I'm currently deployed in Iraq. One of my buddy's is an Rx-7 fanatic.. he's going to sell me his 88 Fc when we get home... we've been discussing things we can do to it to give it a peformance increase further down the road. We've been talking about porting.. engine swap and turbos... but recently we came across the idea of supercharging it... My question is.. is a supercharger worth the money it costs.. i was looking around and it says that it can give a 35-50% horsepower increase with a stock engine.. is this true? and if it is... is the supercharger all i need or would a carburator be needed? thank you for any help you an offer

 

It will be an entirely custom job, unless you want to fork out about $3500 for a kit, and those are getting a bit hard to find. I've heard of them done with carb and fuel injection, but you really don't see many around for the simple fact that you can get more power with half the money involved by converting to turbo, and that's mostly because the turbo parts are far more common. You can actually buy a complete turbo engine for less than half of the cost of a supercharger kit for an FC. That said, it would still be a neat project, and other people have done it, so you should be able to search various RX7 forums and find lots of info.

 

If you are one of those who chooses the road less traveled, then by all means, go supercharged. But if you're looking for the same kick in the pants and want good availability of parts, lots of options, and the experience of lots of people who have been there before you, go turbo.

 

Might want to touch base with Pettit Racing as I think they did some work with the RX-8 with a Roots Type Blower

 

well there use to be a centrifugal supercharger kit by Paxton/Nelson you might find a used kit for sale. also Camden superchargers makes a roots type blower kit. the kit is nice they now have a fuel injection kit. mine was originally carbed but i made my own fuel inj. set up. i have seen rotaries with old GM 6-71 blowers making gobs of power but a little on the expensive end to fabricate. i own turbo, supercharged and naturally aspirated 7's, i enjoy driving them all. as far as the cost it is a little cheaper to do a TII swap but once you start upgrading cost is a lost battle. good luck either way.

 

most supercharger installs try to get more low end out of the motor, and as a consequence are too small up in the higher rpms.



so an NA with a mild street port and no cat will have a similar peak hp number to a supercharger kit

 

turbos have become the ideal choice in building a car. the reason behind this is the much aftermarket support and the fact the car came in a turbo model will sway most people to follow suit. the kits i listed above one a roots type blower is yes goiung to give you the low end grunt, but a centrifugal blower with a step drive will gain power through the rev range. both kits are not powerhouses in how they come but with the right additions like a turbo and boosting up will notice real gains. like i said i have naturally aspirated, turbo and supercharged rx-7's. on my supercharged i decided to have a custom boost pulley made and i had the a custom main pulley made to over drive the charger futher increasing boost. to ensure intake temps werent too high i had a custom water to air aftercooler made that sits between the blower and the manifold. cool and dense air, alot of fuel and good ignition timing, makes for decent power. now these kits availible dont come with theses items and can be costly to end up with something similar to what i have, so in respect of cost my turbo car makes more power then the other two and cost a little less then the supercharged as of now.