kustom2k1

OZ, great stuff. Watched the AeroTurbine vids along with your exhaust, sounds like the old v8 Ferrari. Parts biz, I agree, you have to build a following to be successful. I think the sound more than the performance in most cases sells an exhaust. Get that right for the SL and 2k shouldn't be a problem.

As SL55 owners we should consider ourselves lucky Mercedes expanded on the platform to include the E55, only reason we still get performance mod/upgrades for our cars. Its up to the individual, the weekend warriors to expand the performance envelope, like Shardul and Brooke....sooo, OZ, get crackin!!

@king, Whats up, hows the car treating you?

Hulk, torque is good..well you should know.

shardul

iTrader: (1)

+1 for OZ

Hulk

Yes tq is good! Did you get the neck brace off yet lmao

On the exhausts, yes, it's true it seems sound sells more than the actual performance

kingnash

kustom - installed lower links and forgestars cf5s 19x11 + 19x9 + hankook v12's. spent alot of money on service and repairs and still got probs (new consumer batt + service a + full tranny service + abc flush + fixed vent chamber leak + replace leaking strut with arnott strut). paid stealer to install arnott strut and it still leaks! i sent it back to the stealer, waiting on a response now. on top of that i lost my %#$% key! stealer is gona want like 400 to replace.. any alternatives?

so if i install kleeman shorty heads will this help with the back pressure?

kustom2k1

King, man the first sentence was all good, down hill from there! Lets see some pics of the new shoes. I hear losing a key can be expensive, why dont you have a spare set? So you purchased a new leaky strut from Arnott. WTF? Arnott should cover the expenses since they sent you a bad strut.

Lets see the pics!

overZealous1

the backpressure needed for a s/c engine is primarily a myth. now, and n/a engine, it can benefit from some backpressure. i have done research and found no conclusive evidence that back pressure is a beneficial thing when running any type of f/i.
to keep with the hp numbers in the Z community, we did also make a dual 2.5" system that the sc guys would run. but, the sc airflow would limit to about 450rwhp. the turbo cars were doing 600-700rwhp.
if you have a halfway decent exhaust, you will be running nearly zero backpressure at low rpms. might go up abit at part throttle or lower accelerating rpms. but when you are at full throttle, full boost, and in max power range, that back pressure will hurt. i guess it comes down to possibly getting a little more torque around the peak, or going for all out hp.
in my testing, i ran both the 2.5" and 3" duals on my built motor tt 350z. throttle response was maybe a little better around 2-3k rpms, but you could really tell a difference at higher rpms the 3" was stronger.
now here is an idea. but, it would take some time and testing (which equates to money, haha), but if you ran dual 3", put some electric bypass valves in the 3" tubing, then did a diverted 2.5" bend around it. actuate the bypass valve via boost in a progressive manner, and see what you come up with. normal operation would use the 2.5 diverted bend then back to 3", then when mashing on it, the bypass valve opens up the straight 3" section again. this would create a truely progressive exhaust that could theoretically flow along with engine requirements.
one problem, unless anyone has figured out how to run a trigger off of, or more importantly create a 2d map (for the sl that is), you couldn't accurately control the bypass valve when you needed it. doing it via boost would get you close, but not all situations would be handled. then ofcourse, the chance it doesn't help at all or, you get 10 more ft lbs in the torque peak. haha. i think an n/a motor would see more benefit than an sc.
ok, now my head hurts. i think i will approach it like this for my car. do upper and lower pulley, add nitrous, and dual 3". if it feels laggy in the mid range, i will give it more throttle! haha.

Hulk

The backpressure is only needed on initial take off, after that it needs free flowing, if you look at the ZR-1 mufflers, they have a flap that opens and closes and that is to maximize the tq at take off and then free flow, I have done alot of homework on these engines as well with my fab guy, who actually is a pro at SC engines....the setup I have now is very similar to the ZR-1 exhaust, hence I get monster tq and free flowing after take off, just ask Kustom, that's why he needs the neck brace lol

Havoc

The ZR-1 mufflers are an exact copy of the Z06 LS7 N/A mufflers, the only difference being the baffling inside which gives the ZR-1 a deeper tone. The valve (flap) opens at WOT, so if the throttle is smashed at a dead stop, how is TQ maximized at take off if the valve is open?? The valve is not there to maximize TQ at take off, but rather to provide a free-flowing exhaust a WOT. Ask me how I know..

Havoc

Good to hear, thanks for posting and sharing your experiences!

My belt wrap kit and smaller S/C pulley just arrived. The S/C pulley is going on an SLR blower I purchased along with a 178mm crank pulley!!

Hulk

They don't give free flow instantly, ask me how I know

All that's needed is the initial backpressure, even 1second before it starts free flowing

Next time you get a chance see when you mash the pedal

We have actually done testing with a free flowing muffler and the ZR-1 mufflers..

