First time on M&H Racemasters 24.5/8.5-15, looking for advice
09-27-2010, 03:58 PM
#1
First time on M&H Racemasters 24.5/8.5-15, looking for advice
Alright 2 weeks ago I went to the track and just before it started raining we were able to get a 13.814 @ 103MPH, 60 Foot was 2.067. This was with my supercharger/meth/intercooled/~13PSI of boost. We had issue with the meth blowing out spark (has been resolved).
My question is at what rpm should one be launching at with such a setup. They hook very well when launching at about 3500rpm, I think they had 12-14psi in each tire. Should I increase at which point I launch at? Is 12-14 PSI to low of a tire pressure?
Also in the pit, when I get in the water should I just do a quick little spin? Ie hold the handbrake rev the car till it spins out of the hole then give it to warm the tires up?
When I'm waiting for the light I was told to have the handbrake on and Rev the car up, that way I have a load on the car and not have the car shocked when I luanch (IE dumping the clutch). Is this correct?
Just trying to get a clear image of what needs to be done. I didn't have much time to play around last time I went.
Thanks
My question is at what rpm should one be launching at with such a setup. They hook very well when launching at about 3500rpm, I think they had 12-14psi in each tire. Should I increase at which point I launch at? Is 12-14 PSI to low of a tire pressure?
Also in the pit, when I get in the water should I just do a quick little spin? Ie hold the handbrake rev the car till it spins out of the hole then give it to warm the tires up?
When I'm waiting for the light I was told to have the handbrake on and Rev the car up, that way I have a load on the car and not have the car shocked when I luanch (IE dumping the clutch). Is this correct?
Just trying to get a clear image of what needs to be done. I didn't have much time to play around last time I went.
Thanks
Last edited by OC_Nooby; 09-27-2010 at 04:11 PM.
09-27-2010, 05:01 PM
#2
Alright 2 weeks ago I went to the track and just before it started raining we were able to get a 13.814 @ 103MPH, 60 Foot was 2.067. This was with my supercharger/meth/intercooled/~13PSI of boost. We had issue with the meth blowing out spark (has been resolved).
My question is at what rpm should one be launching at with such a setup. They hook very well when launching at about 3500rpm, I think they had 12-14psi in each tire. Should I increase at which point I launch at? Is 12-14 PSI to low of a tire pressure?
The launch rpm depends on the car and track conditions. Try to launch as high as you can without spinning. If anything lower the tire pressure. 12-14 is a pretty high pressure for a full slick. Try like 10, preferably lower.
Also in the pit, when I get in the water should I just do a quick little spin? Ie hold the handbrake rev the car till it spins out of the hole then give it to warm the tires up?
You want to roll through the water box and then stop when your front wheels are slightly past the box. Don't stop in the water, because once you start your burnout, water will sling up into the wheel wells and drip down on the tires when you are going to stage. I found the best way is to rip the ebrake and do a 2ND gear burnout. You will heat up the tires much more efficiently with a 2nd gear burnout. Hold for like 3-5 seconds and drop the ebrake and ride it out.
When I'm waiting for the light I was told to have the handbrake on and Rev the car up, that way I have a load on the car and not have the car shocked when I luanch (IE dumping the clutch). Is this correct?
Just having the ebrake on will not load up the car. In order to preload the car, you have to have the ebrake on and release the clutch to just about when it engages. This is hard on the clutch though. I always slip the clutch out quickly, never really do a complete dump.
Just trying to get a clear image of what needs to be done. I didn't have much time to play around last time I went.
Practice makes perfect. If you have someone take video of your whole pass, including the burnout, I can give you some pointers.
Thanks
My question is at what rpm should one be launching at with such a setup. They hook very well when launching at about 3500rpm, I think they had 12-14psi in each tire. Should I increase at which point I launch at? Is 12-14 PSI to low of a tire pressure?
The launch rpm depends on the car and track conditions. Try to launch as high as you can without spinning. If anything lower the tire pressure. 12-14 is a pretty high pressure for a full slick. Try like 10, preferably lower.
Also in the pit, when I get in the water should I just do a quick little spin? Ie hold the handbrake rev the car till it spins out of the hole then give it to warm the tires up?
You want to roll through the water box and then stop when your front wheels are slightly past the box. Don't stop in the water, because once you start your burnout, water will sling up into the wheel wells and drip down on the tires when you are going to stage. I found the best way is to rip the ebrake and do a 2ND gear burnout. You will heat up the tires much more efficiently with a 2nd gear burnout. Hold for like 3-5 seconds and drop the ebrake and ride it out.
