Im looking to ad a 19% supercharge pulley with 2% crank pulley. Is it a good combination????

 

No. Belt problem and more heat....

 

Ditto. A 19% S/C pulley coupled with a 2% crank pulley is going to be way too much of a reduction. In the case of these M45 superchargers, more is less. Because the more you raise the boost, the more heat you generate which defeats the purpose of running more boost in the first place. And as stated you'll have issues keeping belts together as well.

 

What about 15% pulley with 2% crank pulley??

 

That would be a much better combination that a lot of folks run with success.

 

What belt should be used with a 15% pulley and a 2% crank?

 

I have had my 15% Craven and 2% Alta for 3 years now without any problems what so ever. I personally think the 19% and 2% combo is a bad idea,heat is your worst enemy in Supercharging.Just my 0.2 cents worth.
B.

 

Nascar- I was wondering if you had have your mini dyno. Just wondering what HP you are at with the 15% & +2. That what I am going be installing soon. also what u reading for boost?

 

A 15% + 2% will yield very similar results to those running a 17% and 0% such as myself. Probably somewhere in the ballpark of 15-17psi depending on how healthy your supercharger is. I know in my case I can get just a hair over 16psi under certain conditions. I do think the 15/2 combo is easier on the belt than a 17/0 setup because the belt will not be forced to bend as tightly around the pulleys.

 

No....
too much boost...heat....not enough fuel.
22% reduction or the equivelent of....
with 93 octane and a 17% you run lean at higher rpms....but not dangerously ....with a 19 some do ok...some don't....
Even with a custom tune at install, all the heat you will make with the sc will be couterproductive....you will make LESS POWER THAN A SMALLER REDUCTION.

 

Just go stright to a 17%....
if you want a 2% ....br sure to get a dampened one....the cheap ones are not...
If you live in a warm area....a 15% may be a better option....if the charge air is too warm, the timing will be retarted..same with octane...not enough...(like with. 91) 93+ is great, you will make less hp..(with lower octane)..if you cannot get 93...91 is kinda iffy imo with a 17

 

+1 same here for 4+ years no problems

 

One thing yo consider....when running a 2% underdrive, the alternator and ac are both getting ovrrspun a bit...causing a bit of extra parasitic loss, and shorting their lives a bit....you can get a different alternator pulley.....
The lighter crank damper can improve throttle response a bit, but a 17% is a simpler swap....if you need anew crank damper, than a 15% and a 2 is ideal for many...if you want to run a 17 and are willing to take a tiny risk with the above items..on a dampened pulley.....running an undampend pulley starts a whole new discussion....
The above chart is not 100% correct, but pretty close.....a few different sizes are preceded, but the 535 fits a 15 or 17% reduction, whith an overdrive crank damper...not sure...

 

CZ, seeing a tad over 15lbs boost. Had a tune early on but have since done more mods and need to retune/dyno.Now with this head,cam and injectors,i hope i've bumped her up a tad.Stay tuned!
B.