4AGZE Supercharger Problem

[Patrini]

Hi, new to this forum I have an AE92 4AGZE fitted to a Clubman kitcar.

4AGZE has 165mm crank pulley, Welded SC pulley, ABV mod and I believe everything else is stock.

I seem to have a problem with the boost developing at too high a point in the revs and would like to ask a few questions to assist with the troubleshooting process.

So far I have checked for leaks and tightened the SC drive belt.

1. I get 5psi of boost at 5,000rpm and finally get 8psi after sometime at max revs. I notice the manual mentions getting boost at 2,000rpm. What revs should I see max boost developing ??, I am assuming it should be lower than I am getting.

2. It seems that if all else is correct perhaps the SC itself is worn, are there any easy checks?? What sort of KMs do they normally last ??, mine has done approx 30,000km under mainly high speed tarmac rally conditions so would expect wear to have been accelerated compared to normal road use.

Thanks for any assistance.

Chrs, Pat

[TERRA Operative]

The easiest way is to pull the supercharger out and look at the lobes. If they're scored etc. it's stuffed.

Also if you measure the clearance on the front and rear of the lobes, you should have 1/3 clearance on the rear side (as per rotation) and 2/3 to the front.

Also, if you take the gear housing off and check the backlash on the gears, you shouldn't have anymore than 0.1mm at the absolute most.

Holden supercharger oil can be used to refill the oil chamber ask for part number 12345982. It's about $32 or so for 120mL.

[Patrini]

Thks for the reply, very helpful.

Can you help with the other querie above :

'What revs should I see max boost developing ??'

Chrs, Pat

[TERRA Operative]

I see max boost at 6000 RPM or so, with it steadily climbing until then.

[Adsport]

sounds like your s/c is busted up... you should have max boost before 2000rpm with WOT. with the pulley ratio you listed you should be making at least 11psi.