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AMR300 rev limit?
https://www.ausmini.com/forums/viewtopic.php?f=5&t=33864		 Page 1 of 2
Author:  spraycanmansam [ Sat Jul 14, 2007 9:45 pm ]
Post subject:  AMR300 rev limit?
Does anyone know the rev limit of an Aisin AMR300 supercharger?

I worked out I'd be spinning it at a tad over 20000rpm ... :shock: :shock: ... :shock:

I think I already know the answer to this one... :cry:

I think supercharged850 might know some more on the matter...
Author:  TK [ Sat Jul 14, 2007 10:51 pm ]
Post subject: 
did you google "Aisin AMR300 supercharger"

or maybe pm supercharged850 if he knows more on the matter.

:)
Author:  spraycanmansam [ Sat Jul 14, 2007 10:54 pm ]
Post subject: 
TK wrote:
did you google "Aisin AMR300 supercharger"


um no.. why would i do that? ... :roll: it's not a very popular supercharger so information is few and far between :(

just wondering if there's anyone else who would know more on the matter...?
Author:  slinkey inc [ Sat Jul 14, 2007 11:16 pm ]
Post subject: 
I had a look at one of these when looking around for a 4EFTE (it was on the shelf in the shop). They are very small. Possibly with big rpm they might produce some decent boost, but superchargers usually run inefficiently when overboosted but who knows with these.

After a quick search I've found some unofficial numbers. AMR300 is 300cc per revolution, SC12 is 1200cc per revolution (makes sense). AMR500 is 500cc per revolution and SC14 about 1420cc per revolution.

If this is true, and the number in the model name of the charger is to do with the capacity per revolution then it seems that you'll need to spin the AMR300 very fast. Should be fun. 8)
Author:  spraycanmansam [ Sun Jul 15, 2007 12:29 am ]
Post subject: 
Yes very fun indeed... :P I just dont know how reliable a supercharger spinning at 20000 rpm (thats what I worked it out to produce 10 psi on my 1100) I'm thinking melted rotors, etc? Unless someone can assure me otherwise?... :?
Author:  supercharged 850 [ Sun Jul 15, 2007 1:22 am ]
Post subject: 
The info is out there...... :wink:

The AMR blower, factory fitted to the 660cc Subaru REX VX, is geared to spin at 1.7676 times the engine speed. Knowing that the REX VX is capable of around 7500rpm, you'd expect the blower to spin at 13200rpm at the same time....... however, it does not produce useable boost at that speed. The blower seems to be most efficient from engine speeds of 1000 to around 4500rpm at the crankshaft (or blower speeds of 1700 to 8000rpm), with power dropping off at speeds above that.

If you were to go for an AMR500 instead of the AMR300, you will increase capacity, and increase boost by around 50% at the same rpms.

You can safely gear these blowers to run at just under 2x the engine rpm, but only if you limit yourself to 6000rpm. The blower pulley is 55mm diameter, so aim for a 107mm pulley to drive it.

**edit - I found an old old old thread with some of my info in it...
http://www.ausmini.com/forums/viewtopic.php?t=659
Author:  slinkey inc [ Sun Jul 15, 2007 10:39 am ]
Post subject: 
I should mention that I'm doubtfull you'll make 10psi.

The heat produced by that charger at that boost is going to be so big (that's the inefficient part) the fuel air mixture is just going to detonate. Ideally you want to keep the fuel air rather cool in temperature, as the more heat, the higher the average kintic energy on the fuel or air particles. Which results in a greater rate of reaction (fast burn which leads to uncontrollable detonation). Theoretically if the temperature of the air was hot enough the mixture would go bang immediatly, but your not going to make that much heat.

That's also why need to run lower compressions for bigger boost, due to heat. 10psi max for 9:1 is generally an accepted rule of thumb, with 98 octane fuel.
Author:  1018cc [ Sun Jul 15, 2007 10:44 am ]
Post subject: 
slinkey inc wrote:
I should mention that I'm doubtfull you'll make 10psi.

The heat produced by that charger at that boost is going to be so big (that's the inefficient part) the fuel air mixture is just going to detonate. Ideally you want to keep the fuel air rather cool in temperature, as the more heat, the higher the average kintic energy on the fuel or air particles. Which results in a greater rate of reaction (fast burn which leads to uncontrollable detonation). Theoretically if the temperature of the air was hot enough the mixture would go bang immediatly, but your not going to make that much heat.

That's also why need to run lower compressions for bigger boost, due to heat. 10psi max for 9:1 is generally an accepted rule of thumb, with 98 octane fuel.


Listen to slinkey! You will need a rather large intercooler if you are running 98octane fuel. If you don't have a intercooler the intake temps will be so high that the fuel will detonate (like slinkey said). If you can't run a 'cooler you would have to start looking at racing fuel (i.e. 110 octane racing unleaded etc) so that it doesn't detonate.
Author:  slinkey inc [ Sun Jul 15, 2007 10:57 am ]
Post subject: 
I was assuming he was going to run Carby > Charger > Motor.

Of course a nice big intercooler would work wonders.

Then you could run Charger > Cooler > Carby > Motor. Of course never fuel air into a cooler just air :wink:
Author:  1018cc [ Sun Jul 15, 2007 11:34 am ]
Post subject: 
Yeah that's what I meant. I should stop assuming people will understand what I type. :oops:
Author:  spraycanmansam [ Sun Jul 15, 2007 1:09 pm ]
Post subject: 
Thats the info i needed... I thought it was going to be too small. Its just that one was going for $200 with an intercooler! :P

Yeah spinning it at 20000rpm the intake temps would get pretty damn high i imagine!

slinkey inc wrote:
never fuel air into a cooler just air


I've seen someone draw through with an intercooler... :shock: :shock: .. a bomb waiting to happen...

Thanks guys
Author:  slinkey inc [ Sun Jul 15, 2007 4:01 pm ]
Post subject: 
:shock:

If it backfires through the inlet (pre-igniton) things could go real, real bad.

As you say "A bomb waiting to happen". Although I've never seen it happen, nor seen anyone with setup, just read about the dangers.

Oh forgot to say, thought of water/methanol injection? Some poeple consider it 'dodgy', but I think if setup right should be quite good.

<edit> They used to use meth injection in WW2 bombers on the supercharged engines to reduce detonation.
Author:  spraycanmansam [ Sun Jul 15, 2007 4:27 pm ]
Post subject: 
Yeah I was talking to the guys on turbominis the other week with the idea of water injection.. which is what I'd use if I set it up like the Vmax Scart setup.


This is that car :shock: --

Image

Everyone was surprised that it actually worked and the fuel didnt just puddle to the bottom of the cooler... haven't heard from him since :P
Author:  Kennomini [ Sun Jul 15, 2007 4:37 pm ]
Post subject: 
I'm doing the same thing :) . So far this is my fitment on a spare donk i got, still needs more plumming and fiddling but it's mostly their. I am wondering how the charged will go with the way it's driven off the water pump, what rpm dose the waterpump spin at in relation to the engine
TRYING TO POST SOME PICS
Author:  spraycanmansam [ Sun Jul 15, 2007 4:47 pm ]
Post subject: 
Are you using a AMR300... or are you building a intercooler bomb like above? :P

What size engine are you using?

I know supercharged850 was going to run his AMR500 off the water pump...
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