Fixed Pulley Discussion
who tuned your pulley?
who did you buy it from?
how long have you had it (miles)?
any problems or noticeable changes (besides power bud)?
Pros:
- Less expensive
- Less weight. (Probably negligible but who knows, any ones input here is likely just speculation.)
- Slightly better response. (Also, I feel that any difference is probably negligible.)
- No more clutch engage hick-up at low part throttle RPMs from using a small clutched pulley.
- A lot more at idle heat. IATs at idle with the clutched pulley never really exceeded 120. I have let the car idle at a grocery store while my wife is inside for ~20 minutes while I had a napping baby and hit ~145 IAT.
- Significantly less cool down at the track between runs. With the clutched after parking for a while and sitting in staging IAT usually would start at just under 120. With the 72 fixed the creep up to >130 fast. (I currently have a CWA50, frozen boost heat exchanger, and meth. Upgraded to two CWA50s and a DTK monster heat exchanger at the moment, may be better after. While on it meth keeps temps in check no problem, its just the fixed pulley keeps the heat coming at all times really)
- Cruising IAT went from ~15 above ambient with clutched to ~22 above ambient with fixed.
- Fewer tuning options. (EC does not tune for fixed)
- While the small clutched pulley engage hickup is gone, there are some times hickups(more like a slight rev) where the clutch would engage, I assume due to the operation of the bypass valve in cunjuntion with the always engaged clutch. Not much, but something to note.




I change bearings associated with the serpentine belt and idler pulleys every 60,000 miles. By 90,000 I've had them failing. The rear bearings in the supercharger will now become a maintenance item.
FWIW, YMMV, yada, yada, yada....
Pros:
- Less expensive
- Less weight. (Probably negligible but who knows, any ones input here is likely just speculation.)
- Slightly better response. (Also, I feel that any difference is probably negligible.)
- No more clutch engage hick-up at low part throttle RPMs from using a small clutched pulley.
- A lot more at idle heat. IATs at idle with the clutched pulley never really exceeded 120. I have let the car idle at a grocery store while my wife is inside for ~20 minutes while I had a napping baby and hit ~145 IAT.
- Significantly less cool down at the track between runs. With the clutched after parking for a while and sitting in staging IAT usually would start at just under 120. With the 72 fixed the creep up to >130 fast. (I currently have a CWA50, frozen boost heat exchanger, and meth. Upgraded to two CWA50s and a DTK monster heat exchanger at the moment, may be better after. While on it meth keeps temps in check no problem, its just the fixed pulley keeps the heat coming at all times really)
- Cruising IAT went from ~15 above ambient with clutched to ~22 above ambient with fixed.
- Fewer tuning options. (EC does not tune for fixed)
- While the small clutched pulley engage hickup is gone, there are some times hickups(more like a slight rev) where the clutch would engage, I assume due to the operation of the bypass valve in cunjuntion with the always engaged clutch. Not much, but something to note.
would you recommend me to get a 77m clutched or clutchless after cooling mods
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.... well.... you CAN remove the clutch from the SC but there is no reason to, and it's hard and a waste of time. No one does.
so if I put clutchless that means I can still put on clutched no problem? I read so much about people saying you would need a new supercharger
Honestly you will get better answers if you spend time reading. So many posts and questions come up that are utterly useless because it has already been asked and the knowledgeable guys are repeating this info to you.
Put a factory bearing back in, if you couldnt notice the sound of your factory pulley literally sh*t its bearings out then you really need to familiarize yourself with the vehicle.
Honestly you will get better answers if you spend time reading. So many posts and questions come up that are utterly useless because it has already been asked and the knowledgeable guys are repeating this info to you.
Put a factory bearing back in, if you couldnt notice the sound of your factory pulley literally sh*t its bearings out then you really need to familiarize yourself with the vehicle.
Most posts are from when it was introduced I need experienced members with the product. I don’t understand with the need of forum members to say search when some people already have lol. We just want up to date answers.
Countless days of research and you thought you couldn't put a factory pulley back on? Dont be so lazy expecting everyone to feed you the answers you need. Take your time...Be literate with your posts...and really contribute to these forums.
Yes I read no where you can put it back on, someone told me you couldn’t. Lazy? This is a discussion thread about owners with fixed pulleys you jerk 😂
Does the clutch not react quickly enough for you? As soon as you tip in the throttle it's right there when you need it? Sorry, I can't see the minimal benefits outweighing the cons unless your trying to build a dedidcated
1/4 mile drag car. In that case go buy a Big Block Mopar.. just my 2 cents.




