Andy im just waiting on a clear day, or dyno to open up which ever first.....

Maxmini, Ive been really busy, havent forgotten about those guys, unfortunaty some other things have a ittle more priority, i will be working on some pictures this week, but it is still a busy week......

 

>>First i want to touch a topic that you quoted from..."When the heat goes up this summer and people are putting 18 lbs of boost on these engines, I think we will see problems. Even Randy doesn't recommend these. " one Randy is not God, a very knowledgeable guy and not trying to knock him, so therefore he shouldnt be mentioned(but i feel he is wrong on the 19%, and funny that he is in a less harsh enviroment, that would make the 19% less stressfull on the engine due to altitude and heat, and less humidity)...two i and many others have been running 19% in the heat of summer with no problems, look at my post as well as BMP/Promini's website to see. I feel that I am probably in one of the worst area's as far heat(not saying im the worst, but close) Im at sea level(densest air) Southern Heat, 95+ degrees day on the regular, on the coast(100% humidity or close to on a reguar basis) now i have not had a single problem yet, 20,000 plus miles hard driven with the 19% pulley, I have done many install for people in FLA and AL, more heat than here still not a problem, but if you read this thread in its entirety(?) i and andy have discussed the heat issue, the heat is more important with these levels of boost, than the pressure increase due to heat, not saying that the pressure is not important, but the pressure due to the warmer ambient temp is a smaller factor, than the pressure created by compression and boost, a warmer ambient temmperature will cause the intake charge to be much less dense, there for in the end causing LESS cylinder pressure than a cold charge, hence the purpose of cold air intakes and intercoolers, also an explination on why i can hit boost levels of 25PSI in the cold winter(sub 30d here), and only 19-20PSI in dead heat of summer, with hot air you will lose power. The formulas i have used in this thread explain all this, all my calculations are based on a 90d "standard" day,( im still wondering who created and why 90d is standerd, but it is) which for most is a rather hot day.. Hope this helps!!


Not sure what you are really stating here, but
1) I never said Randy was a god.
2)20,000 miles on a pulley does not indicate any form of reliability. It is a spit in the bucket. I don't doubt the pulley will survive 20,000 or even 50,000 miles of hard driving.
3)A lot of people are installing these items with the ECU chips that raise the redline to 7,200 rpm. They are then running the engine up to this rpm and exceeding the rpm of the supercharger. This is going to cause problems for people who are unaware of this and just blindly putting these pulleys on.
4)Why is everyone stopping at 19%, lets all go to 25%. We can then even get the boost higher at a lower rpm range.

I am not stating that the pulley doesn't have some neat benefits, but I don't think it will be shown to be as reliable as the 15% pulley. Obviously neither you or me can indicate if it really will. Neither of us have done extreme testing on these to see if they will fail. I think 20,000 miles on a product cannot be a basis of saying the product is fully reliable. At this point only time will tell. There is no doubt that the stress on the engine is increased with a 19% pulley and that increased stress on an engine will cause it to fail quicker.

 

>>But now you put the intercooler, i will use an approximate for the stock of 85% effecientcy because that is very easily attained....
mind you...
>>
>>now on a larger air to air or water to air inter cooler you should be able to get 95-98% effecientcy so.....

I highly doubt the stock intercooler is 85% efficient. Most stock intercoolers are in teh 60-70% range, and we all know the Mini's intercooler is not very efficient (heat soak is a problem)

I also highly doubt you can get any type of intercooler to 95% efficiency, let along 98%.

What is a 90d day? What does the d stand for? It is some kind of temperature measurement? You have used it, indicating it was a hot day, so I am assuming it is some form of measurement, but I have never heard of it.

 

>>Yes i do appreciate that, do you have any thoughts on the dip at arounf 300cfm or 6000rpm? depending on which way you want to look at it.......As i stated in the other thread, there are many air restrictions in the air path, throttle body being one, now the more you try gain in boost requires more air, so the effects of poor air path become more amplified, I feel the graphs your showing, are probably correct and that the dip at 300cfm is due to air restriction, because up to that the 17% is pulling more air, after it almost the same, i do not know where you are measuring the air flow from to speculate which of the air restrictions that i have found could be causing this.. what is your impression of the dip?


There is a drop in cfm at 6,000 rpm because Andy's assumptions were a drop in efficiency from 100% to 95% at 6,000 rpm. The efficiency rating was in the numerator for his cfm calculations therefore the caculated result showed a drop.

 

>>I'm not gonna plug in your 19% figures until I see actual data. I wish I had been able to log temp on BlueMCS's car ... ah well. Maybe I'll swap on my 19% tomorrow. It sure makes metric calculations simple when you do logging at sea level and 0 C.

Hey Andy,

I have about 10h of 19% pulley data which include boost and IAT readings from the OBD2 logger.

Are you interested in this data?

Kev

 

as far as pulley percentages greater than 19%, there is a physical minimum diameter limit beyond about 22% for anything with bolts. Conceivably, one could make an even smaller, single piece press on, but the belt wrap would be very tight. If some adventurer wanted to get more, he would have to increase the crank pulley diameter at the expense of also speeding up the alternator and AC pump.

 

BlueMCS wrote:

Yes, please email it to me. Thanks.


M3NTAL_Kev wrote:

Yes, please email it to me. Thanks.