Mini supercharger on 1zz

[Carolyn]

just remembered:  Making the pulley and machining the key slot in the supercharger driveshaft....  That's a job most will have to pay a machine shop to do.

One we know the correct (ideal) pulley size) the pulley machining can be set up for CNC and be quite reproducible.   The drive shaft has to be pressed out of the housing for machining and pressed back in.  For us (our own machine shop and tame master machinist) this was not a big issue.  For others it is an added expense.

There's quite a lot of welding to do, the exhaust, the output duct and the mounting brackets.  Most folk would have to outsource that, though cutting and shaping the parts ready for welding is not too hard.

[Blue al]

So pleased to hear you have this in the can
I know this is the route you took,
 but for anyone following in your footsteps
 supercharger pullies are a simple clamp on part, via my mini specialist, no machine shop required, just need to confirm final diameter that suits the application best on he road

[Carolyn]

Not in the size I needed.  If you look back through the thread (there's a lot of it!), you'll see this was investigated.  Believe me, we didn't want to have to make pulleys.

[Blue al]

Not in the size I needed.  If you look back through the thread (there's a lot of it!), you'll see this was investigated.  Believe me, we didn't want to have to make pulleys.

Apologies if I missed that point

These are only the "off the shelf" dims that suit the mini as a double check, look at bottom of this page
 m http://www.kavsmotorsport.com/mini-tuni ... ger-tuning m

Custom sizes can be made, that will suit the 2 part clamp system,
gives some onward flexibility should you wish to fiddle with the boost
For example One was changed on my car at the side of the track at santpod

[Carolyn]

Yep - we looked at that source, amongst others and actually found bigger ones than they offer - but not big enough.

As we can make our own, it made no sense to special order one.  We went for the key method because we could make pulleys ourselves.  Just as easy to change...  All about budget in the end.

[lamcote]

The actual boost produced by a supercharger depends on the efficiency of the inlet tract so to calculate likely boost pressures with different pulley sizes I really need an accurate measurement of the boost in the plenum chamber you are getting with the 105mm pulley. I could then calculate what difference a different pulley size would be likely to make.
Without the current boost I would have to estimate that efficiency number and that inevitably leads to inaccurate results.

[Carolyn]

The actual boost produced by a supercharger depends on the efficiency of the inlet tract so to calculate likely boost pressures with different pulley sizes I really need an accurate measurement of the boost in the plenum chamber you are getting with the 105mm pulley. I could then calculate what difference a different pulley size would be likely to make.
Without the current boost I would have to estimate that efficiency number and that inevitably leads to inaccurate results.

Point taken, Patrick.  I'm after a 'theoretical' number - not an 'accurate' one.  If you calculate on the basis you used before to arrive at a possible 120 mm pulley, what boost would 105 mm give?  I don't expect the answer to be accurate..   It's an 'all things being equal' request.  I don't expect we'll get as high as the number you come up with, just a 'maximum possible'.

I'm trying to avoid putting it under load with a bunch more boost than I think I've got.  If I know what is the most a 105 mm pulley will give, I can load her up with a safe setting.

[lamcote]

Based on the previous calculation for 120mm but modified for 105mm

1.6l is 0.88888 of 1.8l
138.7/65.5 = 2.12 and 135/105 = 1.285
1.285/2.12 = 0.606
10.5psi * 0.888 * 0.606 = 5.6psi
Assume our layout is 15% less efficient than the OEM Mini
5.6 * .85 = 4.7psi

However, this was always intended to be a safe starting point, so I think this actually overestimates the potential boost because I am not convinced that the impact of the changed pulley diameter is really a straight line, so the max boost achievable may well be less than 4.7psi calculated above, so the 105mm pulley should be safe.

To achieve the 6-8 psi you want it may need a smaller pulley again, maybe even the standard 65.5? Things will be much clearer when we get a boost measurement.

[Carolyn]

Cheers Patrick.. That's just what I was after.  5.6 psi would be brill.  I do have a smaller pulley lined up, just in case.

[Essex2Visuvesi]

Not sure if you chaps have seen this
 m http://autoapps.eaton.com/Simulator/ m
might help with you calculations for pulley sizes

[Carolyn]

Not sure if you chaps have seen this
 m http://autoapps.eaton.com/Simulator/ m
might help with you calculations for pulley sizes

Thanks for that.  Had a go with it, but it was so slow, I lost the will to live and had to lie down....

[lamcote]

Any updates on how this has turned out?

Thanks

[Carolyn]

An update.  I've just put a rebuilt engine in the car and built the systems back up.  I thought I'd get a pic before it's all obscured by the exhaust.  Gives folk a chance to see the layout.

[The Other Stu]

Is it still running rich?

[Carolyn]

Who knows?  Haven't started it yet.  Small matter of putting the exhaust on.  Got standard injectors in for now, so it should be fine.  I think all the nasty black stuff was the result of a buggered engine.

[shnazzle]

What's the gubbins on the left in the alloy thing? Are you hiding an air filter in there?

[Carolyn]

That's the original airbox.  Turned through 90 degrees and upside down.  The alloy is heat shielding.

[shnazzle]

Clever  sdick dick sdick y

[Carolyn]

I so want to know what got censored?

[Joesson]

Clever indeed.
I tried to emulate "censored" and "y" without success!

To use an old expression, maybe it' s Double Dutch  s:wink: :wink: s:wink:

[Carolyn]

Double Dutch?  Ah that would be Mr. Den Ousten and Mr. Vanzyl?

[MrT]

Carolynne
Do you have an aerial photo of the layout please? and one of the exhaust manifold off the car?
Thanks


cheers

Tyler

[shnazzle]

Double Dutch?  Ah that would be Mr. Den Ousten and Mr. Vanzyl?

Nah. John's a fake Dutchy. Pretender. Name isn't even written correctly  s:) s:)  Once he starts introducing himself as Jan van Zijl, we can talk hehehe

I so want to know what got censored?

I didn't see the censorship haha! Must have that setting off

[jvanzyl]

That's John François Le Grange van Zyl to you mister!  s;-) ;-) s;-)  can't get the umlaut on the y on this keypad..

Sent from my Moto G (5) using Tapatalk

[Carolyn]

Herewith the manifold.  Picture from up top, later...