Supercharger Quick Change Pulley

For anyone who likes to mod on their blower, I am taking steps toward becoming the guinea pig.

Our TRD blowers are based off the Eaton M90 but the shafts used at the snout appear to be of the same dimensions as that of the M45. The only difference between our M90 and the 3800 series L67 based M90 (Grand Prix GTP, Monte Carlo SS, Impala SS etc.) is that theirs uses a 6 rib/groove pulley and ours uses a 5 rib design.

I was not okay with running a higher groove count pulley compared to the rest of the system. The possibility of the belt jumping teeth and shredding itself prematurely increases so I had to search for another solution as I did not want to sacrifice system reliability.

I went ahead and took some measurements today of the blower's pulley offset, as well as shaft diameter and it lined up near identical to that of the pulley which is used in the M45 Eaton supercharger used in the Chevy Cavalier/ Sunfire and 2.4L engines used in some GM cars, which also coincidently uses a 5 rib pulley design. Yay.

In taking these measurements I went ahead and ordered a quick change pulley kit from Pulley Boys based out of WA (PN: 5QCK) which will allow you to press on a hub adapter which then allows for a quick bolt on pulley design eliminating the need to press on a new pulley every time you want to do a swap out and potentially damaging your pulley upon removal as well. Turns a hour long job into a 10 minute job including taking the belt off.

I receive the pulley and tools needed to do my swap by Friday most likely, so updates on how this pans out are soon to come. Options are ALWAYS a great thing to have!

Picture of design:



FINAL UPDATE: This mod WORKS on our blowers! Please see page two for my final thoughts and footnotes. You may need a size down smaller belt to prevent boost loss if switching to 2.7 or smaller pulley. Dayco PN: 5PK1765 will be what you want.





Edit: I suspected the belt slipping due to stretching recently. So I went ahead and took the steps yesterday to perform a RIP mod on the pulley. Belt slippage will no longer be a factor.





There are a lot of questions surrounding up to what point you should cut your snout, cut up to this silver line on the side.

 

Interesting. But how often do you actually expect to change pulleys? Since its part of tuning I would think infrequently???

 

Since you have a '12 I assume there is no tuning going on. So no need to swap pulleys. Just get a URD pulley. Install it and be done with it.

 

The stock TRD tune is so pig rich more often than not that it is a great idea to lean out the system. Ideally no lower than 11.5 AFR (12.5 AFR preferred) at wide open throttle is best to avoid fuel dump situations. Not only that, if you run that rich, you can and will foul out your expensive iridium plugs out much sooner requiring replacement.

By having the ability to swap out pulleys whenever you please with ease, you give yourself the ability to further fine tune your air fuel ratio. Given that myself and many other blower owners on here either peg our AFR gauges at wide open throttle, or run somewhere in the mid 10's even after installing aftermarket intakes, and exhausts to further less bottle neck the system and attempt to lean out the system some, this is a great option to not only make some extra power quickly and in an inexpensive matter, but clean up our running condition without requiring to be retuned.

Oh, and there are better options for custom pulley sizes.

 

I am not satisfied with that option. For reasons previously stated.

 

Ok I see.

So your version of tuning is to keep the trd "rich tune" and adjust AFRs by swapping pulleys and adding boost?

Not the safest idea, but I'd be interested in seeing your results.

 

The whole point here is to have options, and as you and I both know, options is always a good thing, as they seem to be very limited to our trucks in general. More so when we are talking about the boosted trucks.

I like this design because I don't like the idea of not being able to remove the pulley easily and being presented the risk of damaging the pulley upon removal. If you have a URD pulley the risk of bending that pulley upon removing it from the shaft increases as it is made of aluminum. This allows you to get any size you would like and test it out. If you don't like what you are seeing, either tune if you have that capability with UCON, or APR, or whatever and clean up that way or do what is necessary, or just simply go up to a size you were previously running. No longer the need for two sets of hands and having to boil the pulley in scalding hot water, or baking the thing and having to do hasty installs before it cools down. This makes things easier and I don't know about you, but I like easy.

