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Discussion Starter · #1 · (Edited)
anyone on here with a blown 540i have plots of a dyno run with the boost? Looking to see if mine is ok before going through with another leak test. I am hitting about 5psi at 5k in 3rd gear...I have a 3.33" pulley and a 5.45" on the crank...also have headers so that would reduce. Without headers I would expect around 9psi with headers I am think would see a few psi of boost loss. haven't had her on the dyno yet though. The tune is still now 100% and don't want to go WOT yet just wanted to see what the gurus think this boost level at 5k is like...I was going to run a leak test but decided to do this test first as it is more fun and I am thinking with this result I probably don't need a leak test.
 

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anyone on here with a blown 540i have plots of a dyno run with the boost? Looking to see if mine is ok before going through with another leak test. I am hitting about 5psi at 5k in 3rd gear...I have a 3.33" pulley and a 5.45" on the crank...also have headers so that would reduce. Without headers I would expect around 9psi with headers I am think would see a few psi of boost loss. haven't had her on the dyno yet though. The tune is still now 100% and don't want to go WOT yet just wanted to see what the gurus think this boost level at 5k is like...I was going to run a leak test but decided to do this test first as it is more fun and I am thinking with this result I probably don't need a leak test.
This is off topic but I wanted to get an idea of what an SC'd 540i feels like. Can you describe the response, the power/torque curve, the noise etc.
 

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Discussion Starter · #3 · (Edited)
This is off topic but I wanted to get an idea of what an SC'd 540i feels like. Can you describe the response, the power/torque curve, the noise etc.
There is no sensation of lag...response and power are immediate even when not "boosting". Off line speed and power is great...they are still big heavy cars so it is not over the top (of you could remove like 700lbs it would be like a purebred). Once moving is where they shine. Acceleration on highway is unbelievable. It will throw you back in the seat at 80, 90 even 100 mph! As SC power is immediate as you step down it goes no lag time. I had the car full with 5 adults the other day and it was still far faster on the highway than it ever was naturally aspirated with just me!

On another note I hooked up my leak tester infront of the SC. Found some leaks in a surprisingly easy way. I have a plumbing coupler I made with a PVC cap and a barb fitting on this. I attached a hose and an air compressor fitting on the other side. Set my compressor to 10psi. When she got to 5psi leaks were evident. They were leaking at the silicon coupler and produced a loud whistle as it vibrated the silicon like a woodwind instrument reed...tightened one and another came about at a slightly higher pressure. Worked my way through the intake until it stopped screaming and pressure went to about 11psi. I have never had intake leaks be so easy to find and fix than with this noise haha I was all ready to use the soapy water method to find them but this was far better.
 

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anyone on here with a blown 540i have plots of a dyno run with the boost? Looking to see if mine is ok before going through with another leak test. I am hitting about 5psi at 5k in 3rd gear...I have a 3.33" pulley and a 5.45" on the crank...also have headers so that would reduce. Without headers I would expect around 9psi with headers I am think would see a few psi of boost loss. haven't had her on the dyno yet though. The tune is still now 100% and don't want to go WOT yet just wanted to see what the gurus think this boost level at 5k is like...I was going to run a leak test but decided to do this test first as it is more fun and I am thinking with this result I probably don't need a leak test.
I also pressure test my intake and I have found many leaks.

Here is an old dyno that may help you.
http://forums.bimmerforums.com/forum/showpost.php?p=10777483&postcount=57
 

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Discussion Starter · #6 ·

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Thanks for the dyno! I am wandering if anyone has plots of manifold/boost pressure with that. You are running 91? Have you tried 93? It looks like you may have knock at like 5700rpm. Good power if you can get rid of that I bet you would put down 410-420
91 is the best i can find out here. I am interested in your observation. How would I go about getting rid of that knock?

And that is a lot more power than dinan advertises wow. They claim 412 and you are at like 488 haha nice
Actually my car was a prototype and is running more boost than their final product.
 

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Discussion Starter · #8 ·
91 is the best i can find out here. I am interested in your observation. How would I go about getting rid of that knock?

