TheVazha

I've read the F/S threads and people are comparing them to what a 168mm or 172mm crank pulley in terms of power.

You guys that have done some logging, what are the actual gains? Are they a legitimate source of power or is the crank pulley still the way to go?

If you were to tell me one single thing before I buy one, what would it be?

Thanks in advance for the workshop.

BoBright

guilty

TheVazha

^ nice

Toadster

the s/c pulley is excellent - quicker spool-up, seems to be much safer method of power versus the crank pulley option - love mine!

SPatykAMG

Honestly its a matter of what your after. If your looking for small easy gains the SC pulley is great and you will notice results. However if your after the fast route to power you will get more from a large crank. I plan to run both since you are taking sprung weight off the SC which is good in anyone's book

sircl55amg

its lighter...thats good...but only 1.5 psi more.....is there a dyno proof somewhere ?

GregMB

From what I've read and heard in conversations the success and durability of the smaller upper clutch pulley depends on correct shimming during the initial installation.

I forget the spec, but IIRC there is a minimum of something like 3mm to as much as 8mm. There did seem to be a pretty strong correlation between pulley failures and those guys running large clutch gaps...excessive gaps meant that the spring material that engages the clutch is overstressed and will eventually crack near the riveted areas.

It seems that the guys who were careful to shim the pulley carefully with a gap towards the tight-end of the spec have had good success.

-G

Toadster

I'm making 446 rwhp with just a pulley and EC tune

AMG E Power

I to would like to see a before and after dyno. A 168mm pulley is suppose to give u 30-40whp
And I've never seen anyone gain that on a dyno from the upper SC pulley. I don't think I've ever seen a dyno period with that mod before and after results. Ppl please stare if so

groove66

it is gonna increase HP. But How much
usual rule of thumb is 8-10hp per pound of boost on any F/I car(until you run out of compressors efficiency range) so I don't know why this would be any different..

Toadster

i didn't do a before/after dyno run -but my first dyno run I had a failing H/E pump and put down 400rwhp, after fixing the pump I put down 446rwhp

it's a big difference going from the stock pulley to the S/C pulley - feels like a much broader (i.e. boost comes on quicker and longer) torque curve

I think EC posted a dyno sheet on their site...

given that lots of our cars range from 380-410 stock dyno, I'm pretty happy with 446

E55Greasemonkey

Mine is working great. I don't have a before/after dyno, but my numbers are right where the Kleemann K2 package falls, which is their headers, 168 pulley and tune.

FinanceMike

Search my name. Before and after dyno sheet is on the thread.

AMG E Power

^^^So u got 5whp and 22WTQ if I read correct ?

FinanceMike

Yes, that was my increase from an EC ECU tune to the SC Pulley. Same dyno, same conditions. That was my increase using the box tune that came with the pulley. My only cooling mods are an upgraded pump. Once I added headers and had Jerry dyno tune the car, the HP opened up.

Peak numbers aside, the car had more punch throughout the rpm range after the install.

novae500

Thats odd. Because the conversion for the smaller s/c pulley is equivalent to a 168mm, which would produce approx 40-44 more hp.

FinanceMike

I picked up over 30whp and 30wtq just from Jerry's ECU tune over stock. So if you assume a stock car plus a sc pulley and ECU tune, the numbers are close to 40whp and 50wtq.

HeissRod

40-44hp with just the 168 pulley or pulley + tune?

Toadster

from Eurocharged's website

http://www.eurocharged.com/products/...2-46-16-detail

AMG E Power

been told by cory from kleemann that with a 168mm expect 30-40WHP.
30WHP at the least. this is exactly why i never bought into this "its equivalent to a 168-172mm crank pulley". sure it gives a little power but def not as claimed.

Toadster

someone with a belt wrap kit added 21 more HP just from adding the capability to 'hold on' to the belt better...
this was on top of having a tune and S/C pulley

djrabbi

Probably need a tune and s/c pulley to rune those numbers...

novae500

Someone else posted this info...I can't remember who.

stock==========154mm=10psi(number depends on gear and rpm)
Rentech/kleeman=168mm=12.8psi=+42rwhp
Various========172mm=13.6psi=+54rwhp
VRP===========175mm=14.2psi=+63rwhp
Various========178mm=14.8psi=+72rwhp
Evosport=======180mm=15.2psi=+78rwhp

GregMB

What is the actual diameter of this "smaller" pulley...?

81mm?
82mm?
83mm?
84mm?

The stock pulley is 90mm, but I can't recall seeing a definitive number for what this pulley actually measures....

-G

SilverStrk

Maybe Shardul could chime in on this??