Scottish Elises

good morning guys,

I hope all left here are still well its been a while since visiting.

I recently put my supercharger unit in for a rebuild and have had the note back below. should I go for the 3.2 or 3.4? as you guy may know my mechanical nouce is limited.


Can anyone give me guidance on a contact where I could have this remapped?

thanks Tam



"To confirm, the pulley on your supercharger has been re-measured and is actually a 3.3” pulley.
We’ve been looking and a 3.3 has been mentioned but does not seem to be readily available to purchase. The fastest and most common options are the 3.2 & 3.4” versions.
As discussed we contacted CPL for advice on this as we do not know how much the size change will affect horsepower and ECU capabilities. We were told that the difference between pulleys should equate to around 10hp, so with yours being in the middle you’d be looking at maybe 5hp difference. We were advised to go for the larger, the only reason is the horsepower isn’t a huge amount and the current ECU tuning is a complete unknown. That said it was also discussed that the ECU’s should have some flexibility as they have to deal with different air levels/fuel quality etc every day so it is possible it would handle the smaller pulley.

Ideally, if interested in that little bit more power would be to double check if your ECU can be mapped. I would suspect it will be using a common setup that someone can work with. You would also not be looking at major changes so it may not take a great deal of work to double check and tweak.

There is SOS Motorsport in falkirk http://www.sosmotorsport.co.uk/

I haven’t used them but have heard good things
Are you running a KPro ecu? I’d be interested to know how you get on for my Honda Elise

Is the car chargecooled? Most non-chargecooled K20s use a 3.4" nose pulley on the Jackson Racing supercharger.

Chargecooled cars often use smaller pulleys to run the supercharger a bit faster. The chargecooled Link-Up cars typically used a custom 3.3" nose pulley in combination with a slightly larger crank pulley from the K24 engine. I think this gives a supercharger speed which is similar, but a little bit slower than a 3.0" nose pulley with the standard K20 crank pulley.

If you are happy with the existing mapping/set-up, might be worth getting in touch with Maidestone Sportscars (installer of the Link-Up kit) to see if they'll sell you a 3.3" pulley. Alternatively, it might be cheaper to get a 3.3" pulley machined than it would to remap the car - machining down a 3.4" pulley might even be an option.

If you do change the pulley, i'm not sure whether you might also need to change belt length.

Jek