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trying to finger out why im down on power after SC pulley issue.
so make a long story short i had a spring crack on my 83mm pulley, at the time i couldnt figure out what was going on and drove the car for around 30-40 miles trying to trouble shoot the problem monitoring IAT temps, etc.
IAT were normal, so started to check around the engine bay when i realized how hot stuff was around the pulley area.
So low and behold the spring cracked but thank go got lodged and didnt weed whack the area, but it did cause that broken side to be in constant contact with the electromagnet/clutch which was hot to the touch.
pulled the pulley, sent it out for "service" received my pulley back with new rivets, clutch springs, and bearing as the heat fried the old one.
So now its reinstalled added a scattershield, gap is around .40mm, but the car feels sluggish.
i had around 10k on the pulley, and before the pulley failing, car was a beast, great power down low and on top, and was consistent. ever since i reinstalled the pulley the car has been bla. Car felt better in the 70* days then it does now when temps are low 50s to 60s. my buddy who has driven the car and with me all the time says it seems sluggish compared to before as well.
before the car would pull harder down low at around 2500rpms all the way to redline, now if i floor it at around 3500 in 3rd on the highway it feels bla.
so with that said any thoughts on what to check next? IC pump is good, charger does come on, dont see any dust residue from clutch, so i dont think its slipping but who knows. bummed my car is slower now with perfect boosting weather than it was end of summer.
Last edited by 06cls55amg; 10-19-2016 at 11:43 AM.
You can get boost readings from the OBDII port. Get something like the Innovate Motorsports OT2 or similar that will let you see boost and IAT as you're driving.
I had a similar problem where I was loosing boost. I thought it was the SC pulley clutch slipping but it turned out to be a loose hose on the surge tank. At any rate, log your boost, timing, and IATs so you know what you're dealing with.
hey guys , so been messing around with bafx bluetooth obd2 adapter and torque pro trying to figure out where my power went.
did a bunch of pulls and am noticing im only getting 6-8 lbs of boost from 3k rpm to the closer i get to redline it climbs a little. Sometimes in higher rpm say 4k ill see 12lbs, highest ive seen recorded on torque was 13.?.
tried to tell torque what to data log but for some reason when i email the file to myself it just shows longitude latitude.
my understanding is that i should have full boost as soon as the charger engages am i correct?
i dont see any belt or SC clutch residue anywhere... freakin stumped.
is it possible that the new springs they installed are not letting the pulley to engage 100%
Here's a graph of my boost (grey line) and IAT (pink line) during a 1/4 mile run earlier this year. I was using a clutched 77mm pulley, 82mm TB, Long Tube headers, and stock crank pulley at the time.
You can see my boost peaks pretty early in each gear, and tends to taper off until the next gear. It sounds like yours is doing the opposite?
You can get boost readings from the OBDII port. Get something like the Innovate Motorsports OT2 or similar that will let you see boost and IAT as you're driving.
I had a similar problem where I was loosing boost. I thought it was the SC pulley clutch slipping but it turned out to be a loose hose on the surge tank. At any rate, log your boost, timing, and IATs so you know what you're dealing with.
Joe, any chance you could take a pic and post of where the hose runs to on the surge tank?
My data logger is showing my max boost is 11.67. The pulley boost calculators say it should be between 14-15.
yes, im only seeing single digit boost numbers in 3rd gear starting at around 3k,
in 2nd gear around 3k the boost seems to be around 10-11 and climbs to 13lbs around 4000 -4500k
call me crazy, but before my pulley issue it felt like i had full boost at around 2500 rpm, everytime i slowly got into the 2500 rpm range it would surge or feel like the pulley was engaging. the car just feels worlds apart from what it was before, legit had more power in the summer then i do now in the fall. is it possible that these new springs are tighter and not worn in like old pulley was and is causing sluggish engagement?
even between 3 and 4 redline shifts or low 3krpm pulls it doesnt feel like that violent torque.power is their.... car is really bumming me out.
attached my iat, boost rpm graph. not sure why its so all over
Last edited by 06cls55amg; 11-04-2016 at 10:43 AM.
I really don't know what to make of that graph. Seems really noisy.
Mine had a loose clamp on one of the hoses that connect the output of the I/C to the input of the surge tank. Take your airboxes and Y-pipe off and look down the back of the motor under the throttle body. You will see two rubber hoses, each about 2.5" long and about 2.5" diameter. There are a total of 4 hose clamps. Reach down there and feel if the clamps are loose at all.
ya that was like 20 minutes of driving..... ill have to have my buddy log pull by pul next time.
i checked everything, all is well. like i said only thing that has changed is that upd installed 3 new springs that are notorious for weed wacking you car if you dont have a scatter shield. i drove the car with a broken spring for around 30 miles trying to figure out if it was my IC pump, a fluke, etc. the pulley got hot to the point that it caused the bearing to fail due to the pulley rubbing against the electro magnet where the spring let go.
car just doesnt seem to build boost like it did before in lower rpms, and the power is inconsistent. ive seen it pull single digit boost on certain 3k rpm pulls, and once in a while it 10 11lbs torque recorded 13.? for max boost even though i didnt see it. IAT temps never exceeded 104 , i always tried to to pulls when i was around 80-90*
You could rule out the new springs by installing your stock pulley if you still have it.
