Twinky

The AMR500 is always on, max blower continuous speed is 16,000 RPM. The VW blokes overdrive them at a 2.1:1 ratio and set max engine rpm to 8,000rpm. Either way I'm not aiming for that kind of rpm, I've set my redline to 6,000 rpm and I barely even take it to 5,000 rpm as it is anyway. Cheers for the info guys!

I say that it's a bit much because there will be a turbo going on as well with no bypass valve. So lets say that my supercharger is putting out 7psi and my turbo will add another 7psi on top of that. Whereas if the supercharger was putting out 11psi the total boost would be around 18psi, a bit too much for a standard motor. The AMR500 has a safe operating speed at 15,000rpm, at even 2:1 it would only see 10,000 maybe even 12,000 peak rpm.

Yeah I did think of that but it's the rarity of it that puts me off. Basically my idea is to got to a wreckers and look at something like a celica/civic/magna.

Any automotive paint supplier worth their salt should be able to identify the colour or at least have a 99% match.

While I am here I might do the calculation for my next pulley up size! 5000rpm x 2 x 0.5 = 5000 ltrs / min 5000 / 2812.5 = 1.77 ((1.77 x 14.97) - 149.7) = 11.5psi Holy shiznit! maybe going up to 2:1 ratio might be a bit too much.... 1.7:1 should give me nearly 8 psi. That sounds more reasonalbe.

I guess that's the unfortunate nature of equations, they are too specific in where real world values can be so variable that the equation can only be used as a guide. Lets just play around with it though. Lets say that I do in fact have 75% efficiency: 1.5 x .75 = 1.125 x 5000rpm = 5625 / 2 = 2812.5 ltrs / min 3psi + 14.97 (atmo pressure in Adelaide as of Monday) = 17.97 / 14.97 = 1.2 (so only a slight variation) 2812.5 x 1.2 = 3375 ltrs / min @ 3psi 3375 / 0.5 = 6750rpm (supercharger speed) 6750 / 5000 = 1.35 pulley ratio (3.6% difference to my 1.4 ratio @3psi) So after the amendments this seems to be alot more accurate in regards to real world figures. Maybe that could be added as a footnote to the text of that FAQ/WIKI section?

Yeah no worries, It's just that the calculator could be a bit misleading so maybe a forewarning that it should only bee used to get a rough idea or something along the lines of that. Thanks for your input though as at least there is a few people who have used the calculator with some reasonable results.

Wasn't it called willow green or something?

The AMR500 is a 500cc per revolution supercharger, which is the 0.5 in the calculation.

Hi guys, As anyone with an original 4k EFI manifold would know, the throttle body is tiny. So tiny in fact that you can not buy any adaptors for CAI tubing. Because of my twin charging ambitions I can not reliably seal the throttle body thus boost would escape. So what I am looking at doing is upgrading to a 2" throttle body as this is a standard size for piping and intercoolers. The question is what throttle body should I look for? I want to find something that I could easily modify to fit the standard KE55 throttle cable and has a resistive type TPS. I know it's not something that everyone does but if anyone has done something similar I would like to know. cheers

Hi guys, Recently I have Fitted a supercharger to my EFI 5k. The supercharger is an AMR500 with a 70mm charger pulley and a 100mm crank pulley. My first question is about the calculator used in the FAQ/WIKI section relating to the calculation of boost. Has anyone used the calculation and had a correct answer from it? From my initial calculations the answer came out to be a negative boost number because my pulley ratio is too low according to the calculator. From memory my calculation was -0.9psi. So for shits and giggles I decided to whack it on anyway to get the ball rolling on the project and then find a bigger pulley later. To my surprise the supercharger actually put out 3psi. Now I did a second calculation to see how things fit in, I'll actually write it all down. 1.5ltrs x 5000 rpm = 7500/2 = 3750ltrs/min (determining air requirements at 0psi) 3psi + 14.7 = 17.7/14.7 = 1.204 (boost ratio) 3750 x 1.204 = 4515lts/min @ 3psi (air requirements at boost) 4515/0.5 = 9000 rpm (supercharger speed) 9000 / 5000 = 1.8 (pulley ratio for 3psi boost @ 5000 rpm So already you can see that there is either a slight error in the calculator or just that the calculator can not take into account all aspects. I don't know I'm not a mathematician but My ratio is only 1.4 and I get 3psi. at 1.8 I would be roughly getting 4-5 psi in real world. Has anyone else had any experience using this calculator? cheers

Arcing means that the spark is jumping across two conductors. Being that the crack is on a terminal it is more likely that you are getting no spark at all intermittently. But that is worst case scenario, I've had a crack similar to what you are describing and it worked perfectly well. I think that if you replace the dizzy cap, get a new rotor button and new points then you should be fine. If it still misses after this you may want to replace the ignition leads and spark plugs. Before you go ripping out your points have you ever set your points gap before?

How much does Brenton ask for a tune these days? When I get a bit more boost I'd like to take my car to him as more power did a crappy tune when I had it done there.

Clean whatever can be cleaned to a satisfactory condition but definitely replace any damaged parts. If the dizzy is the catalyst of the misfire it sounds like a sark is arcing to something it shouldnt. What exactly is cracked?

tuned a couple of flat spots out and I can now feel the supercharger doing some work!