More than 10 wtq

I know it works for my setup and I will let everyone know for sure when I get that 10 sec slip this winter

Let us know how that SLR blower works out

Havoc

Dude, I have a Z06 and played with it many of times to know. I also purchased the ZR-1 mufflers to install, but sold them after learning that they were the exact same as what I already have just different baffling. Must be funny how the ZR-1 gains HP and also TQ with aftermarket free-flowing exhaust and mufflers.

That SLR blower is going to work out just fine buddy!

Hulk

I know for a fact what difference it made on my E55, like i said i have similar ZR-1 mufflers,I'll disagree with you and you can disagree with me and leave it at that!

The sl has different mufflers than the E anyway

overZealous1

until a true test is done, which sounds like you may be able to do with your set up hulk, if yours is variable like that. one run with valves closed completely, one with them open the entire time, then one in the variable mode. only way to really tell. until then, i'm going with all the other engineers and engine builders that having back pressure is not a positive for any type of f/i. not trying to conflict, but, after lots of research, have found no evidence. you could prove everyone wrong if the test shows a benefit! lol

overZealous1

havoc, since thread is completely highjacked anyways, do you know at what point that compressor will lose efficiency, or max speed will be? Im just curious how fast we can actually spin these things.
sounds like you may be testing that with upper and lower pullies, and an already overdriven case! lol

Havoc

Depending on the cooling mods installed, it seems that a 190mm+ crank pulley or a 180mm crank pulley plus the smaller S/C pulley is creating an inefficient S/C.

My plan is to replace the stock intercooler with Evosport's Top Mounted Intercoolers which increases the cooling effiency of the stock S/C set-up. I don't know if the stock S/C will still be efficent with all my mods until we have it actually running.

overZealous1

i have a 180mm pulley on the way, and was going to pull the trigger on a smaller upper pulley too, but, toss on meth injection triggered at like 12psi or so. it will help cool intake charge abit, but most benefits will happen during the burn. or should i say, help in preventing an explosion. haha

Hulk

I have tested it already, the E55 mufflers are very bad, very constricting , so I put on free flowing while I gained on hp I lost tq, so after researching and talking with my fab guy(who kustom knows very well also) we decided on a similar setup to the ZR-1 mufflers, and low and behold I gained my tq back and 10 more and my hp gained as well, I have modified manifolds into full 3inch exhaust with H pipe...

On to the next question...

Cooling is imperative.. I have a 180 with SC pulley and have modified my cooling big time and my iats stay in check even in 90* weather

Will doing final tuning in a few weeks andnwill fine tune it for the winter

kustom2k1

Just dont talk about politics.


Check out this SL55, belongs to Sal (Urnext), its the fastest/quickest SL55 I know of.
https://mbworld.org/forums/w211-amg/...s-sl55-vs.html

His combo
https://mbworld.org/forums/w211-amg/...-pics-etc.html

overZealous1

ya, i have run across sal's car before. one of the reasons i bought this car. relatively not alot of work needs to go into them to make them a pretty fast car.
i am going to take a shot at his time, if i don't get it after the first round of parts, i will give it one more go. either i will take it, or they will be picking up engine and tranny parts off the track from running too much nitrous. haha
i think the tracks are about to close here for the season though. gives me winter to come up with some goofy combination.

kustom2k1

OZ, good luck. Its going to take a lot of work. Long tubes, 82mm TB, 180+ size pulley, Injectors/fuel rail, trunk tank filled with ice, light weight CLK rims and skinnies, race gas tune, lighter battery, remove seats and replace with a single race seat. That should get you in the ball park.

I'm missing the 82mm on the hardware side, but I'm waiting for the release of the 90mm. Not shooting for the record, 11.00s would be satisfying enough.

Nitrous would save you a lot of time and money.

Hulk

This winter I see low 11s for you bro

kustom2k1

Its been a long rode, fun, nerve wracking at times and definitely a learning experience. Payment consisting of quick pass will suffice in the end. Custom plate will read "sasafid".

Hulk

Lmao

overZealous1

ya, just looking at nitrous to pull the rest of the way. it will ride right over the expense of all the other breathing mods and time. don't need it to run 10's all the time, just once, lol. one thing that has me a little scared, is i havn't heard or seen anyone breaking anything. it is good, but, at the same time, it is almost better to know the limits than not.
btw havoc, read your build thread. sucks to have to redo major things like that. have you swapped forged pistons into the new motor yet? anyone know the limits of those? i forgot to look at ringland thickness. thats usually the first to go.
i have a pretty brutal ground up build i am doing on my other car, but having fun with this car right now. the new to me thing still.

overZealous1

well, after spending some time looking at pics of havoc's torn apart engine, the stock cast pistons look very stout. first and second ring lands are thicker than the forged counterpart, and alot of material around the wrist pin area. rings are thinner though, but keep your a/f right and it would be ok.
head bolts separated by coolant passage to cylinder, will help eliminate need for torque honing or cylinder distortion, atleast in upper portion of cylinder where sealing is most important. piston squirters to help cool pistons. 4 bolt mains. rods look pretty beefy for a stock piece, forged crank. open deck, but atleast cylinders are siamised to eachother to help with movement and gasket leaking.
let the nitrous fly!!