When I'm waiting for the light I was told to have the handbrake on and Rev the car up, that way I have a load on the car and not have the car shocked when I luanch (IE dumping the clutch). Is this correct?
Just having the ebrake on will not load up the car. In order to preload the car, you have to have the ebrake on and release the clutch to just about when it engages. This is hard on the clutch though. I always slip the clutch out quickly, never really do a complete dump.
Just trying to get a clear image of what needs to be done. I didn't have much time to play around last time I went.
Practice makes perfect. If you have someone take video of your whole pass, including the burnout, I can give you some pointers.
Thanks
Good luck man!
09-27-2010, 05:13 PM
#4
Ohh yes, I forgot to mention that I let the clutch out to a point where the car would want to go and then gave it a bit of gas when I was at the line. I'll take a couple of videos this weekend.
With the tire pressure at 12-14 psi the tires would slip but then gain traction in no time. I can play around with pressure. I think that's a good starting point (tire pressure) and i'll concentrate on the driving then when I feel I can do better lower the tire pressure and see what happens.
I'm aiming for 13.6, hope I can do it.
Thanks for the info!
With the tire pressure at 12-14 psi the tires would slip but then gain traction in no time. I can play around with pressure. I think that's a good starting point (tire pressure) and i'll concentrate on the driving then when I feel I can do better lower the tire pressure and see what happens.
I'm aiming for 13.6, hope I can do it.
Thanks for the info!
Last edited by OC_Nooby; 09-27-2010 at 05:16 PM.
09-27-2010, 05:14 PM
#5
Thanks!
Learned most of this just by going to the track. Learning from veterans is the way to go. Don't be afraid to ask people what to do at the track.
Sounds good. Definitely don't mind helping out a fellow maxima enthusiast.
Learned most of this just by going to the track. Learning from veterans is the way to go. Don't be afraid to ask people what to do at the track.
Sounds good. Definitely don't mind helping out a fellow maxima enthusiast.
09-28-2010, 12:02 PM
#6
I have found my times are best at around 11.5psi-12psi. I have tried lower pressure and not seen any ET improvement, but I did see my trap speeds start to go down.
Try the burnout in second gear if you can. Gets them hotter faster. I like to burn them down til I can smell tire smoke. A quick little spin is not sufficient in my opinion. I turn the wheel side to side to get the sidewalls to flex and get the whole tire surface hot. I'm not sure how long exactly it takes me but probably at least 5 seconds. Then after I complete my burnout I do another quick dry hop between the water box and the line to make sure they are gripping like they should.
Honestly I don't think you have to worry about preloading the car. I have never bothered to anyways.
3500 is not high enough. I made the same mistake when I first started using slicks (and then again when I first used them on my turbo car, thinking that I was more likely to break something or spin them with more power.) start at like 4500 and up the RPM 500rpm each run until you find the highest you can use. You may end up launching from almost redline if you have a strong clutch in the car. I launched from 5500 when I was turbod (never made any passes on really good slicks like you have though. I was on some crappy ET Streets when I was turbocharged which aren't as good as your M&Hs, otherwise I would have launched even higher). with my current 3.5 NA setup I launch basically from redline.
Don't sidestep the clutch though. Just let it out basically as fast as you can slip it.
Try the burnout in second gear if you can. Gets them hotter faster. I like to burn them down til I can smell tire smoke. A quick little spin is not sufficient in my opinion. I turn the wheel side to side to get the sidewalls to flex and get the whole tire surface hot. I'm not sure how long exactly it takes me but probably at least 5 seconds. Then after I complete my burnout I do another quick dry hop between the water box and the line to make sure they are gripping like they should.
Honestly I don't think you have to worry about preloading the car. I have never bothered to anyways.
3500 is not high enough. I made the same mistake when I first started using slicks (and then again when I first used them on my turbo car, thinking that I was more likely to break something or spin them with more power.) start at like 4500 and up the RPM 500rpm each run until you find the highest you can use. You may end up launching from almost redline if you have a strong clutch in the car. I launched from 5500 when I was turbod (never made any passes on really good slicks like you have though. I was on some crappy ET Streets when I was turbocharged which aren't as good as your M&Hs, otherwise I would have launched even higher). with my current 3.5 NA setup I launch basically from redline.
