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supercharger on an ea81

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the SC12 weighs 24lb on a trike weighing 1100lb. On 5psi only its performance increase is remarkable.


As a comparison, on my way home I have a large hill about a mile long. Its steepness is such that with the 1916 VW engine twin webers at the steepest section it is flat out at 40mph in second gear on the 3 speed auto. With the stock ea81 Subie engine 50mph second gear, with the supercharger on a richly tuned engine 65mph maintaining top gear and likely could have gone faster but didnt want to push a rich engine.


My other purpose of the SC apart form general overall performance is low torque for pulling our trailer/caravan which I havent tested yet.


Having had this sC installed for the last 3 months or so I'm so satisfied with this easy set up, no electronics, no complications and an easily maintained engine...I'd recommend it to anyone wanting the same. For the above reasons supercharging a ea81 is a real alternative to the EJ series IF thats what you have already and want extra power and low down torque without the conversion issues.


Our trailer. you can google ChevronRV Guppy



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Nobody mentioned the VW G-lader supercharger off the 1.8 G60 engine!!


its unique, its cool, its appropriate for the engine size.

It can be run with inlet and outlet tubes (doesn't need to be mounted to an intake manifold etc) and can run with an intercooler if you wish.






(I owned a couple Corrado G60's in the past, I've rebuild that supercharger before. I recommend rebuild be left to a G-lader professional. Only downside, supercharger should be rebuilt every ~30-40K miles probably)

Edited by TajMan

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Well this thread has drawn to an end now.


I got my dyno tune and it found that the idle jets on the 40 dellorto were too large at 52's. now they have 45's.


Same output. recalibrated dizzy. all good.


82 HP at the wheels about 100 at the flywheel.


Water injection working on boost completes the package.

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You should bump the boost up some more. It was capable of 5psi on the previa with a 2.4l, it should be capable of more on a 1.8l. With the hp increase from 5psi, think of what 7.5 would get you. With the water injection you should be able to run that pressure without any reliability decrease.


I'm severely overspinning an eaton m62 on a 3.4l engine. The 12.5psi it turns out make it a lot of fun too, and it's on an "unprepared N/A motor" with 9.6:1 compression and no intercooler. Water/methanol injection makes it work, and it's been reliable for 3 years with a lot of abuse. I've got less than $600 in the whole setup, so you can have fast/reliable/cheap all at the same time with water/meth injection.


The merc's came with an Eaton M45, which would be a much better size for a 1.8l than an M62 or m90 or m112. The whipples off a millenia suck because the oil seals go out early and often on them. Not much use in a supercharger that injects a mist of engine oil all the time.

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