I was told that in order for me to switch from stock twins to a TO4, I would have to remove the air pump to accommodate it. Is this true? If so, how do you TO4 guys pass emissions?

Any information regarding TO4 and emissions facts/advise will be greatly appreciated. I have a TO4 and all the neccessary parts, but will think twice before installing it due to the emissions regulations.

Thanks

 

It depends on which t04 kit you have. The HKS kits allow the airpump to be retained. I have the HKS t04e and I expect to be able to tune the car and pass emissions without a problem. The XS kits require airpump removal.

If you have a custom kit, whether or not the airpump can stay in place depends somewhat on which manifold you use. The cast iron HKS models keep the turbo low enough on the engine to keep the pump. I don't know about the other brands, though.

Some people who have removed the airpump have temporarily installed a corvette electric airpump to pass emissions, but it cannot be setup to run continuously, and should run at most a couple of minutes nonstop.

 

This is the one I have, http://cgi.ebay.com/ebaymotors/ws/eB...&ed=1076084413

 

That's the OBX or similar manifold. You can't keep the airpump with that one; it places the turbo too high. The runners on the HKS aren't as long and are nearly horizontal when the manifold is mounted. Sorry.

 

Argh.. not the answer I wanted to hear, but thanks. Does HKS sell the just the manifold?