Please forgive the newbness... but I am used to the GM 3.8 Series II S/C motor - been running a modified Grand Prix since late 2002.

I'm a little confused about how the multiple pulley swap works... but not having a Crossfire, I've obviously never been able to dig into the engine, just look at one at a dealership with the engine cover on

With the GP's, the S/C has its own belt shared with just the crank pulley, while the accessories have their own belt on the crank pulley.

We just swap the pulley on the S/C itself to raise boost, but if I am getting this correct, you guys are swapping the crank pulley for more boost?

The reason I ask is, our pulley swaps cost us about $150 nowadays (closer to $300 back in 2003), and yours are costing nearly 6 or 7 times that much, because there are other pulleys you swap. Is there a reason that the supercharger pulley itself isn't swapped? The same system that is used on the GM motor should work for the SRT6 motor, just a question of finding the right pulley sizes. Just wondering why you don't do it this way... does it have to do with the electronic clutch engagement?

I couldn't find much relating to this via search, but if it's a common question feel free to private message instead of bringing it back to the top.

Just trying to get a technical grasp on the SRT6 mill.

 

The supercharger's pulley is a high-tech clutched gadget that would be much more expensive to machine and produce then the alternative.

What's the alternative? Well, because the SRT-6 is run off of just one belt, increasing the size of the crank pulley will speed up all of the other accessories, including the supercharger, therefore making more boost.

The other pulleys included are actually smaller - why? So the stock belt will fit (this is only on some of the pulley kits, I think the 185 requires a new belt but I could be wrong).

I too was confused why I could upgrade a Lightning or Cobra's pulley for $200 or less, but couldn't do it on a 3.2 AMG. I thought it was 'brand markup' because it was a Mercedes part...but it makes sense now.

You basically buy a new Harmonic Balancer (w/crank pulley attached), and 2 new accessory pulleys. I think the price is still a bit outrageous but you have to pay someone for their product so I can't complain.

How did that modded GTP run? I've always liked them ever since I heard a video of one that was cammed. It was a tough sounding 6'er!

SQ

 

Yeah that's pretty much what I figured the answer would be.

The GTP runs great... I dont track mine since I still have the stock tranny, but my friend, who has the same mods as me plus a built tranny with 3.29 gears instead of stock 2.93's runs his... pretty solid 12.6 performer with track prep. I'm sure he could do 12.5 with a little more tuning.

Runs great, but the plastic interior is 10 years old, and made by GM. Hence my looking at Crossfires

 

Many friends have LS1's and they are understanding what I meant when I mentioned the plastic interior 6 or 7 years ago when they bought them.

That's quick for a GTP...you always have to be cautious of those guys on the street because several are sleepers. There is one around here that was laying down upper 12's consistently a few years back.

SQ

 

I believe i've read somebody out there is selling a single pulley that is the same size as the oem pulley but has less mass therefore spins faster giving you more boost from the s/c. Also you can use your oem belt. Does anybody else have any knowledge about this type of pulley. I didn't mean to highjack this thread, i hope nobody minds. ILLCYA

 

If it is the same size, then it will spin the same speed. Although the mass will possibly allow it to rev quicker, the overall speed would be the same.

The only way to increase (or decrease) the speed would be to change the ratio between the pulleys in the system. To do this, you have to change the size of one or the other.

SQ

 

I totally agreed. The only way to increase boost is to change the pulley's ratio. The LETs Pulley is larger and weights the same or less than the OEM pulley.

 

Check out this thread: https://www.crossfireforum.org/forum...ad.php?t=22396

 

I know some Pontiac people .....and I mean the new generation not the old like me!
they own one of a few...just like our srt's. As in pace cars.
I will tell you this with no mods and if ya know how ta drive ya can pull a 12.7 in a SRT all day long!
Try that stock in something else!

 

Does anyone still have their stock pulley they would be willing to part with?