,

Thanks for the input and the vids. I probably won't make it back to the track until Jan., but I'll come back to this thread and talk about how it went.

95s52,

You didn't high jack the thread, but thanks for the concern.:buttrock

Well, I said I would come back and write about my next track experience. It wasn't in Jan of 2010 like I hoped. I wasn't able to get back to the drag strip until Dec. 3rd 2010. (Las Vegas Motor Speedway)

I changed the rear tires on my 98 540i/6 from General Exclaim, 235/45-17 to the Nitto 555, 245/45-17. The only other change was a new shift knob. (zhp)

Anyway, the temp was around the high 40's to low 50's. I had 5 runs, although I did break my last record of 14.69, I didn't get the 14 flat that I had hoped for.

My best run was a 14.335 et with a 2.141 60ft time and trapping 97.66.

I had 24psi in the rear and about 38psi in the fronts

The run before that was 14.746 et, 2.389 60ft, and 97.77 trap. The guy I ran with on this run had a slighted modded GT, (cams, compression, exhaust, and probably intake) He was running low 13's. During this run I had 32psi in the rears. The mustang dude told me to go down to 20 to 25psi, which I did, (24psi) which I guess helped me pick up 4/10's on the next run.

I could have done better if I heated the tires, but this is still new to me and I was embarrassed to try a burnout in front of the crowd. Maybe next time...

[OnUrleft]

wow...so what was your 60ft on the 14.2 run and the 13.8 run?

that was litereally the difference between a good 2.0x-2.1 60ft and a 1.9x 60ft. That .1-.2 took off about .2-.4 E.T and added some MPH. My 540 was VERY strong and also had about 120lbs out once the exhaust was added.

There's another member on here trapping 105 in his 540 with i/e/flywheel. I suspect the flywheel is the key to good times in V8 E39's. Kinda like how 328's and mostly stock E36 M3's seem it run mid 13's quit easily with flywheel. Makes em' rev like the dickens