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      08-16-2012, 01:14 AM   #1
radiantm3
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Drives: >1000 HP in my garage
Join Date: Sep 2008
Location: Danville, CA

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2011 E92 M3  [4.80]
2013 BMW X5M  [4.33]
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Tracking the M3 with ESS 535 Supercharger in 100+ degree weather (video)

So before I go any further, I want to point out that this post isn't intended to make anyone look bad or be biased. I'm just posting whatever facts I have. I had the ESS 535 kit installed on my car a few weeks ago and having been loving every moment of it. I won't go into details about how good it is because that's already been done many times. I just want to post what I thought was a very interesting result after my day at the track with the kit.

About a month ago I was at Thunderhill Raceway. Weather was somewhere in the low to mid 90's and my best lap of the day was a 2:11.7. This was before I had the supercharger and I had my 18" track wheels with Pilot Sport Cups.

Yesterday I returned to Thunderhill with my recently installed vt535 kit. I was pretty slow all morning (probably because I witnessed a Porsche GT3 spin into a wall in the first session and point-by passing in my group), running anywhere from 2:15 to 2:18. Temps were in the high 80's to low 90's and I was running my cup tires. Halfway through the day I noticed my left front tire starting to cord on the outside. Lesson learned: 1.8 degrees of negative camber is not enough to run competition tires. So I switch back to my 19" street wheels that have Pilot Super Sports on them. Strangely enough my times start to get faster. But the reason for that is proof that it's not a good idea for a novice driver to run DOT competition tires or slicks. My Cup tires never made much noise so I was always afraid to test the limits of the tire. I've posted a few videos of going quite sideways with these tires and it happens very quickly. With the super sports, I had plenty of audible feedback to help me sense how much grip I had and how much more I could push them. So the day was getting hotter and I was running faster times with worse tires and bigger/heavier wheels. Lets just say I'll be putting AD08's on my track wheels before my next event. I feel way more confident with street tires and can find the limits better.

Anyways, back to the supercharger. So while on the track, I didn't really get a sense that I was getting robbed of so much power by the heat. I was pulling harder on a bunch of cars than I have in the past without the kit. But my times were worse than before the kit. So I was thinking I must be screwing up pretty bad in some of the corners (at least much worse than my last time out). But when I went home and got the video and data together, I noticed something interesting. Cornering speeds were a bit higher with the Cup tires (though not as fast as they could be), but acceleration on the straights were pretty similar between the videos. So what is the reason for this? Does 5-10 degrees of heat make that much of a difference in performance? Are non-intercooled supercharger kits just useless in 100 degree weather? I know there's not enough data to come to any real conclusion, but I thought it was worth sharing my experience and a video comparison between the 2 days. My car is pulling very strong back home in 80-85 degree weather. I should also note that my car ran great all day. Engine temps were about the same between the 2 days (with and without the supercharger). I do remember my car stalling once yesterday after I started it. It sounded like it was gasping for air for a couple seconds and then died. I started it back up, gave it a bit of gas and then it was fine.

I plan on dynoing my car sometime in the next month and will be at Laguna Seca for 3 days in about a month as well. Air temps will be a lot cooler there and so I really hope to see this kit shine.

Also, I just realized that I can probably pull temperature data from my logged Solo DL files. I'll try to find those and post them sometime. Is there anything else worth trying to pull from my logged ECU data while I'm at it?



After watching the clip a few times over and over I noticed a few things:

1) First clip is about .5 seconds ahead of the 2nd. I should have matched the timer in post. :\
2) I'm using a lot more throttle in the first clip. I'm not sure if that's because of more grip, less power (no blower), or both?

But on the 2 long straight aways towards the end of the video, you'd expect the clip on the right to hit a much higher speed before braking. That's what puzzles me. And it feels like the RPM's are climbing very slowly on the final straight in the video on the right.

Update:

Here's some temperature data from my Solo.

1 Month ago without the supercharger:



- Laps 1-3 were warm up laps
- Didn't get a final cool down lap

Yesterday with the 535 kit:



- Lap 1 was warm up, lap 3 was cool down

Few things to note:

- Temps are in Celsius
- Water temps could be way off because my coolant temperature sensor is going bad. Got a code for that about a week ago and waiting for the dealer to get the replacement part in.
- Probably not relevant, but I should note that I had RPI scoops up until the supercharger install. They do block a little bit of air flow to the cooling fan.

Last edited by radiantm3; 08-16-2012 at 12:17 PM.