Supercharged TJ

[Tjjeep]

I recently installed a Eaton M90 supercharger in a TJ wrangler and thought it would be well worthwhile sharing the experience. The Eaton M90 is a common supercharger that is installed on many holden commodores. They are readily available on ebay at a good price, the one for this project was $250. Stock they supply the holden at 6psi but can easily go to 10 psi. The Eaton M90 fits very conveniently where the air conditioning pump sits. It can be mounted upside down and does not need any plumbing for oil making for a simple install. You will need to fabricate your own manifolds, I did this with carbon fibre and aluminium. The result is the 4l six pumps out some serious torque when running at even 4 psi. The first stage of this project the supercharger is plumbed direct to the throttle body. Next phase is an intercooler with water and methanol injection to reduce charge temperature.

[Tjjeep]

[bruggz351]

Thats cool man.
What has been done to the bottom end for the blower?
Standard PCM or aftermarket computer?

cheers

[deanfoldi]

I can only dream ha ha.

[Tjjeep]

The outlet manifold with the first lay up of carbon fibre. Once set you can then disolve the foam core with thinners.

[Tjjeep]

The intake manifod was made form 6mm aluminium sheet with carbon fibre to make up the outlet shape. The inner core was made from foam styrene, then sealed with thin plastic to stop the resin dissolving it. Post lay up you then remove the core with a laquer thinners. There are many alternatives for the form from clay through to play doh or other types of foam. This was a lot easier than fabricating the manifold all form welded aluminium and made for a smooth flowing internal shape.

[Tjjeep]

The Charger is currently plumbed straight into the throttle body. The Eaton has an internal bypass valve that is actuated by both vacuum and bost pressure. This works well but does however recycle all the charged air increasing the air temp. To over come this there is a blow off valve mounted on the intake manifold. Via an in cabin boost controllers you can select boost levels and also how much is dumped through the internal bypass valve and how much through the blow off valve. The blow off valve releases excess charge to the atmosphere which provides better performance but also makes a lot of noise. Currently she is running the stock PCM with and adjustable MAP sensor and an intake temp bypass, the downstream o2 sensor has also been disconnected and running the highest octane fuel I can find I have been very suprised at how hard she goes with this configuration. You can make her knock if you floor it at low rpm's especially is she is running hot, but if you are wary you can avoid any pinging. Next I plan to convert the engine management to a MegaSquirt System