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Discussion Starter #1
Today i've managed to find time to put on my RPI pulley. Just been out in the car- that is incredible!! Revs faster, much less hesitant on throttle, seriously seriously impressed! Money well spent, so thanks to all on here for the recommendations.

Did the RPI scoops, with AFE drop in filters, rather than the BMC, early last week and did feel some improvement at speed. I guess the pulleys feel more dramatic being lower down, and noticeable on acceleration from a standing start.

Had the can dyno'd yesterday, to get a baseline before the bigger mods, and got a top run of 446.52 at the wheels. That was with just the air filters, and scoops.

Time for more mods!!!!
 
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that is a good number for baseline. what gear is that in?
 

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Discussion Starter #3
In 4th gear buddy, as I am yet to have the limited removed. Here is the graph taken from the 4 runs. It was on dyno dynamics, which seems to read high anyhow. This graph is with DIN correction, using SAE correction the highest run was 434.28 whp.
 

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Hi James
Good figures. Pulley is a good cheap mod. Are those figures on a p400'run or p500 sports? Are you goin to pull the trigger on the exhaust?
 

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Discussion Starter #5
That was in P500 Sport mate, but without the pulleys. Just scoops and filters fitted at that point.

On the exhaust, I reckon so. It's a good price for a full exhaust and I need some more sound from the beast!! If it does some more power that would be good also. What you thinking?
 

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That was in P500 Sport mate, but without the pulleys. Just scoops and filters fitted at that point.

On the exhaust, I reckon so. It's a good price for a full exhaust and I need some more sound from the beast!! If it does some more power that would be good also. What you thinking?
Not sure as I've had bad feedback on it by someone,
 

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hope to hear soon about your pulley result, can't wait to to recieve my moods, i had perchased the RPI Pulley and RPI scoops with Bmc filter and my lovely EISENMANN race exhaust with oval tips, i am hungry to get these bad *** parts as starting . love My new 2010 E63 M6........
 

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Discussion Starter #8
Good choices! I've got an eisenmann race on the way, due for delivery next week. Congrats on your new purchase!
 

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So what does the pulley do ?? Where do ya get one ?? I'll assume it under drives all the accessories which reduces drag. Why wouldn't the German engineers have figured this out ?? Jon :) I have yet to find a mod so simple and inexpensive that produces results as the charcoal filter delete did !!
 

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well my friend you have 2 choices RPI and EVOSPORT, this pulley is a replacement of the crank pulley, it is lighter wight and it makes all accessories run Little faster which will perform better specially the water pump pulley which will make your V10 colder in hot weather, it is a logic thing, this is my opinion, i had tried it in my old M5 E39 and it works well, it is a mater of torque more then HP. correct me if I'm wrong boarders.
 

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Discussion Starter #11
M5leader it is lighter weight you are correct, but the major benefit to the pulley mod is the size of the pulley. It is smaller,I think its about 85% of the OEM if I remember correctly, so it reduces parasitic drag from the crank to run services. This is to the tune of 15% approx.

On the pulley side it only runs AC and Alternator, no significant mechanical engine elements such as oil or water pumps, therefore it would be pretty safe to say that no major damage can be caused by using a pulley. I don't recall reading any times either when it was unable to provide enough power to run the services well enough in standard form. I certainly haven't noticed anything.

Jonny in response to why the German engineers didnt figure this out, I guess they did, but as a manufacturer they make compromises between all of the elements to provide a one size fits all car. All we are doing with the pulley mod is changing the priorities. From providing the alternator and the AC unit with less belt drive we reduce the parasitic use of engine power, thus increasing performance.
 
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well my friend you have 2 choices RPI and EVOSPORT, this pulley is a replacement of the crank pulley, it is lighter wight and it makes all accessories run Little faster which will perform better specially the water pump pulley which will make your V10 colder in hot weather, it is a logic thing, this is my opinion, i had tried it in my old M5 E39 and it works well, it is a mater of torque more then HP. correct me if I'm wrong boarders.
Under drive pulleys have a smaller diameter which turns the accessories slower. That (not lighter pulley weight per se) is where the reductions of parasitic power loss come from. In fact, your A/C will be less cold (at the extreme) with an under drive pulley as the compressor spins slower compared to when driven by a stock pulley.

Cheers

EDIT: Oops - I see reesy_csl already answered this...
 

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In 4th gear buddy, as I am yet to have the limited removed. Here is the graph taken from the 4 runs. It was on dyno dynamics, which seems to read high anyhow. This graph is with DIN correction, using SAE correction the highest run was 434.28 whp.
It's a dynojet dyno.

SAE corrections are what most people will use here, no DIN.

Your SAE readings are in the correct region for a V10 running in 4th gear on this dyno for a stock car.

Can you post the graph showing the correction factor? Do you have the DRF files?
 

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Discussion Starter #14
That's good i'm glad to hear that! That was a pretty stock run, just drop in filters and scoops. The chap at the dyno had done another M5 a couple of months before that had done a similar figure. I've attached my DRF in a zip file, can't attach any other way, and a corrected graph from WinPEP
 

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RPi mods

Your baseline is good as I started with 442 to the rear. After the mods from RPi I got 495 to the rear. If you want to check out the video which shows a short segment on the dyno and all the mods done by RPi, click on this link.
YouTube - BMW M6 by RPI: M6BOARD.com

And I am stoked on what the mods have done to the performance.
 

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Discussion Starter #17
Definitely! Feels like a different car. Is that yours on the youtube video then?

I've watched that video a fair few times before!! Addictive!
 

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Definitely! Feels like a different car. Is that yours on the youtube video then?

I've watched that video a fair few times before!! Addictive!
Yes that is my car and I was the driver and my son the video guy and editor. It was a fun first time project and we have plans on doing another one with other M cars involved. Yes, my M does feel like a different car with the KWs, and RPi mods. Enjoy your mods and remember don't let your women know who is really number one.
 

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Discussion Starter #19
Yes that is my car and I was the driver and my son the video guy and editor. It was a fun first time project and we have plans on doing another one with other M cars involved. Yes, my M does feel like a different car with the KWs, and RPi mods. Enjoy your mods and remember don't let your women know who is really number one.
Well done on the vid, your son did a great job on that. Looking forward to another installment! I'll take your advice on that one - 'remember don't let your women know who is really number one'. Cheers!
 
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