Launch control and slicks
#1
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Launch control and slicks
I’ve been to the drag strip a few times with my Miata but didn’t have good luck messing with launch control on street tires (RS2’s). It would either bog or I ended up getting lots of wheel spin or wheel hop so after a few tries I went back to slipping the clutch. I still would fight wheel spin and most 60’ times were around 2.3. My best was 2 seconds flat but that was a fair amount of clutch slip and after that the stock clutch did not want to grab too well the rest of the day.
This year I’m going to be running drag slicks. I’ve never launched anything on slicks before and don’t really know how hard they will bite or if I will still get wheel hop. Slicks are 24.5x8.5x15 and are not radials and I’m also running a pucked clutch. I’d like to see how other people are launching and come up with a strategy since I’ll only get a few chances to try at the track.
So who uses launch control? Slip or dump clutch? What RMP are you launching at? What’s your best 60 foot? Will the softer slicks cause less wheel hop?
This year I’m going to be running drag slicks. I’ve never launched anything on slicks before and don’t really know how hard they will bite or if I will still get wheel hop. Slicks are 24.5x8.5x15 and are not radials and I’m also running a pucked clutch. I’d like to see how other people are launching and come up with a strategy since I’ll only get a few chances to try at the track.
So who uses launch control? Slip or dump clutch? What RMP are you launching at? What’s your best 60 foot? Will the softer slicks cause less wheel hop?
#4
One day we had our autox timing equipment set up at a launch station during a school we were putting on. I used that to set up my launch control. I dont know the distance so its irrelevant. The best I could do without the launch was 2.5 seconds, with it I did 1.8 consistently and so did my girlfriend. I could have turned the launch RPM up a little more as I was still slightly bogging but I was happy with it. The nicest thing about launch is the consistency of your launches. Of course I do not drag race, only autox so its a pretty different scenario.
This was on RS2s as well.
This was on RS2s as well.
#6
wheel hop is all dependent on tire pressure and suspention settings. there is no perfect formula, its all practice and trial and error. the purpose of launch control/2step is so you dont need to focus on holding your revs. you can concentrate on the tree better.
your tire pressure is gonna be key, and getting the slicks hot in the burnout box. your prob gonna wanna start out with 10psi or so in the tires. and just play with it. but i recomend launch control so you can focus more on what is happening. being consistant is the name of the game.
i dont drag my car, but i work for an engine shop that builds alot of pure drag engines and my boss and his wife are both hardcore racers. so i have learned alot from them
your tire pressure is gonna be key, and getting the slicks hot in the burnout box. your prob gonna wanna start out with 10psi or so in the tires. and just play with it. but i recomend launch control so you can focus more on what is happening. being consistant is the name of the game.
i dont drag my car, but i work for an engine shop that builds alot of pure drag engines and my boss and his wife are both hardcore racers. so i have learned alot from them
#7
I have had tire preasures from 8lbs to 20lbs, and never had a problem with wheel hop on slicks. Radials on the other hand, I am about to have to spit my broken teeth out after a launch.
If you have launch control, great. But if you don't have it, you can still cut a good light and have a good 60'. Practice.
If you have launch control, great. But if you don't have it, you can still cut a good light and have a good 60'. Practice.
#8
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Well if you have slicks and a pucked clutch then rev it all the way to redline and sidestep your clutch. FWIW I do say go with launch control but not megaboost- like 5psi. I say save that for the last drag of the day because **** will break from the mad torque transition.
I assume you are asking for GRM competition strategy? I think it's super awesome that you have entered and placed so high already. You are a celebrity!
I assume you are asking for GRM competition strategy? I think it's super awesome that you have entered and placed so high already. You are a celebrity!
#9
I have had tire preasures from 8lbs to 20lbs, and never had a problem with wheel hop on slicks. Radials on the other hand, I am about to have to spit my broken teeth out after a launch.
If you have launch control, great. But if you don't have it, you can still cut a good light and have a good 60'. Practice.
If you have launch control, great. But if you don't have it, you can still cut a good light and have a good 60'. Practice.
Having launched n/a cars and f/i cars I'd say the difference is SIGNIFICANT in the amount of effort to get an f/i car in that "perfect spot" of not bogging and not spinning. The torque onset is nowhere near as predictable as n/a. sure the slicks will definitely help not spin or hop, but its still a bitch to not bog.
Launch control simplifies that greatly, and takes out one more variable: lag.
Just sayin
#14
I use a set of BG Goodrich drag radials and have my launch control set to 4500RPM, and i make 4 psi of boost while there. My last drag race session with launch control was my absolutely most predictable session I ever had.
I think one of your main problems is that your launch control probably isn't making any boost. Fix this and you will not bog at all.
Secondly, you need to get rid of the stock clutch.
I think one of your main problems is that your launch control probably isn't making any boost. Fix this and you will not bog at all.
Secondly, you need to get rid of the stock clutch.
#18
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I first set launch control at 4000 RPMs and moved down from there. It made about 5 psi and with street tires I just did not have the traction. I tried lowering it to about 3000 and it would either grip and bog or spin tires. Maybe with a little more time I could have found a sweet spot. Also with the EBC boost hits like a hammer. The car can grip then break loose as it spools. I might try a MBC or switch the EBC off in first and run wastegate pressure. Something I can mess with later since I don’t want to add too many variables. Also rear diff has been upgraded to 7” with an RX7 LSD shimmed with a beer can.
Ha, this would be GRM competition strategy. I start my runs at 8 psi and make sure I get a time slip then start adding more and more boost. Last year I got up to 19 psi out of the 14b but I did not go any faster then when I was running 15 psi. 19 just made the clutch slip more and blow hot air up top. This year I’m running a 60 trim T3 and maybe a 50 shot of nitrous. Yes, I know the rods might not like this.
Ha, this would be GRM competition strategy. I start my runs at 8 psi and make sure I get a time slip then start adding more and more boost. Last year I got up to 19 psi out of the 14b but I did not go any faster then when I was running 15 psi. 19 just made the clutch slip more and blow hot air up top. This year I’m running a 60 trim T3 and maybe a 50 shot of nitrous. Yes, I know the rods might not like this.
#19
I first set launch control at 4000 RPMs and moved down from there. It made about 5 psi and with street tires I just did not have the traction. I tried lowering it to about 3000 and it would either grip and bog or spin tires. Maybe with a little more time I could have found a sweet spot. Also with the EBC boost hits like a hammer. The car can grip then break loose as it spools. I might try a MBC or switch the EBC off in first and run wastegate pressure. Something I can mess with later since I don’t want to add too many variables. Also rear diff has been upgraded to 7” with an RX7 LSD shimmed with a beer can.
Ha, this would be GRM competition strategy. I start my runs at 8 psi and make sure I get a time slip then start adding more and more boost. Last year I got up to 19 psi out of the 14b but I did not go any faster then when I was running 15 psi. 19 just made the clutch slip more and blow hot air up top. This year I’m running a 60 trim T3 and maybe a 50 shot of nitrous. Yes, I know the rods might not like this.
Ha, this would be GRM competition strategy. I start my runs at 8 psi and make sure I get a time slip then start adding more and more boost. Last year I got up to 19 psi out of the 14b but I did not go any faster then when I was running 15 psi. 19 just made the clutch slip more and blow hot air up top. This year I’m running a 60 trim T3 and maybe a 50 shot of nitrous. Yes, I know the rods might not like this.