Does anyone know which performance exhaust might do best on a new 2002.5 P5? Will it affect the car's ability to pass emissions test in Virginia? Also, is there a supercharger available for this car (P5) that will fit under the hood without making holes in it? Thanks for any replies.

 

I beg to differ...

 

Pseudo, I wonder about this statement as well. As I seem to recall, Vortech's supercharger kit for the Civic Si was better than that of the Jackson breed......

 

The S-2000 is a peaky motor at best, why in the world would you want more power on top of that?? A centrifugal supercharger is essentially a turbo run off the crank, hence more top end power, which is worthless on a car that already has top end power, such as most Hondas. Sure you make more power, but who cares if it all at the top? I don't know about you, but I don't prefer to drive around town at 6000 rpm just to make sure I have useable power.

A roots type blower (Jackson Racing set-up) just packs more air in, it really doesn't compress the air like a turbo does. So, at altitude a 6 psi (sea level) roots blower is really maybe only making 4 (and nothing at all on top of some of the high passes around here), at best. Just about worthless if you are up in Colorado, which I am.

If you want to go forced induction at this time, a turbo would probably be your best bet. If you really want a supercharger, rumor has it that Area 51 is making a centrifugal blower set up. It is currently on the Wings West Protege as a test.

Like Psuedo said, there are a few turbo kits out, and they all make boost lower down in the power band, which is beneficial to the Protege. That's my two cents though, do what you want, have fun.

 

I think that most people are interested in superchargers because of their ease of installation. Instead of using spent exhaust gas, you simply run it off the engine. Isn't that easy?

 

IMHO it is easier to install a simple supercharger setup than a turbocharger. But I would not waste my money on a supercharger for a 4-cylinder. You will really be limiting your upgrade path. Get the turbocharger.

 

If you want to get into the debate on the worth of a supercharger...goto the Forced Induction forum. I am gonna agree with psuedo on this debate though. The centrifigul supercharger is great for landspeed records or something like that. They are run off of step gearbox not directly off the crank like a roots blower. The Vortec Civic SI may have made almost 280 hp, but the fun didn't start until about 5500 or 6000RPM (dyno and carpet queen). A big M62 eaton blower would be awesome on the proteges. This is the same blower off of the Turbo T-birds. You could get about 200hp easy with an intercooler and a little tuning. I can't wait till someone releases a roots blower for the FS-DE. I will purchase it in a heartbeat.

 

To answer the original question - an exhaust should not affect emissions at all unless you replace the cats. Once you get past the second cat, it's basically just a pipe. Both Thermal and Racing Beat make exhausts for the P5. We haven't tested either on a stock car yet, but the Thermal did great things for our turbo car.

As someone who has installed both SC and turbo systems, there's no big difference in installation effort if the systems are comparable. In other words, there are a lot of half-engineered SC systems out there. Same with turbos. And if you leave things out (IC, fuel control, etc) then it's easier to put in. A proper SC will have you pull the intake manifold, and that's a lot harder than pulling the exhaust manifold for a turbo.

I can't think of a worse setup than a centrifugal SC on an S2000 engine. Wow.

Keith

 

I was not arguing that superchargers are better than turbos on small engines, but if you have an engine that you are going to be revving in the high rpms anyway, a supercharger is just as good as a turbo. They both have their good points and their downfalls. I was just saying that the amount of hp a supercharger adds is significant to any engine. Sure the S2000 charger gets peak power at what 8500rpm? But that is and engine that like to be revved high anyway. And look at the TQ graph on the Civic, we are talking a nice usable amount of TQ increase starting down at 3000rpm. That is useable power!

 

I do agree with you there. The roots type is an excellent choice in SCs. That is why the Fords use them (Lightning, Cobra, Focus, Harley, Rousch, Saleen and Steeda I believe) It is also a factory part you can buy from their motorsports division. Why won't someone make that type for our cars?

 

If you think the Honda graphs show useable power, it's time to start driving cars and looking at their dyno sheets.

Pseudo is right - don't make generalisations about superchargers and include both positive displacement and centrifugal ones in the same group. They have opposite characteristics - the centrifugal is all top-end, the positive displacement is all low-end and falls off at the top.

Actually, I believe the SVT super is a centrifugal.

The Roots is unfortunately an inefficient blower. The OEMs seem to like it, but it's not always the best choice for good power or an exciting engine.

Keith

 

Keith, maybe I don't know what I am talking about. I was just looking at numbers. The increase in TQ # on the Civic seems to be pretty significant, would that not be usable power?

FWIW, I plan on going FM turbo when the funds become available. Unless something in the SC category just blows me away, which I doubt it will. I can't wait to see the final numbers on the FM Protege. Keep up the good work.

 

Well, I've also driven a 360 rwhp Miata on the street on 195/50-15 tires and didn't have any trouble with wheelspin, so maybe it's because I'm not WFO all the time I'll agree that it's certainly possible to light up the inside tire pretty well. It's not exactly an autocross hero at the moment, but it's great on the street.

Sorry, can't make it to Nationals. But say hi to Dan Pedroza in SM2 - he's running an FM II equipped Miata and is a quick guy!

You can't just look at numbers. You need to look at the shape of the curves. Cars with a narrow powerband just aren't as useable in the real world as ones with a big fat flat torque curve. The steeper the curves, the less useable the power is. Ever driven a 2.5RS Impreza? They've got a great torque curve, part of why they're so easy to play Rally Hero in. You still want some top end, but not ALL top end.

Keith

 

Or you can get the Kc5zom special for $5000. Adds 99.9% to your bottom end torque and horsepower! Proven results when measured at 0 rpm.

 

Stay tuned. I've got engine management now and I'll be installing it this weekend probably. Can a supercharger be far behind? That M62 I've got sitting on a shelf is eating at me. Yeah, it will be a bit of work to fabricate an intake. Yes, it will be a bit of work to set up additional injection and a drive system. But it can be done....