mxzxracer16

Hey guys looking for some others readings for comparisons, on my cl65 which has a tune on it on hard pulls from down in the lowend my data logger "dashdaq" I see 37psi it maxs for a split second there and drops to about 35ish then slowly drops on the rest of the pull. Soooo....

-1st questions how much of a range do the MAP sensors have Ive never seen over 37 listed so im thinking thats the end of the range, and also because it feels to me is that once it hits the number "top of its range" that it kicks it into a bit a limp and starts pulling boost back thats why I think im seeing my intial drop as soon as it hits 37.

-2nd So a reading of 37 = 22.7 boost at the intake is anyone else getting this high of a reading?

Any other info from fellow v12tt owners would be greatly appricated. Thanks

drabux

My understanding is that stock boost for the 65 is 1.5 bar = 22 psi
Not sure what MAP sensor we have fitted. My guess would be 3 bar (2 bar at atmosphere) = 5 volts at 29 psi. Easy to test.

drabux

Just to add that it is your ECU map that will limit boost, not your MAP sensor. The latter can usually read quite a bit above what your ECU map will allow.

Benz-O-Rama

That's normal. 37MAP is roughly 22.3 boost psi. These cars have very small turbos, and spike up very quickly. From there, they start to run out of breath and boost tapers. There are impeller wheel and complete turbo upgrades available for these cars too.

Normal for the M275 V12TT.

drabux

Absolutely true. They have boost characteristics which typify a small turbo: early max boost followed by relatively swift decline to redline. My remapped S600 shows a peak of about 21psi dropping to below 13 psi by 5000 rpm. At high revs the teeny turbos simply can't supply the required volume for high boost and if the wastegates were kept closed would produce a lot of heat for not much more boost.

I wouldn't knock such characteristics, though. I've owned big turbo cars which are not nice to drive, feeling slower in everyday driving than if they'd had the little stock turbos.

Benz-O-Rama

Yes, exactly.

I'm sure it was done to decrease turbo lag. In stock form, the M275 is almost devoid of any lag. Once you get an ECU tune though, like many of us, lag is slightly present.

mxzxracer16

Do you know of who has a kit available for bigger turbos? I know Speedriven is working on a larger turbo kit now and has impellers, but are there any bigger turbo set ups available beside the black series turbos, which arent that much bigger the the 65 anyways?!?

Benz-O-Rama

Speedriven is going to be your only source right now that I know of. The problem with upgrading the turbos on these cars, is not the turbos themselves, but rather the exhaust manifolds. As you probably already know, the turbo housings are a 1pc cast with the manifolds. You cannot just simply swap the turbos. So if you do, you must also have a set of custom headers made, and there's just nobody doing that right now, except for Speedriven.

mxzxracer16

Yeah ive been waiting to hear from Marcin on if the kits a success and ready to ship Ill be waiting and ready to order!! I would love to have 21-22 psi all threw the RPMS

Benz-O-Rama

I think it's the same package that V12Goodspeed used on his E55, that he converted into an EV12.


https://mbworld.org/forums/w211-amg/373559-ev12.html

Speedriven1

Well got a little info for you guys. The 600 turbos with the billet upgrade will flow about 20-22psi to redline. The 65 turbos with billet upgrade will make a little more. As for the big turbo kit, car is running. Has been for about a week now. Been working on software for both ecu and tcu. Once we got up to about 18psi on the new manifold/turbos, I can't get the trans to stay in gear. BTW, we're getting about 3psi at 2000rpm with the new setup so lag is deffinetly not an issue.
As soon as I get the trans to play nice we'll load some vids up.

Stay tuned....



Marcin

freestylebiker3

my 2005 cl65 will not boost more then 14-15 psi and i have a ecu and tcu tune installed.. factory max boost is around 22psi i wonder how my tuned cl65 only reaches high of 15psi

drabux

Two most likely possibilities I can think of:

1. Check your pump is working.
2. Check that it has been bled properly.

Details of how to check both can be found on this forum.

