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

Whats done is done... but these little issues are what I was trying to get ahead of when designing and initially planning on machining these pulley's.. and why it was "taking so long". It was to avoid potential things like this. This is what drives machine time, and cost up. Not sure why they didnt do any test fits, maybe they cant hold tight tolerances like we can.. I also would have used a dowel pin vs a roll pin. oh well, you get what you pay for. it is what it is. we'll see how they go..

 

what about swapping the dowel pin from the magneson pulley?

 

That’s what I did for my setup. But I think the dowel pins are smaller in diameter than the roll pins. Could be wrong.

@12TRDTacoma you happen to know the thickness of material where they drilled out the holes?

 

I recall that being their requirement, years ago.

 

No way in hell do I know how big that hole is.

I could always ask them, but even then. I really don't see much of a benefit in going with a dowel pin over a roll pin. The primary function of that pin is just retention of the pulley, the bolt does the critical work once both pulleys have been joined.

I mean at least that's the way I see it. Am I wrong? Potentially, I'm no engineer, but I personally think there may be some overthought as far as this pin thing goes.

 

the transfer of force from the crank to the SC pulley is solely against that rolled pin, just like a shaft key. There is no other way to transfer force other than simple friction between the two pulleys. The crank pulley is keyed the same way to the crank.

 

Do you really foresee it being that big of a deal? I'm not asking that in a smartass way, but in a serious concern sort of way. The pin is steel, the pulleys are aluminum.. I would imagine there being pulley damage before there is damage to the pin if for whatever reason something happens.

 

not really, I didn’t think about the steel pin would probably bend or mare the aluminum prior to bending or collapsing. Is it possible to “press” or seat them (crank and SC pulley) together prior to mounting so we can assure they line up precisely?

 

Im talking about the 8 holes drilled and what the thickness of metal where they drilled through.

They look like 3/4 inch holes?

 

This looks awesome! Bummer it’s another month or so but great I see one I’m action.

 

I don't know. I didn't think to measure them prior to mounting it on. Lol.

 

Small updates:

I changed out the roll pin out on the NST pulley. The OE dowel pin fits just peachy in there and I am currently running it with no issues whatsoever.



For those not wanting to run their pulleys with the pre-installed supplied roll pins all you need is a small pointed tip chisel and a small hammer. I used the OE dowel to push out the NST supplied pre-installed roll pin and put it in a small bag for later usage (hey you never know).





I took some measurements of the pulley holes @TRON and found that the holes have a diameter of .787" (just a touch over 3/4) or 20mm.



Here you can see the marks at the keyway which the supercharger crank pulley makes on the crank dampner when using the pre-installed supplied roll pin (the OE setup makes the same markings actually). After reinstalling the OE dowel it no longer is a super tight fit due to the fact I filed an ever so slight bit of metal off the crank dampner and I have to reinstall the pulleys in two separate peices on the engine, not really an issue, as once the bolt is in place the setup is still one entire unit.

Moral of the story, if you want to retain and run the OE dowel you will need no additional filing required to do so, if you want to run the NST supplied roll pin as-is, then you will have to file your crank dampner ever so slightly.

 

Thanks @12TRDTacoma I was off by 1 mm for the hole diameters

I’m still curious how thick the aluminum is where those 8 were drilled. But I’m sure I’ll find out later this month if you got it back on already.

So was there any scarring on the stainless steal sleeve? I greased the stainless sleeve part but may grease more if needed when I modify this overdrive pulley

 

Hey one millimeter is very important to her!

Yeah I've got prior scarring on the sleeve because I did not grease it since there were no installation instructions that came with the pulley at the time and I was not aware that grease was needed. This time around I went ahead and did myself a favor and put a nice layer of disc brake bearing Grease all around the sleeve.

 

Any update on this? Wondering if we will see these this month?

 

Yeah, you guys should start seeing these by the end of this month.

 

Anybody hear back regarding their Alt pulley exchange? Sent mine in about a month ago or so, haven't heard anything yet, just been patiently waiting. Kinda assuming the blower pulley and new Alt pulley will be sent out together to everyone..

 

I like your optimism! almost end of feb hopefully soon

 

Any form of update would be nice. @12TRDTacoma had his back in January