My SL55 1/4 run after ECU tune. What's wrong?

[cdsjklee]

I need some feed back about my SL55. Yesterday I took SL to the local race track (Sacramanto race track) to do 1/4 mile Run. I was bit disappointed about the result. Is it something wrong with my run or the car. My SL is not any faster than before I did the tune. I did the 1/4 run few times before I did ECU Tune and I had almost same result It usually ran at high 12's but yeaterday I ran 2 high 12's and rest are 13's. Please give me some info or feed back I did not see any gain in time after the tune. local temp was 60 F. I was running on HRE 20" with PS2 this is what the reaults are ---------Reaction---I1----I2------I3------M.P.H(I3)---I4-------E.T-------M.P.H 1st run--.287---2.349--5.637---8.449---87.997---10.859---12.868---114.326 2nd------.622------------5.722---8.523---88.715---10.922---12.916---114.874 3rd-------.867---2.143--5.898---8.774---87.136---11.212---13.236---113.226 - 4th ------.398-----------6.052---8.922---86.930---11.359---13.381---113.725 I was expecting better time but this is what I got. What do you think about this run with ECU tune. Right after I did the TUNE My SL felt it did gain some power but this is the result after the Run. My run times are almost same as before the TUNE. Any one has info.of the 1/4 mile time of stock SL55? Thanks

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[Benz-O-Rama]

Forget about ET, there's too many variables involved that can inflate that number. What you should be focusing on is trap speed. Looks like you're trapping a little bit more than what a stock SL55 traps. Sunir's ecu tune only, trapped 113-115, IIRC. And his car ran as low as 12.0x

2 questions:

1. What were your pre-tune trap speeds
2. Who did your tune?

[cdsjklee]

I have Jerry"s TUNE (EUROCHARGED) after the Tune I really thought My SL55 gained some power so I expected better run times.
I used to run with MY stock 18" wheels with Michelin sports all season tires.
Yesterday I ran with HRE 845R 20" with Michelin PS2. I usually use my stock wheel at the Track but I did not have time to change the wheel so I ran with it.
before I really did not think too much about the Trap speed I was more on the times
My trap speed before tune with stock set up was High 112.XXX to Mid 113.XXX.
So couple runs I did at my usual time with higher trap speed. But after 2nd run I could not go over Mid 113.XXX M.P.H. I had total of 8 runs only first 2 runs pass the trap speed of 114.xxx M.P.H 2nd run with 114.874 which is really good .But after that I could not get any better than 5th run. On the street I could not feel if it has lost the power It runs well.

[jmf003]

+1 to Benz-O's comments about trap speed.

You picked up 1-2 mph while also going from 18" to 20" wheels. (Larger/heavier wheels can reduce trap speed). That's a good improvement! No reason to feel bad about those results.

Heat soak may have been limiting you on your later runs. Some guys ice down their intercoolers between runs to help with that issue.

[Benz-O-Rama]

Looks like you picked up the same gains at Sunir's Eurocharged shelf tune. As jmf003 stated, you went to 20" wheels and still picked up mph in the 1/4. Your car has definitely picked up HP. Sunir's car was running 12.0x with the same mph as you. Your car will do the same with proper driving. Ice down your blower between run. The 55K cars suffer from heat soak very easily.

[cdsjklee]

Temp of the car was normal driving temp even after 4th run there were break between runs 20 min, to almost an hour break. The temp it was very cool around 55F to 60F at the Track. After the 2 run I could not get any better than 113.10 M.P.H with 13.3xx sec. Temp gauge was just a little over half way mark so car was not hot at all. Do I still have to ice down the super charger?

Maybe I should take SL to Track next week again with few bags of Ice.
Any tips to improve the time.

[Benz-O-Rama]

Originally Posted by cdsjklee

Temp of the car was normal driving temp even after 4th run there were break between runs 20 min, to almost an hour break. The temp it was very cool around 55F to 60F at the Track. After the 2 run I could not get any better than 113.10 M.P.H with 13.3xx sec. Temp gauge was just a little over half way mark so car was not hot at all. Do I still have to ice down the super charger?

Maybe I should take SL to Track next week again with few bags of Ice.
Any tips to improve the time.

Temp guage shows coolant temp. Heat soak is associated with Intake Air Temp or IATs. One has nothing to do with the other. 20 mins is no where near enough time to cool one of these down. Actually, the car probably got hotter in those 20 minutes. The S/C and intercooler if possible should be iced for an hour between runs for optimal results.

It certainly seems the gains are there. There is a great 'How to drag race' sticky in the W211/AMG forum. Take a look, there's good tips in there for new racers like yourself.