Actually my car was a prototype and is running more boost than their final product.
Things to look at to eliminate knock

1. Intercooler this is the best way but will be most expensive.

2. add water/alcohol injection having it kick in and spray around 5-5.5k.

3. Increase octane of fuel may be hard if you don't have it around but would the cheapest way.

4. Could modify the tune to go slightly richer around that range...this would cost a lot too having to have a custom dyno tune.

It doesn't look that bad on yours at all just wanted to make note of it and totally not insulting your dyno pull at all it is impressive to say the least just trying to help you improve it. My recommendation if you can fund it is put in an IC. Anything over 6psi should probably have IC.
 

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Discussion Starter · #9 · (Edited)
Your AFRs look pretty lean for a Dinan tune also they tend to be a lot more conservative than that haha looks like mid to high 12s under boost. I would image they are usually in the 11s to avoid knocking. This certain helps you with power but you should do something to cool down those charge temps.
 

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Bricas45 thanks for the input. I have been thinking about water injection for some time. Do you think MAF or boost controlled is a better setup? Brand?
 

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There is no sensation of lag...response and power are immediate even when not "boosting". Off line speed and power is great...they are still big heavy cars so it is not over the top (of you could remove like 700lbs it would be like a purebred). Once moving is where they shine. Acceleration on highway is unbelievable. It will throw you back in the seat at 80, 90 even 100 mph! As SC power is immediate as you step down it goes no lag time. I had the car full with 5 adults the other day and it was still far faster on the highway than it ever was naturally aspirated with just me!

On another note I hooked up my leak tester infront of the SC. Found some leaks in a surprisingly easy way. I have a plumbing coupler I made with a PVC cap and a barb fitting on this. I attached a hose and an air compressor fitting on the other side. Set my compressor to 10psi. When she got to 5psi leaks were evident. They were leaking at the silicon coupler and produced a loud whistle as it vibrated the silicon like a woodwind instrument reed...tightened one and another came about at a slightly higher pressure. Worked my way through the intake until it stopped screaming and pressure went to about 11psi. I have never had intake leaks be so easy to find and fix than with this noise haha I was all ready to use the soapy water method to find them but this was far better.
What about the noise? Any idle noise from the supercharger and any sound while driving? By the way how much weight would you say the kit added?
 

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Discussion Starter · #12 ·
I would use boost based on mine cause I hate the MAFs on these cars they are prone to fail and I would trust the injection more on boost inputs that way if you MAF fails for some reason it would still work.
 

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Discussion Starter · #13 ·
What about the noise? Any idle noise from the supercharger and any sound while driving? By the way how much weight would you say the kit added?
I doubt the kit adds anything substantial. You remove parts and add others, but I haven't a clue the net. I am sure there is a net gain but probably not substantial.

The noise has that distinctive whine at idle. I have the vortech SQ (super quiet) model and it isn't really loud at all especially with hood shut. I don't hear it much while driving however due to my exhaust being loud. When I drive past objects I can hear the SC echo back at me. I like the sound of the SC personally.
 

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By the way how much weight would you say the kit added?
probably 30lbs, but that's just my opinion from holding the supercharger it self and carrying the boxes in the house....
 

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I really want to SC my car, it'll be cheaper and more straight forward but I need the autobox. I love 6 spds but I just can't do it again in traffic everyday. My concern is that the autobox will self destruct or the engine itself. Did you guys rebuild your motors with forged internals and what not or is it actually truly plug and play.
 

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Discussion Starter · #20 ·
I really want to SC my car, it'll be cheaper and more straight forward but I need the autobox. I love 6 spds but I just can't do it again in traffic everyday. My concern is that the autobox will self destruct or the engine itself. Did you guys rebuild your motors with forged internals and what not or is it actually truly plug and play.
My engine is a rebuild to factory spec no forged internals. If I were to add anymore boost I would rebuild with forged internals. If you stay under 9psi you would be fine with stock internals. Anything over 6psi add an intercooler. They're plug and play if you get a kit. I would recommend upping boost on a kit set up though as none of them come with an IC.
 
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