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Discussion Starter · #1 ·
Im after a reduced pulley, going to get the alta but not sure what size to go for. either the 15% or 17%. What sort of gains will achieve from both? I want the power without having to upgrade the intercooler straight away. would I be able get away with a 17% with stock cooler? My driving style is quite sensible with the odd burst. I dont redline it all the time, only when im in a bad mood. lol.

I know 15% is fine with stock cooler. Is there a major difference in gains on the 17% over the 15%?
 

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Nearly there
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17%!

People advised me a 15% is better than a 17% for everyday use. But since I got it fitted last week I think its fine for driving in traffic!

Plus 17% gives you more power lower down as it spins up the supercharger faster.
 

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Discussion Starter · #4 ·
I was worried about over heating but the weather isnt that hot in the uk compared to some of the guys on here from the states.

I've heard alot of people arguing saying 15% is better and 17% is better. Doesnt the 17% cause probs like overboost which switches off the DCS. How does the car feel with the pulley fiited? is there a big diff?

Whats the powerband like? i noticed in my standard MCS that the power is fully on at bout 4K RPM.
 

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a.k.a. BrainRush
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I have a 15% fitted, the car is definately more lively. I'm still kinda concerned about using anything smaller than a 15% becuse it apparently goes faster than the rated rpm of the charger.I have the occasional heat problems (IAT's over 150 F in SF traffic). but I'm generally cruising at highway speed. one thing to watch out for is that if the inlet air temperature gets too hot, the car pulls the ignition timing, netting less power
 

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To give you an idea, we run a 17% on our 220bhp track car and even with a stock cooler it copes, its fine on the road no problem at all, it just about copes on the track, but an intercooler would sort the track use issue.

We recently ran 20% reduction around the Bedford GT circuit with the GTT intercooler and that stayed nice and cool.
 

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Also I with 18% smaller don't have any problem.
But now I have an W/A intercooler and Aquamist WI. It's very cold almost freezing. :D:D:D
 

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THE STICK
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If sticking with a stock IC I'd say 15% (I ran this on a stock IC and with spirited driving it can get too hot). 17% on the stock IC really starts to struggle even in the english summer and you won't get the best from it on a stock IC. It can be run and the GTT 220 cars are very solid, but in the summer they tend to struggle to deliver good consistent power when used in a spirited manor. A 15% with an M7 or BBR chav hat scoop lip works wonders...both me and MINI Morgan have first hand seen good results to reduced temps and improved recovery times since fitting chav hats. he runs a 17% and I a 15%.

If you upgrade the IC and the spark plugs then a 17% will give you the most bang for buck as is very very usable in the UK. Even the GP IC is good enough to cope with the 15% easily especially if you have a chav hat. I know this from persoal experience....If you went for a 17 then you at least need a GP IC, better if you have a GRS or GTT though. That way you'll get consistant good power even in the summer months and even with spirted driving.

Good luck
 
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hi iam fitting a 17% pulley on mine this wednesday. ive already got the bigger intercooler, air feed, exhaust ect. but iam also fitting bigger injectors.

what is the best sort of remap for the job? or dont i need to remap it?
i would prefer to remap it thow.

cheers tom
 

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Discussion Starter · #12 ·
I heard its pointless remapping the car, only cars that really benifit from a remap are turbo'd cars. The standard map on the MINI is fine with those mods ive heard.
 

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I heard its pointless remapping the car, only cars that really benifit from a remap are turbo'd cars. The standard map on the MINI is fine with those mods ive heard.
Hmmmm in my opinion id only recommend a remap if you change the overall fuelling requirements for the engine. This includes injectors(you wouldnt believe how many get that wrong), big valve head and cam. Most other mods effect boost pressure in some respect so these are accounted for by the ecu. If you change any of the above its either a remap or adjust the fuel pressure accordingly. What a lot of people do is chuck in larger injectors and say..."yeah it runs fine...." which I have to disagree. It runs is my answer, but fine? No you have just increase the fuel delivery at all rpms when you are out of closed loop fueling so very rich all the time. Its not cause you increase the power that is draining your tank lol!
 

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We offer the 15% pulley, and recommend the software upgrade too.

The timing and fuelling is adjusted in the software so the ECU is not having to pull timing correction when driving hard. It also irons out flat spots
 
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