aganzon

That's next on my list.

jangy

It won't help. It looks good. If you wanna help that end, open up the restrictions. Big differentials in pressure from the start of the snorkle to the end.

jangy

Either way, I'd upgrade the cooling with TB or header. I'm going to go the cheap route and just install the marine pump and have it wired to run all the time for now. Then, I'll find one of these custome jobs running around that I like. The budget on it is $2000, so none of the prefabbed kits will do. Worst case, I'll go with the Evosport one.

GoDav AMG

Are you planning any ECU mods at this point? What year car? If it is an '06, I wouldn't bother until you have done more work.

Why not?

jangy

The car already runs rich. Adding just a pulley will only help get it into a better sweet spot. More mods (even more air) would finally get the car running lean, so a tune would be needed.

jangy

Don't forget that MB kept the same Pulley and manifolds They just changed TB and claim a 37hp gain.

Edit: on the '07 SL55

aganzon

yup, yup, yup.

aganzon

Yes...in the interim, a Johnson CM30 or 90 pump. I hear the 90 is a SOB to try to fit under there.

Anyone try the CM90 and have pics to show of their install?

SLK55R

you could always look into Supersprint headers and cats. That way there is no cutting for you. Its expensive though but I got to say they look AMAZING. Adam has done a couple already with ZERO check engine lights.

Also I'll disagree with chiro on the headers not making any sound difference. I think they do slightly and even more so if you change out the cats to 100 cells.

I'd do the cooling after Adam does Rocket's car!

aganzon

I did some seraching and found this thread referrenced by Vadim@gmgracing showing a CM30 install. It seems the CM90 is a lot more work for an interim solution.

https://mbworld.org/forums/showthrea...78#post2376178

GoDav AMG

What size is the TB on the 07 SL55, is it the same as the V12 in size.

jangy

I dunno about the V12 TBs and if they are compatable. The '07SL55 TB is 80mm.

GoDav AMG

Thank you the info

aganzon

All,

Attached is my first dyno run. Ran it this afternoon in 89.3 Deg F. after an hour+ drive in SF Bay Area traffic getting to the dyno. Tried to cool it down beforehand but probably didn't help all that much. I'm not sure what these other figures mean:

29.6-0.27in Hg.
CF=1.01

Completely stock, no mods what so ever. Probably heavier wheels cuz the stock wheels were chromed. Jangy - 390.8 RWHP seems low? TQ seems higher than average @ 477.3?Anyhow, everyone's thoughts about the run and whatever the two figures above mean are fully welcomed.

chiromikey

"in hg" is barometric pressure. "cf" is the correction factor used.

390.8rwhp is typically low for a dynojet...probably because your afr is one of the worst i've seen. even though the operator seems to have shut down well before redline you're already losing power. some may suspect s/c belt slippage, i would also suspect iat's. it could even be a traction issue.

any idea what gear you were in?

aganzon

Thanks!
No idea what gear it was in. Adam was there...may be he can shed some light. Adam?

ROCKETW19

that dyno has jacked up air flow readings (i suspect) also im with chriomikey i bet your IATs were up there before you even ran the dyno. PTE has a 160 therostat that will help some untill you decide you wanna coolin kit. dont worrie about the dyno numbers to much they are all different and you cant compair yours to some other machine. use it to gauge your mods.

aganzon

Yeah, I think you're right about the IATs. never really got cool enough. You're also right about not getting bog down by comparing with other's runs. My main intention was to figure out if the car was healthy enough and to get baseline figures before I start my mods. With the TQ figures, it at least tells me that my tranny is healthy and getting the poundage to the ground. As I mentioned, I am getting the 178 pulley/ECU done and have also decided to go with the RT headers and CM30 pump followed very quickly after with the TB.

I hope to get it closer to 475RWHP/555+TQ.

AdamG@NorCal

It was done in 4th.

The temp is 89.3 deg but the IATs are much higher than that. Probably +20 deg higher.

chiromikey

beginning run iat's are 20* above ambient...iat's during the run are much higher than that, guaranteed. how much higher is the million $$$ question.

AdamG@NorCal

Yeap, freaking san jose is always hot! How's arizona weather? Is it very hot out there?

chiromikey

we finally had a sub 100* day today!!!!!!!!!!!!!!!!! another month and we'll be down to high 80 temps with a tolerable da in the 3000' range and i can get back out to the track.

ROCKETW19

i agree the million dollar question is how hot?
i say someone make a sticky sayin your first mod should be a data logger that can at least read/record IATs

zoink

I think yours is healthy.... even healthier than mine, except the A/F

391whp, as other mentioned, seemed to be because of the heat. Here are my numbers and some factors that I could remember as comparison.

Temp: Around 75-78*
Car was driven from Adam's place to the dyno place.... according to him, lots of quick bursts and holding at 100+mph for 10-15 sec.
Cooled down for 15 minutes before 1st run & 2 minutes in between runs.

4th gear, dyno mode.... reached top speed at around 5.5-5.6K RPM:
1st run (approx. - give or take 1-2whp/wtq): 417whp/470wtq
2nd run (got the chart ): 407whp/460wtq
3rd run (approx. - give or take 1-2whp/wtq): 395whp/452wtq

So you could see that the heat robbed about 10whp/10wtq every run. And I believe your chart is from 1st run (.001 on file name).

Three distinct things when I compared my chart w/ yours:
- My torque curve is not as flat as yours in low RPM (<2.7K)
- Your HP curve goes down above 5K, while mine still goes up but w/ flatter slope
- Your A/F curve is steeper than mine. Mine is 13.5 (2K-2.2K), 13 (2.2K-3.5K)... until only around 11.75-12 above 5.2K.

So dyno experts out there may be able to chime in.... same place so difference in dyno machine should be minimal, if not non existent.

I'm particularly interested in knowing (hope they're not dumb questions ):
- Why aganzon's A/F is a lot steeper? Does weather really play a major role or something else (i.e. S/C belt, air filter, etc.)?
- Why my torque curve was 20-30 below maximum at low RPM (< 2.7K) unlike aganzon's? Is mine more typical than his? Or is it an indication that my car has too much carbon build-ups or my tranny is less efficient than aganzon's or ...? Adam believes that I don't drive hard enough to minimize carbon build-ups

jangy

The 390 is a bit low. I expect anywhere from 406 to 420 on a stock E55. Weight from chrome is nothing. The IATs are HUGE. Especially if the car sat before or if the dyno shop didn't have nice ventilation.

RennTech Headers, huh? GGGGrrrrr!!