5K Supercharged Sc12 Pulley Modification

[yohan18]

Hey guys I'm doing a 5k supercharged blow through carbie, going into my 82 ke70,

My motor has been built for it. It's got the following

5k block bored out 20thou,

New pistons and rings I think d dished pistons

Reground cam to street setup

Solids conversion

Reground crank

All new bearings,

Welsh plugs,

Seals,

Block was decked and acid washed, honed.

Lightened flywheel

Exedy heavy duty clutch

4k head

Lightly decked

New valves

New valve seals,

New valve springs

3 angle valve grind

 

Extractors and 2 inch straight through pipe with sports muffler with ve ss exhaust tip.

 

I got my sc12 the other day and I took it into work and pulled the pulley off to put a v belt pulley on it. I haven't machined the v pulley yet but i machined the old pulley so I can still keep the geared spline and ill just press the new v pulley onto the machined pulley, I took some photos of the old v pulley machined up.

Edited October 21, 2012 by yohan18

[yohan18]

Pretty much all I did was once I got the old pulley off and apart I just ground the heads off the three pins that held that front part together, punched out the pins and you should be left with the spline, so i then put it into the lathe and turned the outside diameter so it was a clean nominal diameter eg the outside is now 20mm, when I make the new v pulley I will make it .02 interference fit so it won't come apart :), it helps being a fitter and turner.. If anyone needs this done I'm able to machine it for you for a small fee.

 

It's better than welding a pulley on the front of your standard pulley, at least this will run true.

[kickn5k]

You really need to run the bearing for the pulley too. The splined shaft on its own is not anywhere near strong enough to carry the load of a tight belt.

I'm not sure if I have any photos of my pulley on my laptop, but I'll find the for sale thread later this arvo when I get to my laptop. It has some pulley photos on it.

 

Reason for edit.

Hang on it looks a bit different to my sc12 snout. You may be ok. I'll still get that link for you.

Edited October 21, 2012 by kickn5k

[yohan18]

I'm gonna be running a idler pulley aswell so I shouldnt need that much tension as you would with out. The shaft is pretty soft but I think it should be fine. We shall see when I get it assembled.

I can always take it apart and put stronger bearings in it or if needed make a stronger shaft but that shouldbnt be necessary. I hope.

But I would like to see the photos of how you have done yours

[yohan18]

Hey guys I've machined thebv pulley for my sc12, I dunno if its the right size. I found a pulley size to psi calculator and it said my pulley had to be 2.5 inches in diameter, I dunno how true it is but I can always modify it if need be. If anyone has a v pulley on their 1.6 Ltr and can measure it it would be great,

 

Anyways here's some photos of the pulley machined up.

[Evan G]

any reason you didnt go a multi rib belt or gilmer drive?

[yohan18]

Crank pulley is v type.

[yohan18]

I could easily make it a ribbed or gilmer belt system. I would just have to take the crank pulley off and machine it and make a sleeve to press on with the ribbed or gilmer style belts

 

But you wouldn't happen to kno what size pulley you would need for a 1.6ltr, i followed the sc pulley post on here and it worked out to be 104.9mm outside dia (127 crank pulley\1.21 drive ratio = 104.9) does that sound correct?

[KEI069]

But you wouldn't happen to kno what size pulley you would need for a 1.6ltr, i followed the sc pulley post on here and it worked out to be 104.9mm outside dia (127 crank pulley\1.21 drive ratio = 104.9) does that sound correct?

 

That sounds about right. I run a 1 - 1 drive on my 5k with a sc14 and it runs

8 psi at 6000 rpm

[yohan18]

 

 

That sounds about right. I run a 1 - 1 drive on my 5k with a sc14 and it runs

8 psi at 6000 rpm

 

Ahh ok that helps I guess as I have to make a new pulley I might as well go a 6 pk ribbed belt then.

I wanna run 12 psi though I guess that's why my ratio is 1.21