Have you replaced the SC coupling? (the electromagnet part of the clutch) Maybe that has been weakened by the damaged spring and is allowing the clutch to slip. Do you have a fixed pulley you can try? That would rule out the clutch altogether.
If there is a leak in your surge tank/intercooler/metal tube to supercharger (bottom driver side of blower) that would be significant enough to lose power........there should be some of the following symptoms noticeable:
1)surging or high idle 2)idle fault codes 3) pressure release noise from engine 4)rough idle
(I have 6 feet of extra intercooler piping on my car. Trust me, I have lived this issue on and off while developing my system.)
Boost seems low. How bad does the vehicle jerk when supercharger pulley engages @2500-3000 rpms? Try a gradual acceleration in 2nd gear and let the supercharger engage. I question because if the pulley is engaging properly.....you will feel it.
14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
Originally Posted by JoeJErnst
You could rule out the new springs by installing your stock pulley if you still have it.
Have you replaced the SC coupling? (the electromagnet part of the clutch) Maybe that has been weakened by the damaged spring and is allowing the clutch to slip. Do you have a fixed pulley you can try? That would rule out the clutch altogether.
How can you test how strong the elctromagnetic clutch is supposed to be? I've never really gotten a clear answer other than the testing to see if you can spin it when engaged with SDS and the belt and pulley are on the car. I question how this could be an effective way to determine strength of the magnet when it doesn't measure it at speed.
if i had a leak then i doubt i would be seeing anywhere near 13lbs of boost as a max reading. car runs normal, no CEL, star/das shows 0 faults.
before the spring failure i use to always feel it engage between 2500-3500 rolling into the the power now its only at around 3500 and sometimes it doesnt even feel like it engages.
to me it feels like its not building full boost at low rpms like it use to.
im not sure if its belt slipping or electro magnet issue when the pulley was rubbing, or the springs they installed into my old pulley.
going to pull my pulley again tomorrow as well as bearing , install the new one i got, reinspect and take pics of stuff and see if everything looks normal to ya'll.
14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
Originally Posted by 06cls55amg
if i had a leak then i doubt i would be seeing anywhere near 13lbs of boost as a max reading. car runs normal, no CEL, star/das shows 0 faults.
before the spring failure i use to always feel it engage between 2500-3500 rolling into the the power now its only at around 3500 and sometimes it doesnt even feel like it engages.
to me it feels like its not building full boost at low rpms like it use to.
This is exactly what I'm noticing as well. someone told me it was a spacing issue. I've played with it a bit a found my car seems to like smaller clearance, which leads me to believe my magnet may be weakened. I've been half-tempted to attempt to swap the magnet with a new one just to rule it out but haven't. I'm curious to see what you find.
I have a similar problem as well. using dashcommand to read boost, stock it was 9.5-10 psi .. After installing headers straight pipes to mufflers and EC 83mm pulley its still the same lol, 9-10 psi.
you guys running new pullies? maybe the springs take time to break in idk. hard for me to tell as the weather has been getting colder. after i get back from key west im going to look into this some more
I have a similar problem as well. using dashcommand to read boost, stock it was 9.5-10 psi .. After installing headers straight pipes to mufflers and EC 83mm pulley its still the same lol, 9-10 psi.
No cel either. Its an SL55 not an E55.
With the headers the engine is able to flow better. If you hadn't added the pulley you would see lower boost than stock with either headers or larger TB.
With the headers the engine is able to flow better. If you hadn't added the pulley you would see lower boost than stock with either headers or larger TB.
This is correct.I would check your pulley space from the magnet ..Best way to check this is use a credit card stick it in the gap if its sticks in and tuff it pull out ,then your gap is perfect.
With the headers the engine is able to flow better. If you hadn't added the pulley you would see lower boost than stock with either headers or larger TB.
but there is a chart somehwere indicates that with 83/84 mm pulley boost is at 12 psi ... So 2 psi dropped from headers alone is normal ?
About the pulley gap, ive checked it, its too small that you can't even fit a credit card.
But there was like a scratch under each bolt of the pulley that did not exist before installing it.
10-19-2016, 10:28 AM
car is really bumming me out. 