Don't sidestep the clutch though. Just let it out basically as fast as you can slip it.
09-28-2010, 04:22 PM
#7
I have found my times are best at around 11.5psi-12psi. I have tried lower pressure and not seen any ET improvement, but I did see my trap speeds start to go down.
Try the burnout in second gear if you can. Gets them hotter faster. I like to burn them down til I can smell tire smoke. A quick little spin is not sufficient in my opinion. I turn the wheel side to side to get the sidewalls to flex and get the whole tire surface hot. I'm not sure how long exactly it takes me but probably at least 5 seconds. Then after I complete my burnout I do another quick dry hop between the water box and the line to make sure they are gripping like they should.
Honestly I don't think you have to worry about preloading the car. I have never bothered to anyways.
3500 is not high enough. I made the same mistake when I first started using slicks (and then again when I first used them on my turbo car, thinking that I was more likely to break something or spin them with more power.) start at like 4500 and up the RPM 500rpm each run until you find the highest you can use. You may end up launching from almost redline if you have a strong clutch in the car. I launched from 5500 when I was turbod (never made any passes on really good slicks like you have though. I was on some crappy ET Streets when I was turbocharged which aren't as good as your M&Hs, otherwise I would have launched even higher). with my current 3.5 NA setup I launch basically from redline.
Don't sidestep the clutch though. Just let it out basically as fast as you can slip it.
Try the burnout in second gear if you can. Gets them hotter faster. I like to burn them down til I can smell tire smoke. A quick little spin is not sufficient in my opinion. I turn the wheel side to side to get the sidewalls to flex and get the whole tire surface hot. I'm not sure how long exactly it takes me but probably at least 5 seconds. Then after I complete my burnout I do another quick dry hop between the water box and the line to make sure they are gripping like they should.
Honestly I don't think you have to worry about preloading the car. I have never bothered to anyways.
3500 is not high enough. I made the same mistake when I first started using slicks (and then again when I first used them on my turbo car, thinking that I was more likely to break something or spin them with more power.) start at like 4500 and up the RPM 500rpm each run until you find the highest you can use. You may end up launching from almost redline if you have a strong clutch in the car. I launched from 5500 when I was turbod (never made any passes on really good slicks like you have though. I was on some crappy ET Streets when I was turbocharged which aren't as good as your M&Hs, otherwise I would have launched even higher). with my current 3.5 NA setup I launch basically from redline.
Don't sidestep the clutch though. Just let it out basically as fast as you can slip it.
Do you do the burnout in the box for 5 seconds or roll through then handbrake and a 5 second burnout. Also can you explain to me why its better to launch at a higher rpm? When I launched at 3500rpm it hooked pretty well, im comparing to my streets as thats all I can compare to, lol.
Thanks!
09-28-2010, 05:38 PM
#9
The track I go to you back into it. It has a small dip. I guess I'll go into the dip, do a small rip to get the tires wet. Inch forward and light them up. When I went first I launched at 3500 rpm without preloading the motor. My friend told me not to do this as it "shocks" the drivetrain. It kinda makes sense, but its also seems to be hard on the clutch. I guess you can never win when on the drag, something always gets abused ^_^
Thanks for the info Nealoc187 and krazy6. This saturday if it doesn't rain I should have some videos/pics up.
Thanks for the info Nealoc187 and krazy6. This saturday if it doesn't rain I should have some videos/pics up.
09-28-2010, 05:41 PM
#10
Also I used to launch at 45-5k on my dr's at 14psi and could hang with 6.0 gto's from a dig.
09-28-2010, 05:59 PM
#11
When I left the line I would hit about 5 PSI and the meth would kick in. It caused a blowout in the spark (gapped at 0.28). I got my coil booster put in and running the coils at 16v with a 0.36gap. I want to let the meth kick in at 5 psi. It does it in steps so I don't get the full blast at 5psi but it gradually will increase to full at 14psi. I may not need it to start till 8PSI, but I just want to be safe. Still playing with it.
09-28-2010, 06:00 PM
#12
I do 2nd gear burnouts and when I launch, I dump the clutch off the rev limiter. I run M&H 23x7.5x15 slicks @ 12psi. Don't worry about drivetrain shock. Slicks absorb alot of the shock.
