Slowest MSM build thread evar! Now a whole lot less slow.
#103
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So got bunch of miles on the new twin disks and they seem to be holding. I have always loved shitty hard to modulate clutches that all my friends hate but this is a new level in a street car....wow. Its grab point is a few millimetres and its on or off. I only hope that the 5lb flywheel is whats keeping my 6 speed alive cuz the thing a beast. Its holding tho!
The car is amazing. I have a 730whp Foxbody and I feel this pulls just as hard (when it hooks). Its so unsuspecting and that has surprised a few (C5 with bolt ons, Few Hemi chargers and challengers, S550 stangs, Built A4, and a 750 bike on the hwy). Got a little more tuning to make the idle correct but the combination of power and handling is unmatched. Thanks everyone for the years of answering stupid questions.
The car is amazing. I have a 730whp Foxbody and I feel this pulls just as hard (when it hooks). Its so unsuspecting and that has surprised a few (C5 with bolt ons, Few Hemi chargers and challengers, S550 stangs, Built A4, and a 750 bike on the hwy). Got a little more tuning to make the idle correct but the combination of power and handling is unmatched. Thanks everyone for the years of answering stupid questions.
#105
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So after almost 2,000 hard miles at 20+ psi I pulled the plugs to change them and see how things are doing and to my surprise, they look way better than I had expected. Good job on the tune 18PSI!
BMW Trans coming soon!
BMW Trans coming soon!
#106
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So its been on road all summer and I have been contending with violent wheel hopping issues and traction issues and as the temps came down the power went up and the traction got worse. Went from a 205 660 tire to a 225 AR1 to a 245 AR1 and now to a 225/50/15 ET street. Traction with the ET has got much better. This has never been built to be a drag car but it was plan scary in 1st 2nd and 3rd with tire spinning. Car definitely hurt some feelings on the streets, most dont see it coming as the car looks basically stock other than hood vents. Now with some traction I'm sure I will be finding the next weakest drivetrain link. Any bets? MSM 6-speed or the MSM rear (braces welded on)? I have a BMW 5-speed in garage waiting for the trans to go but it has not yet.... If that pops I'll prob swap trans in and see how long rear lasts, still dont own that replacement yet. Getrag or 8.8? Hmmmm
Picked up a Draggy as that seems to be the go to for testing, here my best 0-60 time in 45* weather on a unprepped street with tires hopping. I'm happy to be in the 3s. I still have to bump up the RPM so I can get to 60 with out a 3rd gear shift, hitting rev limiter right at end. Bet mid 3s are possible...here tesla tesla
Picked up a Draggy as that seems to be the go to for testing, here my best 0-60 time in 45* weather on a unprepped street with tires hopping. I'm happy to be in the 3s. I still have to bump up the RPM so I can get to 60 with out a 3rd gear shift, hitting rev limiter right at end. Bet mid 3s are possible...here tesla tesla
#108
So its been on road all summer and I have been contending with violent wheel hopping issues and traction issues and as the temps came down the power went up and the traction got worse. Went from a 205 660 tire to a 225 AR1 to a 245 AR1 and now to a 225/50/15 ET street. Traction with the ET has got much better. This has never been built to be a drag car but it was plan scary in 1st 2nd and 3rd with tire spinning. Car definitely hurt some feelings on the streets, most dont see it coming as the car looks basically stock other than hood vents. Now with some traction I'm sure I will be finding the next weakest drivetrain link. Any bets? MSM 6-speed or the MSM rear (braces welded on)? I have a BMW 5-speed in garage waiting for the trans to go but it has not yet.... If that pops I'll prob swap trans in and see how long rear lasts, still dont own that replacement yet. Getrag or 8.8? Hmmmm
Picked up a Draggy as that seems to be the go to for testing, here my best 0-60 time in 45* weather on a unprepped street with tires hopping. I'm happy to be in the 3s. I still have to bump up the RPM so I can get to 60 with out a 3rd gear shift, hitting rev limiter right at end. Bet mid 3s are possible...here tesla tesla
Picked up a Draggy as that seems to be the go to for testing, here my best 0-60 time in 45* weather on a unprepped street with tires hopping. I'm happy to be in the 3s. I still have to bump up the RPM so I can get to 60 with out a 3rd gear shift, hitting rev limiter right at end. Bet mid 3s are possible...here tesla tesla
#110
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So car sat for August (100*+ here) and now cooler temps have come back and I have been driving it again and it has developed a high RPM miss. Changed plugs and the old ones gaped at 35 looked great but I replaced them and gaped down to 25 and same issue. Could an LS coil be failing?
