P2 Supercharger Thread

boe said:
Excited for you rbb. How/where are you sourcing your drive pulley?
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You ask tricky questions :)

My next step is learn all I can about batteries and motors. I have been unable to get a response from the manufacturer regarding a compressor map so my default gearing/pully sizes is going to be a guess followed by some trial and error. Also I am not liking how only half the mounting points are used to hold the compressor onto the backing plate. So I think I'll drill some holes and add 4 more bolts to it.

Then finding a location for it in the engine bay will be a fun curse filled day I imagine :ROFLMAO:
 
I did some digging, and asked a couple of AI bots, chatgpt and googles gemini, they seem to agree that turning the compressor at 35,000rpm, a PR of 1.5, 65% efficiency and 65ish pounds of air will take 37 to 40 kilowatt's of power (50+ hp)

Does that sound right to you guys?
 
I put some info into Matchbot and tried to find a similar compressor map and it gives shaft HP as an output.

Matchbot

www.borgwarner.com www.borgwarner.com
No idea how that translates to our application but I fugured its a reasonable start. i think i was looking at <20HP for a pressure ratio of 1.2 so not far off your numbers.
 
yea, so I am thinking a dual motor setup to drive the compressor, high rpm and stepping it down through the belt drive. Maybe have the motors drive a shaft that is 1:1 with the compressor and drives the belt, gear the motors to the shaft, flip the motors 180 deg to the other and have each motor drive a different end of the shaft to try and reduce the package size
 
NickM said:
I put some info into Matchbot and tried to find a similar compressor map and it gives shaft HP as an output.

Matchbot

www.borgwarner.com www.borgwarner.com
No idea how that translates to our application but I fugured its a reasonable start. i think i was looking at <20HP for a pressure ratio of 1.2 so not far off your numbers.
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Look at the map, locate the value on the left and determine the units. If it is in meters per second (m/s) you can use the following calculator to convert that in to rpm. I've been using this bot for years, initially for traditionally boosted applications but now for trying to identify the best size turbo compressor assembly to suit the range of performance I want for an electric turbo.

M/S To Rpm Calculator - Calculator Academy

Enter the linear speed in meters per second and the diameter in meters into the calculator to convert linear speed to revolutions per minute (RPM).
calculator.academy calculator.academy


BW MAP.jpg
 
AlexLTDLX said:
The P2 is basically a Vortech Si trim. View attachment 812
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yea, I had tried to get the manufacturer of the P2 to provide one, but I tried several methods of communication with nothing but silence from them.

I know nothing about compressor design, but I suspect the even if the volute interior is the same and of the same quality of finish that the impeller design would make a big difference. So I am assuming the P2 is a Chinese copy and probably has a lower standard of finishing, and possibly just what ever impeller they could find that fits. That is not to say I am suggesting the quality is bad, more along the lines of 'you get what you pay for'.

But I am not aiming for the moon so I reckon it will be all good in the end.
 
Miikka1 said:
Hey! I have this speedmaster p2 unit. Do you guys think this sounds normal?
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I don't own one but I'm familiar with what bad and or cheap bearings sound like and that one sounds like it could use a bearing upgrade. I read recently on the forum where someone upgraded to ceramic bearings which I'm sure will sound drastically better than that if they make a sound at all.
 
maticulus said:
I don't own one but I'm familiar with what bad and or cheap bearings sound like and that one sounds like it could use a bearing upgrade. I read recently on the forum where someone upgraded to ceramic bearings which I'm sure will sound drastically better than that if they make a sound at all.
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Yeah, seems like the bearing next to the impeller is making the noise. Im probably gonna try to find ceramic bearings for it or atleast replace them.
 
r.brown.bayliss said:
Mine is almost silent buy I can barely spin it, its quite stiff and stops spinning after at most a quarter of a second
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Just got mine in today. Also quite stiff and I would say it stops spinning almost instantly like you’re describing.

I do also recognize the sound from @Miikka1 though, mine makes a similar sounds, just doesnt spin as freely.

I wonder if this is ok? @brettus8 do you have any insight on this?

Added a video:
 
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I have two of these. The bearings they come with aren't the greatest, but so far no problems. Run it in for a bit, and if you're not happy, you can always drop in better bearings. Considering the price point, I didn't expect high end bearings.
 
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