CLOSED: NST TRD/ Magnuson 4.0 supercharger lightweight billet crank pulley | crank dampner

My 2.3 would disagree with this statement. The MP90s max RPM efficiency limits is somewhere around 18,000 if I remember correctly. It's been a long time since I looked into that.

I'll update you on the list.

 

My 2.3 definitely has more jam than my 2.5. I'm also at elevation though so efficiency might be the same as a bigger pulley at sea level.

 

I am at sealevel and I can say firsthand my 2.3 definitely shows a largely notable jam over the 2.5.

 

Airflow at peak rpm between the 2.3’s and 2.5’s are surprisingly similar. In the midrange that’s another story.

 

My butt dyno agrees with that assessment. It absolutely spools up quicker

 

Interesting. That makes a lot of sense and I can see that being very true. It is a lot faster at mid rev.

Hell yeah brother!

Sorry, I was just dying to say that.

 

@White lightning boosted

 

I'm in process of reading this entire thread. Add me to the list. I have a few other spendy mods I'm working on so any delay in payment would help.

 

Right now we are still in the R process of the R&D for it... It's a slow going thing because the pulley we want to replicate is obviously on the trucks and since it is a main pulley which is not easily replaceable it is not just as easy as like oh okay let's pull it off and measure it. No we still need to get a CAD of it and then we can start tweaking with the design for further lightening purposes. And CAD is past my skillset.

I thought I had some CAD files for it, but it turns out I had some Hilux files which funny enough are of the 6 rib pulley style design and it is uncertain weather or not it was a dampner drawing or a supercharger pulley itself.

 

Past my modding needs for now but enjoying the show.

@12TRDTacoma Wouldn't this also act similar to a lightweight flywheel which can have negatives as well as positive? Or is there enough other counter weight on crank itself?

EDIT: Second question since it was deemed not a stupid question.

70 oz vs 14oz is a big jump in weight but is there any normal resistance added to the motor just by adding the S/C? For example if the S/C adds some resistance to the crank that wasn't already there (maybe rough estimate of rotational mass of the blower blades? ) maybe the jump in weight isn't as bad on the crank as suspected???

 

Good question

 

I'm in process of tracking down a contact my dad gave me. He has watched this guy take a billet block and make a custom high rise intake manifold for a race engine.
No guarantee but this guy sounds like he potentially has the means to get this done.
FWIW I'm in favor of the extra effort in a 6 rib design.

 

Same. It can be done

 

The dampner and the supercharger crank pulley are one once unified on the setup. It is mostly redundant to run one lightweight billet and the other pot metal as the effects of the lightweight design are mostly counteracted due to the additional weight being added to it. By lightening 100% of the pulley setup it allows for a setup faster revving as a whole and as long as both are balanced and designed correctly there is no need to worry about any further issues.

This would not have the negatives of a lightweight flywheel as the flywheel is a large major rotational component in the assembly. As long as the crank dampner is correctly balanced, the rest is all gravy.

You are correct, this would be similar to a lightweight flywheel in theory, not in size of course.

I hope I answered the questions for you.

6 rib is WAY more trouble than it is worth. I and we have investigated it. Trust me, you won't be happy and will spend a ton of money venturing after a fruitful mod which will deem ultimately fruitless.

 

Ok. 5 rib is fine too. I'm getting pretty good at cutting belts anyway.

 

@Murphinator had a good idea about pooling funds to buy a s/c drive pulley for this. Where are we on that? We could always put it up for sale on ebay when we're done to reclaim funds.

 

With a larger pulley there would be less need for all these grip mods as the main crank pulley now gains better belt wrap on and since that is where the major wrap is occuring, increasing the size will always increase the wrap in the process along with a side effect benefit of additional boost added.

A new crank pulley would be some $130 with a wait time of a week from Magnuson direct.

If we had a bare pulley which is off truck it would be easier for @XPOTRPR to make the measurements and CAD needed to move forward with this, however, I sort of see this as a pointless expense since we all have the pulley already.

We have to exercise patience here because we are now approaching mods which have never been previously done before.

 

Patient I can be. Just looking at it so nobody had down time on their truck. If 10 guys pitched 15$ it might seem light in expenses for all.

 

I have talked to XPO and he has no issue with (and is willing to) taking his truck apart for a bit to take some measurements, photos, and CAD stuff. He did say it would be a little bit though because he has been out of town so we are at his mercy new pulley or not. It's really just a waiting game.

 

I'm so glad one of the 3 gb I'm down for has a little patience. My credit score thanks y'all