Alanb

freestylebiker3

the pump has been bled and check by the dealer 2 weeks ago whille they were changing my cat converter

drabux

Okay. Have you connected up a obd reader to see what is being logged? Any anomalies (esp air inlet temp)?

freestylebiker3

i have hooked up the star computer and looked at the live date and noticed turbo temps and heat exchanger temps were high.. the dealers bled the heat exchanger and check if the pump was bad.. since that day i have not hooked up the computer to check for temps.... also i have had the mysterious misfire on my car that no dealer and can fix.. i have spent $5000 dollars replacing all the known parts and misfire still does not go away.. i wounder if the misfire is causing my low boost pressure

drabux

I take it that the $5000 included buying new coil packs and new plugs? Low boost wouldn't cause a misfire BUT high inlet temps post heat exchanger can. I had misfires prior to replacing my pump and I know that others have had misfires that were eventually traced to high inlet temps.

I would strongly suggest checking temps again by buying a cheap OBD reader and tracking temps while driving. You can buy cheap Chinese ones on ebay which can bluetooth to your phone.

Alanb

freestylebiker3

i will hook up a scanner to check the temps again... for my boost problem, when i was thinking is maybe since i have a misfire, the computer can be limiting the boost output to protect the engine becuase of the misfire

i changed both coil rails, coil driver,spark plugs and gapped the plugs, air filter, fuel filter, i changed my passenger side cat converter becuase misfire is on passenger side bank, bled heat exchanger from dealer, changed o2 sensors, cleaned carbon on throttle body,fixed any bad vacume lines that i can see...

so at this point i will check my temps, i have a clicking noise coming from my throttle body and it might be a problem, also maybe the dealer sold me a defective passenger side coil rail who knows...

FYI: the dealer did $22,000 of repairs and mantiance work last year on my car

stockC43

When does your car misfire? It has been known that on hot days if your car is hot when you shut it off and restart soon after (within 15 min) the fuel can boil in the rails causing a random mis on start up. I have also seen a hand full of bad injectors. While rare, it can happen. Wich cylinders are misfiring? Coils are usally in groups of 3 or 6 on a single bank. Ex 789. Not random and not a single cyl usally.

freestylebiker3

my car misfires in the morning when it is cold.. and only after the air injection shuts off.. so about 20 sec after first start up in the morning and the misfire will go away when i drive it and heats up, but after it heats up the misfire is so small that you can only notice it with the mercedes computer, with there live data view on misfires.. for my coils it is random, cyl 1,5,3,2 will misfire

stockC43

Cyl 1,2,3 looks like it could be a coil and 5 pops up due to 1,2 and 3. Hard to say though. When your coils were replaced were they new MB ones or used/rebult? Some times extended warranty companys send thier own parts wich can be questionable. M137 and m275 coils look the same however the part number is diffrent. If they send there own parts they could be mixed up. If that's not it I don't have a clue without seeing it. If you get into boost does it kill boost and shut down bank 1?

freestylebiker3

part number is correct, and also the coil was replaced at the dealer ( customer pay ) it might be a bad coil from the dealer

Dynodaddy

I have precision turbo billet compressor wheels in my S600 and it will hold 20psi until the rev limiter. The issue with these cars is not the turbo's it is the tiny exhaust manifolds that are creating an insane amount of backpressure.
I started from scratch and just finished the first tuning session with Jerry @ Eurocharged this weekend @ Autoscope in Dallas. I have a bad coilpack and we didn't get too far with the tuning but @ 17psi the car made 808rwhp and 1327ftlbs of torque on 93 octane only pulling to 4600rpm's. I will push the car as far as the injectors will allow during the next dyno session, and I have a feeling we will not need race fuel to max the injectors out. I believe I will make 900+ rwhp and almost 1500ft lbs of torque if the dyno can hold the power.
This car has the power to easily accomplish my goal of running 9 second 1/4 mile times and with any luck will perhaps break the 9.5 second barrier.

Malones Perf.

That is crazy power that your putting down. What turbo's do you have on the CL and who did all the work looks fantastic nothing looks out of place. Can't wait to here more I dropped the motor out of my car a few months back but scraped the project of fabing up manifolds and turbos. I would like to hear more about your results!

Dynodaddy

I did 95% of the work including all TIG welding and my brother did the other 5%. I am running a pair of Precision 58mm turbo's.