OK, the easiest way to pass CARB is not to touch ANY smog control from charcoal filter in the air box to the twin CATS. Here’s a turbo idea that does just that.

Stock header, down pipe to second CAT, after that U bend it back to the front of the car and into a turbo, sure there is like3 feet of “extra” pipe but this is a big engine so the slight lag ain’t much. No need to make turbo manifold! For the intake stock air box, 90 degree bend forward into the turbo. Looks like the ECU works just fine with boost add 500 cc injectors and intercooler if you want, BOV must be a bypass and dump back into the intake post MAF, wastegate should go into the down pipe. A little extra pipe under the car, may have to do oval pipe for ground clearance,

So what do ya think?

 

i have been thinking the same thing for about 1 month now not as in detail but i seen a company started selling turbo kits like this for hondas so they can still pass emisons tests

 

Hmmm...

-Cat 1? Check.

-Cat 2? Check.

-Carbon filter? Check.

-Evap system intact? Would rerouting the intake piping to the turbo effect the Evap piping? I'm not really sure, I'd have to look at the service manual (don't have it with me), but I thought there was some tubing for the Evap system that routed into the stock airbox. I'm probably mistaken, but it's something I thought of.

What about the piping for the turbo itself? Picturing the tC's underbody off memory, around the second cat, it seems like there'd be an issue routing the piping. Even with oval piping, iirc, the piping would have to route down and around the heat shielding that's around the exhaust.

Considering the extra piping, what kind of turbo did you have in mind? Given that the turbo would be fed from 2.25" piping, that's pretty far down stream of the exhaust manifold, what do you think the power curve would look like? I could see the small piping being advantageous for quick spooling, but towards the top of the RPM band I could imagine the power possibly dieing off due to exhaust velocity constraints imposed by the exhaust piping or would that not be an issue?

I guess my primary concern is that this type of setup would be neutered like the TRD S/C in order to keep it CARB legal. Not really an assumption, just a concern. What do you think? Sounds like a damn good idea though.

 

to pass smog you will have to dump the evap into the turbo intake, mean nasty way to do it but with a vapor seperator inline like a MBenz unit it won't be too bad. We all know you going to just dump it to the ground after the check anyway

the is one company putting the turbo WAY WAY out by the muffler! I'd still go with the Evo turbo or a small t3 one. Spool will be effected, but this is a big engine.

I would think that 220 (non intercooled) to 300 whp could be done with reasonable boost levels, after that you should be looking at a REAL turbo system. The supercharger is a belt driven centrifical unit meaning it is not very flexible in relation to boost, also TRD has to worry about a warranty, last it would be much harder to fit an intercooler into the TRD setup.

also the exact law may say "in place and working" then a U pipe could come from the header to the turbo then turbo to 2nd CAT in original place, this would conform to the letter of the law, "in place and working" yet have a turbo inserted inbetween.....

 

ur right... technically u didn't do anything wrong or change the CATs. But, do u think u can pass the pipe tests and stuff like that, cuz i know we have a pipe test in PA. Plus do u think anybody has the ***** to produce one of these. if so im down.

 

oldman, are you still waiting for your ZPI kit, or thinking about Cancelling and making your own turbo...since the stock ECU can manage up to 10psi? Since all the R&D is done for you, that will cut cost even more...you can pick your own wastegate, BOV, injectors, fuel pump...and an intercooler of your choice....!!! I you do, let me know!

 

I'm good with ZPI, I'm just thinking how to do a fully legal kit.

And yes I do think the car would pass full smog, once the turbo heats up, and you know the precat is the one that lights off first and may even work better with a little more restriction in the exhaust.

I don't want to get into building something from the ground up as I have near zero time and am close to just buying an A3 FSI or a GT Mustang 05...

 

We thought of this also but the stock ECU will not control 500cc injectors. We havbe tried this first hand the car floods itself at idle.

 

I am close to builing a factory five MKIII roadster or a new GTM kit to blow close to everthing on the road aside from maybe the ENZO or the Ultima GTR car :D

 

Oldman for president? any 2nds?