09-28-2010, 06:08 PM
#13
09-28-2010, 06:41 PM
#14
When I left the line I would hit about 5 PSI and the meth would kick in. It caused a blowout in the spark (gapped at 0.28). I got my coil booster put in and running the coils at 16v with a 0.36gap. I want to let the meth kick in at 5 psi. It does it in steps so I don't get the full blast at 5psi but it gradually will increase to full at 14psi. I may not need it to start till 8PSI, but I just want to be safe. Still playing with it.
BTW, with slicks and the bog gone you should be running low 13's if not 12's but at the very least a new pb
good luck, when you hitting the track
IE brother and friend.
09-28-2010, 08:25 PM
#16
I'm planning on launching off the limiter this friday and saturday. Got some 26" ET streets to fit my car. Took some grinding to fit the 16" wheels. lol
This wheel/tire setup is soooo much lighter than the stock 18s.
I think low 13s would be possible with a badass 60ft. 13.5 should be easy to attain on your slicks.
09-30-2010, 02:55 PM
#20
Going to the track in 2 days, I'll update with videos and time slips. As long as it doesn't rain >_<
I did add My launch control to activate at 4500, ill keep bumping it up from there when at the track. I also have this damn exhaust leak that is being addressed on Friday. Before they claimed sunny on Saturday, now its cloudy. Lets hope it doesn't become rain. That would suck...
I did add My launch control to activate at 4500, ill keep bumping it up from there when at the track. I also have this damn exhaust leak that is being addressed on Friday. Before they claimed sunny on Saturday, now its cloudy. Lets hope it doesn't become rain. That would suck...
Last edited by OC_Nooby; 09-30-2010 at 03:44 PM.
10-02-2010, 02:33 PM
#22
EPIC fail today. It was around 11°C this morning. I couldn't hook with the slicks at all. Went from 14PSI to 11PSI on the slicks. Also the spark plug gap of 0.36 was to much. The car would start to stutter. My meth wasn't even kicking in so thats for sure a spark issue. I will regap to 0.30 - 0.32. Was going to keep running as I was getting better times until a guy asked whats under the hood. So i pop the hood show him the supercharger. I look at the belt on the sc pulley and noticed it has skipped a rib. That was Game Over right there. Also it was on/off rain. I assure you that didn't help the situation. I'm freaking pissed.
I have a video, and some pics of my car. I'll post them later.
Right now, I'm just going to wait for my dyno....I might hit a track in Montreal where they spray the track and actually have many cars running....
On a side note, the car hauled *** after the 60 foot. But i had huge issues on the 60 foot. Will post later tonight.
I have a video, and some pics of my car. I'll post them later.
Right now, I'm just going to wait for my dyno....I might hit a track in Montreal where they spray the track and actually have many cars running....
On a side note, the car hauled *** after the 60 foot. But i had huge issues on the 60 foot. Will post later tonight.
10-02-2010, 04:35 PM
#23
EPIC fail today. It was around 11°C this morning. I couldn't hook with the slicks at all. Went from 14PSI to 11PSI on the slicks. Also the spark plug gap of 0.36 was to much. The car would start to stutter. My meth wasn't even kicking in so thats for sure a spark issue. I will regap to 0.30 - 0.32. Was going to keep running as I was getting better times until a guy asked whats under the hood. So i pop the hood show him the supercharger. I look at the belt on the sc pulley and noticed it has skipped a rib. That was Game Over right there. Also it was on/off rain. I assure you that didn't help the situation. I'm freaking pissed.
I have a video, and some pics of my car. I'll post them later.
Right now, I'm just going to wait for my dyno....I might hit a track in Montreal where they spray the track and actually have many cars running....
On a side note, the car hauled *** after the 60 foot. But i had huge issues on the 60 foot. Will post later tonight.
I have a video, and some pics of my car. I'll post them later.
Right now, I'm just going to wait for my dyno....I might hit a track in Montreal where they spray the track and actually have many cars running....
On a side note, the car hauled *** after the 60 foot. But i had huge issues on the 60 foot. Will post later tonight.
Post the vid and I'll see if I can help you out.
10-03-2010, 10:34 AM
#24
Alright the video is a Lil crappy. You have to crank the audio to hear my car, you can see the smoke from the burnout. I did it in second gear. I then preloaded the car while on the 2 step lunch control at 4500rpm. You'll notice that its not going anywhere because I had to let go of the gas then stomp on it to stop the blow out. Out of the 7 runs I did I did not have 1 clean run.