[cdsjklee]

Thanks for the info. Yes I am kind of new at 1/4 mile run. I only did this 4 times with this SL. I do go to Thunder Hill race track few times a year with my M3 so 1/4 mile run is not my regular track event.
I am taking SL to thunder hill tomorrow. I will put my stock wheel on for the tomorrow's event and take the SL back to 1/4 run next week.

[Benz-O-Rama]

Originally Posted by cdsjklee

Thanks for the info. Yes I am kind of new at 1/4 mile run. I only did this 4 times with this SL. I do go to Thunder Hill race track few times a year with my M3 so 1/4 mile run is not my regular track event.
I am taking SL to thunder hill tomorrow. I will put my stock wheel on for the tomorrow's event and take the SL back to 1/4 run next week.

Atta boy

Again, keep hood open between runs and ice that bad boy down. Stick to the hints and tricks in that W211 AMG sticky thread and practice, practice, practice. I know it's hard, but when trying to prove HP gains, try not to focus on the ET, but rather the trap speed.

[cdsjklee]

Thanks BENZ-O-RAMA. for the tip. I guess I have a new hobby now I will
learn to launch the car properly.

Went to Thundere hill today. Could not take the SL to Track instead I took My M3. Driving SL early this Morning. I heard some kind of Clunking sound coming from Passenger side rear wheel did not want to take the risk so SL stayed home.
Need to take the SL to the shop to check it out.

It was beautiful day had a blast at the Track.

[jmf003]

Originally Posted by Benz-O-Rama

Temp guage shows coolant temp. Heat soak is associated with Intake Air Temp or IATs. One has nothing to do with the other....

+1

Per PTE, the regular MB thermostat tries to keep the coolant temp around 210F and his modified t-stat around 180F. (pte thermostat)

If the IAT on our 55K engines gets above 140F the ECU starts to reduce power.

[bassn_07]

cdsjklee, Sacramento is also my home court and I would love to meet you at the track next week. If you like pm me your info and we could talk later in the week.

Your trap speeds look to be right on par with others on http://www.dragtimes.com/Mercedes-Be...ag-Racing.html. The last time we had a MB meet at Sacramento a LET tuned E55 (otherwise stock) was trapping right around 116, maybe plus or minus a bit. The E's are a tad lighter so the higher trap is probably due to less weight. I also noticed that your 60' time were pretty high and usually if you better that (clean run) both your traps and ET's would drop. Either way your car did fine but you just need a bit more practice launching.

I'm always looking for other MB members here in the bay area to meet up with. If you ever get the itch and want to meet up just shoot me a pm. Good luck and I hope to see ya at the track.

[FLSL55]

Get a pulley. You need a pulley AND a tune or it's not worth it. IMHO.

[Sunir]

Your trap speeds are right on...I was trapping 114's for most of the runs, with myself or BOR the trap was around the same, lowest of 113, most in 114, and highs in 115 mph.

Bassn_07, jmf003, and BOR are dead on with their advice and they are experienced drag racers...this 1/4 mile deal really is won or lost at the 60' - that it the most critical stat you can have and as that comes down...everything gets better...for example BOR was consistant 12.0x in my car and I was 12.3's to 12.4's ...comparing our traps were similar but he was 1.7 vs. my 2.0+ 60' times...

your car with just a tune is making the power it should if trap mph is an indicator (compared to my traps). I can't compare mine to before and after my stage 1 shelf ecu upgrade (tune is more a dyno thing, this was a handheld flash from Tony at the track) because never ran down the drag strip before and never got it dynoed, even now don't know what it makes...you do have to ice down the blower, this part sucks cause it takes time away from running and I like going continously back to back runs...I used 19's w/ regular toyo street tires...your wheel/tire choice can make a difference...i'm interested in some DR's for that reason down the road...

[Exotic-metal55]

Originally Posted by bassn_07

cdsjklee, I also noticed that your 60' time were pretty high and usually if you better that (clean run) both your traps and ET's would drop. Either way your car did fine but you just need a bit more practice launching.
.

You mean the ET would drop but TRAPS will go up, not drop!

CKSjdlee, can you post or transpose your best ET/60/trap before tune? It seems the added power has you spiining like crazy! I am alos ahving the same problem right now.. The spin kills the ET and trap on our cars.. Enough spin and your traction control will over-ride the off position and cause all your numbers to drop.. Weather also has to be in the same jenre..

A rough estimate, would be that you could pick up another 1.5-2 mph-ish by getting a 1.85ish sixty vs the spinning times you posted above..

