huh...that sucks.

why would you have to bend it.

i would think that you could at least do a lil work and gett he pulley off with ease.


ive got another question.....can you change the pulley on a JCW kit or no?

 

I don't understand why it would bend, but it did slightly. You can upgrade a jcw pulley yes.

 

This is incorrect. Helix does sell the stock sized pulley. But you're right, you can't put the original one you took off back on.

 

With the 19 you need a new belt right?

 

Yes.

 

Is there anyway to buy a John Cooper pulley and your warranty still be intacked? If so where can you buy one? If not which one is the best (Mini-Madness, Alta...etc.)

Thnx.

ZM

 

They will only warrenty the car if you install the whole kit. At least that is what i was told by my dealer. Mine is from Helix MiniSports, and is fantastic.

 

Then it would not be incorrect, you might be able to put a stock SIZED pulley back on, but the dealer would know it is not stock and thus know you changed your pulley size at some point.

 

Does anyone have any experience with what is likely to be necessary if the 19 percent pulley causes a failure? What is likely to fail? What is it likely to cost in parts and labor?

It does not seem like it is the supercharger.

Head?

Block?

Cat?

Dog? Just testing.


Vince

 

I might consider a change from my current 15% pulley to a 19%, but right now I'm thinking that what I would do instead is replace the existing intercooler with either the larger Alta or the soon-to-be released RDR air-to-air unit, and keep the 15% pulley.

My logic is that the larger intercooler will provide increased performance (even with the 15% pulley) over a wide range of temperatures, including hot Texas summer days. In addition to the increased performance, the lower IAT should keep the engine happier longer, and the lower RPMs with the 15% pulley should likewise help the supercharger and water pump live longer lives than they might if driven with a 19% pulley.

Hehe... then after I get the bigger intercooler, the temptation of a 19% pulley might just be too much.

Dan

 

I ordered the 17% from Helix to replace the 15% i alredy have installed. If I trusted myself i would have gotten the 19% but I don't. So just in case I do take my RPMs high, 6500-7000 I know I won't cause that much damage.

 

When you install the 19% reduction pulley you must be sure you are willing to accept a calculated risk that something/anything could go wrong with your engine which includes anything other than a direct effect of the pulley being installed. This is known as bad outcome.

If you have a supercharger that goes bad in a stock MCS then the repair or replacement is covered under warranty. If your car is new and has a part that is about to fail but you install the mod on it before it fails and then it fails is it the mod that made it fail or was it going to fail anyway? You won't be able to tell.

So far of the 19% pulleys installed by Helix13.com none of them has had a problem. You and NAM members will be the first to know if and when that happens. It is a calculated risk and we feel that enough data is in that we feel the 19% is reliable.

So-
"It does not seem like it is the supercharger."- well anything can go bad with the supercharger before you install the pulley so be aware. Over time maybe a supercharger vain could wear but we have not seen anything significant from the 19% pulley.

Head? Nope.

Block? Nope.

Cat? Only a racing cat if you have the Milltek header.

Dog? Just testing. Nope. Just the cat and the cat-back exhaust.

Cavitation has not been reported by any MCS with 19%. You can rev up to redline but just be careful.

If nothing fails then there is $0 for parts and $0 for labor.

Now directly a result of the 19% pulley you need to replace the smaller belt (about $25) every 25,000 miles so that is ongoing and you need to pay for alot of gas so you can enjoy your speedy MINI. Figure about $170 for about 75 gallons (2000 extra miles of fun per year) at about $2.25 per gallon. Or you can calculate $.25 per mile. It's still better than going to Las Vegas.

 

I'm going to have to disagree with your assement of what COULD fail at higher boost levels. Note that I am not saying that there WILL be any failures. I should also comment that I am currently using a 19% pulley from Helix and I have no plans to replace it since it does exactly what I wanted.


Smaller pulley = more boost at any given engine speed
More boost = more cylinder pressure (peak cylinder pressure is not necessarily at redline)

More cylinder pressure = lots of different potential failure modes depending on design margins (currently unknown outside BMW)

The list would theoretically include the power cylinder kit (piston, rings, connecting rods, crankshaft, main and rod bearings and piston pin bushings), block, head, head gasket, seals (crankshaft seals and any others with air connection to the crankcase or intake plumbing). Higher cylinder pressures also drive higher vibration levels, which potentially fail any of the accessory mount points or housing on the engine. Increasing water pump speed potentially leads to failed water pump seals, increased errosion in the cooling system passages (aluminum only, cast iron will be fine) and radiator, and cavitation. Cavitation will most likely occur at redline first, but is also very much related to coolant temperature and system pressure so just reving the engine up won't tell you anything. If the water pump cavitates, that decreases cooling system pressure and allows localized boiling in the hotter areas (probably in the cylinder head passages first).

Some of these failure modes don't necessarily happen quickly, while others will.

Keep in mind that I'm NOT saying that any of these areas will be problems. I'm just making a more accurate list of the potential failed components as a result of higher boost. I have no idea what boost level is the threshold for our engine's weakest link, nor what that link is. To say that neither the block nor the head will fail due to spinning the supercharge faster is not really true or known at this point. I've decided to take that chance myself, but I'm really just gambling that the design margins in the engine will tolerate the increased pressures. My daily driving duty cycle is incredibly easy on the engine (low to middle rpms, fairly gentle acceleration, rural highways and 45 miles each way), but during autocrosses I have no problem going to redline(stock rev limiter), nor do I worry about it.

For what it's worth, endurance / abuse testing engines is what I do for a living.