#111
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Holy **** *****, you're concerned with the misfire, not running at 12.5 at 240kpa? Also your batt voltage goes to 12.6 at 6000rpm. Might look into that too.
Also, MSM should have VSS at the ECU. Calibrate it, set your gear, and then logs are more useful. Said 12.5 log is possibly due to lower gears ripping through the fuel table quickly, but I can't tell without gear/VSS reference.
Edit: Looking again, you're running 17-18 degrees at peak torque, seems a bit advanced for my liking, the whole table just doesn't decrease with boost very much. I usually decrease 1 degree per psi of boost, or 2 degrees every 14kpa. This has to taper off eventually, but using that math, your timing at 26psi, which is where your table ends at, would be at 4 degrees. I'm not saying run that, but maybe close to 10, I realize you're only running about 20 psi, but if anything happens and you overboost, your timing isn't going to drop almost at all.
Also, MSM should have VSS at the ECU. Calibrate it, set your gear, and then logs are more useful. Said 12.5 log is possibly due to lower gears ripping through the fuel table quickly, but I can't tell without gear/VSS reference.
Edit: Looking again, you're running 17-18 degrees at peak torque, seems a bit advanced for my liking, the whole table just doesn't decrease with boost very much. I usually decrease 1 degree per psi of boost, or 2 degrees every 14kpa. This has to taper off eventually, but using that math, your timing at 26psi, which is where your table ends at, would be at 4 degrees. I'm not saying run that, but maybe close to 10, I realize you're only running about 20 psi, but if anything happens and you overboost, your timing isn't going to drop almost at all.
#112
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Holy **** *****, you're concerned with the misfire, not running at 12.5 at 240kpa? Also your batt voltage goes to 12.6 at 6000rpm. Might look into that too.
Also, MSM should have VSS at the ECU. Calibrate it, set your gear, and then logs are more useful. Said 12.5 log is possibly due to lower gears ripping through the fuel table quickly, but I can't tell without gear/VSS reference.
Also, MSM should have VSS at the ECU. Calibrate it, set your gear, and then logs are more useful. Said 12.5 log is possibly due to lower gears ripping through the fuel table quickly, but I can't tell without gear/VSS reference.
12.6 does not sound bad but could it be low enough to effect coil firing?
#113
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Anything in the 12s at 18psi is going to be bad for the long term health of your pistons. The bigger problem is your alternator. That'll go up and down the dead time table, wrecking havoc on all Vlad's hard work. Fix that first (belt slip maybe?), then do another log in 5th from a low RPM to redline.
#115
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Anything in the 12s at 18psi is going to be bad for the long term health of your pistons. The bigger problem is your alternator. That'll go up and down the dead time table, wrecking havoc on all Vlad's hard work. Fix that first (belt slip maybe?), then do another log in 5th from a low RPM to redline.
Belt slip.....I'll check it today.
When we were street tuning it I gave up at 15psi in 3rd gear pulls and went to dyno after almost hitting a racoon at 80mph.
#118
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If your voltage is 12.5 instead of 14, all your voltage compensations for injectors, idle valve, etc change. Most people don’t do a lot of tuning at 12.5 volts, so I wouldn’t expect it to be perfect. Your fuel pump is also stressed enough at those demands, and then whatever problem you’re having is also giving it 10% less voltage, so your fuel pressure might be dropping too. This is why I like a fuel pressure sensor, and properly set up compensation. As FP drops, the ecu should compensate with more DC.
#119
Got your logs, will check them out when I get a chance. The AFR was nowhere near 12.5 when we tuned so stay out of boost until we figure out the culprit. I agree with Curly, either dying fuel pump or voltage drop could be it, among other reasons.
*EDIT: reviewed logs. I stand by the above. Nothing else stands out to me. Let's get a fresh pump in there since you already have one and was planning to drop it in anyway.
1,000% agree with this. TRUTH
*EDIT: reviewed logs. I stand by the above. Nothing else stands out to me. Let's get a fresh pump in there since you already have one and was planning to drop it in anyway.
Your fuel pump is also stressed enough at those demands, and then whatever problem you’re having is also giving it 10% less voltage, so your fuel pressure might be dropping too. This is why I like a fuel pressure sensor, and properly set up compensation. As FP drops, the ecu should compensate with more DC.
Last edited by 18psi; 10-13-2023 at 01:10 PM.
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