[cdsjklee]

I am not really into doing 1/4 mile run . Before I just ran to see how fast SL55 is. So I only remember what my E/T was when it was bone stock. It ran at mid to high 12 sec. Well I am getting lot of info from you guys I will learn to do it right or at least try to do it right.
After the TUNE when I was at the track I tried not to slamming down the pedal when I launch. I just press the pedal not slamming. Maybe that was the reason my times are so high.

only MOD I have is Jerry's Eurocharged Tune, K&N drop in filters, Brabus exhaust and HRE 845R 20"wheels(these wheels are lighter than stock wheels)


Bassan 07 drop me a note if you guys are going to Track in the future I will gladly meet you guys and learn few tips. I was going to Sacramento race way this Wed. evening.

[bassn_07]

Originally Posted by Exotic-metal55

You mean the ET would drop but TRAPS will go up, not drop!

I meant drop because with my car a lot of my higher traps came off of crappy 60' times. I guess the best thing to do is concentrate on getting the cleanest run you possibly could. Maybe other members could jump in and give their thoughts on this topic. I'm curious if others also witness the same thing I do.

[Exotic-metal55]

Originally Posted by cdsjklee

I am not really into doing 1/4 mile run . Before I just ran to see how fast SL55 is. So I only remember what my E/T was when it was bone stock. It ran at mid to high 12 sec. Well I am getting lot of info from you guys I will learn to do it right or at least try to do it right.
After the TUNE when I was at the track I tried not to slamming down the pedal when I launch. I just press the pedal not slamming. Maybe that was the reason my times are so high.

only MOD I have is Jerry's Eurocharged Tune, K&N drop in filters, Brabus exhaust and HRE 845R 20"wheels(these wheels are lighter than stock wheels)


Bassan 07 drop me a note if you guys are going to Track in the future I will gladly meet you guys and learn few tips. I was going to Sacramento race way this Wed. evening.

If you get some of the local track racers to help you set your car up and launch, you will be happy. 20`s are lighter but have a thin tire side-wall and that can hurt traction.

Raise your ABC to the highest level, to help the launch. Lower tire pressure to 26psi ish and heat the tires up (smoke em) . Raise idle to 900-1000 rpm to just load drive train and then hit the pedal hard..If your track is prepped well, you will have full traction, even on 20`s.. Again, this just puts you in the range and it is best to get help on the line from a local racer..

[bassn_07]

Originally Posted by cdsjklee

Bassan 07 drop me a note if you guys are going to Track in the future I will gladly meet you guys and learn few tips. I was going to Sacramento race way this Wed. evening.

Avoid Wednesday night drags at all cost. I've only been there once and it is overly crowded with some of the worse track prep you'll ever witness. It cost only $10 or $15 dollars to run and it draws them all in. I believe they don't spray any VHT through the night. Stick with TNT days because this will be your best chance at getting to learn your car. I'll be there this Saturday with a few friends and you're more than welcome to join us...if they don't flake.

[RenntechE55]

Hey I think one of the big problems is the 20" wheels. Back when my car was a Stage I RENNtech I went to the track and got a best of 12.1 and went back with 20" wheels and my best was a 12.8. Both rims had the same tires on them but just the bigger mass makes a bigger difference. Also I found out the other night that a little bit longer brake stand helps on the 60ft time I was sticking to about three or four second burn outs and I was getting consistant 2 second 60ft times then I did about a 6 second burn out and got a 1.88ft time. Not sure if its the case with all street tires but it helped me.

[Benz-O-Rama]

Originally Posted by Exotic-metal55

You mean the ET would drop but TRAPS will go up, not drop!

Actually, bassn_07 is right. It's very common for traps to increase with worse 60's, due to spin. And conversely, you can see traps decrease when you dead hook.

[Exotic-metal55]

Originally Posted by Benz-O-Rama

Actually, bassn_07 is right. It's very common for traps to increase with worse 60's, due to spin. And conversely, you can see traps decrease when you dead hook.

It is far more common for traps to be higher with a great launch and no spin. That is the goal The high spin take off can increase traps in many cars but seems to be rare on our cars, as traction control will take over and then that kills the spin theory.. That may apply , if you run in dyno mode but that is not advised..

[Benz-O-Rama]

Originally Posted by Exotic-metal55

It is far more common for traps to be higher with a great launch and no spin. That is the goal The high spin take off can increase traps in many cars but seems to be rare on our cars, as traction control will take over and then that kills the spin theory.. That may apply , if you run in dyno mode but that is not advised..

Yeah, we're kinda saying the same thing, just differently. That why I stated "due to spin" in my post. There is no doubt, that 60's that have a lot of spin, without the interference of ESP, will net you higher traps, and worse ETs.

I'm speaking in generalities, you're speaking about MBs running ESP. And dyno mode is highly advised if you're gonna run a set of nice sticky drag radials.

But no way, with street tires if your car has any kind of torque. I could run in dyno mode on my E500 with street tires and not really worry about excessive spin on the sticky launch pad of MIR.