 

Plenty of tuning available for the '12-'16.

Good find! Which size pulleys do they offer?

With this piece, it would open up the doors to a lot more owners swapping to different sizes.

The next question I have, is that i have a strong feeling that the hand powered snout machining tool should be used first. Since the 2.7" ( or any size smaller ) requires the snout to be trimmed down. Sold by URD.

 

The hand powered snout machining tool can either be obtained by URD, or ZZPerformance. They are the same exact tool. I picked mine up from ZZPerformance.

The sizes available for the 5 rib design are 2.8, 2.7, 2.6, and 2.5 I believe. If you want a different size, all you would have to do is place a call and request they make you a different one. The advantage to going with them is that machining metal is their business and that is all they do all day so making a different size would be a non issue.

Personally speaking, I really love the idea of a one time press-on-and-forget hub.

I receive my items tomorrow actually. I am getting both sent to me priority mail so it is a two day ship deal.

 

Yeah, most people recognize URD over ZZperf, so I was just saving time. Lost it now though. Lol.

get the 2.5".

 

Hahaha

Yeah I know, just giving people all the options so they know.

I am actually.

 

That's for cruising and N/A fool.

You need a boosted chart.

 

Do you got one yo? Lol.

I'll have to delete that last post than! Don't need any more misinformation than what is already floating around.

 

I'm not sure how I feel about removing all the drama/excitement/stress from swapping pulleys.

But I am seriously interested in the outcome as I already want to go smaller, without the headache.

 

I'm curious if the snout cutter would have clearance for a 2.5 pulley. Maybe

I remember when Jap on xru showed us zzperf back years ago and used the snout cutter first. Prior to him everybody was sending the blowers to CNC machines. Whatever happen to him @Torspd ?

 

Updated: I removed the previous chart and found another one online which refers to proper AFR's for boosted applications. Trouble is, I don't know what 8-13 PSI is considered as on these blowers, low/ medium, or high boosted levels. Maybe @Torspd can answer this one?

The whole reason why I begun searching for a quick change pulley setup in the first place. When I dealt with installing the 2.85 pulley it became a small nightmare and sweat-fest wondering if it was going to stop midway and seize on the shaft like it did for me the first time. I don't ever want to deal with that ever again, so why not simplify my life some and endure this nightmare one last time for good purpose.

Just like those funny guys on YouTube always spamming with the follow me comments at the end of their videos. Make sure you smash that Subscribe button and stay posted for the latest updates!

I receive the kit and snout cutter tomorrow and will be installing it either Friday or Saturday!

I don't see why it wouldn't honestly. It seems to mill quite a bit off of the snout from what I have seen in order to accommodate room for smaller pulleys, so it should be just fine!

Nice to have you following this thread Tron. You are one of the few I know running your pulley size in the group so it is nice to have a small backing group.

I have been doing a lot of math to determine blower speed to ensure it will remain efficient enough to stay inside the max RPM range before it becomes inefficient and what I found is that there more than enough room to grow, even at a 2.5" pulley.

These blowers are based off Eaton's latest Gen V (5) tech and are much more efficient over previous models. The fact we come supplied with Air to Water intercoolers with the supercharger kit initially allows for plenty more room to grow in boost as well over the factory 6 PSI 3.0 pulley.

 

Started working for Mighty Car Mods?

 

200 kpa equates to ~14.5 psi on the psi on the boost gauge.

100 kpa equates to "0" on the gauge.

 

Oh yeah, see then. 11.5 to 12.5 will work just fine as I was originally saying. Even 11.5 would be considered just a bit rich accord to the chart. None of us is going to be crazy enough to shoot for more than 14.5 unless we have either a death wish or have built the piss out of the engine. Lol. Good to confirm it off a chart though.

I hate working with Kilopascals. Lol.

 

Just to note, the 1GR needs to run rich. Cylinders 5&6 run hottest. There for the richer mixture helps prevent that notorious ring land destruction caused by spontaneous combustion. In the 1GR world, on petrol ( non E85 nor race gas) low 11's is best when anything over 1 psi. Lol. Better safe than sorry.