Again temps 11°c,
on/off rain (enough to wet the ground),
not enough cars to keep the track warm,
Tires set to at 11PSI still did not hook,
spark blow out that for some reason only happens at the track,
Supercharger belt came of the pulley by a rib,
Ohh also had a fuel leak earlier on in the day, that was fun but fixed.
and last but not least Me....
So this is my car and the video.
http://www.youtube.com/watch?v=Fe0Tr-tqZ-8
Again temps 11°c,
on/off rain (enough to wet the ground),
not enough cars to keep the track warm,
Tires set to at 11PSI still did not hook,
spark blow out that for some reason only happens at the track,
Supercharger belt came of the pulley by a rib,
Ohh also had a fuel leak earlier on in the day, that was fun but fixed.
and last but not least Me....
So this is my car and the video.
http://www.youtube.com/watch?v=Fe0Tr-tqZ-8
10-03-2010, 02:52 PM
#26
Can't really tell much from that video. It just sounds like you need to figure out the spark issue.
Also, try slipping out the clutch fast. Try not to dump it, should help. Hard to explain. lol
This should help your 60' times.
I launch at 6500rpm and slip it out really fast. Got me a 1.8 60'
Had my tires at 12psi.
Also, try slipping out the clutch fast. Try not to dump it, should help. Hard to explain. lol
This should help your 60' times.
I launch at 6500rpm and slip it out really fast. Got me a 1.8 60'
Had my tires at 12psi.
10-03-2010, 03:26 PM
#27
Yah my friend didn't really want to film...
Basically at the launch:
Hold throttle (launch control activated at 4500rpm).
Lift the handbrake, while pressing in the button so it doesn't lock.
Release the clutch until I feel the car wanting to move.
When the tree goes to its last yellow I go.
I felt the car hook before at higher tire pressure, there was no hooking that day.
Basically at the launch:
Hold throttle (launch control activated at 4500rpm).
Lift the handbrake, while pressing in the button so it doesn't lock.
Release the clutch until I feel the car wanting to move.
When the tree goes to its last yellow I go.
I felt the car hook before at higher tire pressure, there was no hooking that day.
10-04-2010, 06:08 PM
#31
I did a 14.1 with a 2.2 60 foot @ 103MPH. I wasn't hooking. That was the best one.
Might go to Montreal this weekend, they spray the track, many cars go so its a warmer for sure.
Didn't have tools that day, just what I needed for the slicks to be swapped. If I go to the track in Montreal I'm definitely going to lower the gap, increase my rev limit to 7k. I'll go all out! Weather dependent that is.
Might go to Montreal this weekend, they spray the track, many cars go so its a warmer for sure.
Didn't have tools that day, just what I needed for the slicks to be swapped. If I go to the track in Montreal I'm definitely going to lower the gap, increase my rev limit to 7k. I'll go all out! Weather dependent that is.
10-04-2010, 08:55 PM
#33
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The "PB" video in my sig has a decent example of a quick slip launch from redline. That's with drag radials, you can be even more aggressive with slicks.
10-04-2010, 09:16 PM
#34
10-07-2010, 08:32 AM
#38
Don't know if I asked this but, how come I only blow spark in first gear? How come I don't blow spark in 3rd gear where there is a lot more air coming through?
Or is it because I have more fuel then air in first gear but as I reach 3rd gear I have more air coming and that helps with the additional fuel?
Does the car have a bigger spark in say 3rd gear as opposed to 1st gear?
Or is it because I have more fuel then air in first gear but as I reach 3rd gear I have more air coming and that helps with the additional fuel?
Does the car have a bigger spark in say 3rd gear as opposed to 1st gear?
10-08-2010, 05:53 PM
#39
are you positive it's spark blowout?
I suppose it could be happening in first gear because the capacitors in the coils need to charge and discharge much more quickly, maybe they aren't having time to charge fully. that means you have some other problem going on though, because that shouldn't be happening.
I suppose it could be happening in first gear because the capacitors in the coils need to charge and discharge much more quickly, maybe they aren't having time to charge fully. that means you have some other problem going on though, because that shouldn't be happening.
10-08-2010, 06:15 PM
#40
are you positive it's spark blowout?
I suppose it could be happening in first gear because the capacitors in the coils need to charge and discharge much more quickly, maybe they aren't having time to charge fully. that means you have some other problem going on though, because that shouldn't be happening.
I suppose it could be happening in first gear because the capacitors in the coils need to charge and discharge much more quickly, maybe they aren't having time to charge fully. that means you have some other problem going on though, because that shouldn't be happening.