Exhaust Mods in the PRK?

[Svashtar]

I have made a pretty good start on my mods on my 6 month old MM, thanks mostly to all the info I got on this forum: 4:10 gears, stud&girdle kit, MMX driveshaft & loop, 180 stat and cooler MC plugs, megs delete tips, rear sway bar, control arms, Steeda UD pullies, SCT 9100 tune from Dennis, and now a JLT RAI waiting to be installed. (Not counting all the bling stuff that's just for fun!)

I spoke with Dennis today about getting the Cobra exhaust installed, as that is something I have always wanted to do, and learned to my disappointment that neither it OR the kooks system is legal in CA! I knew about the S/C cars being a problem here because my brother-in-law has an S/C'd Cobra with a ton of work into it that he can't drive any longer. But I didn't know about this, and it's a disappointment because I was counting on at least another 25 HP out of the mod.

For those of you in this damned state: are their ANY exhaust mods I can make to the system that will increase HP while still keeping the 4 catalytic converters in place? Would upgrading the mufflers help? Dumb question: would it be worth it to replace all the 2" pipe under there with 2.5" stuff, but keep everything else the same?

Thanks as always for your help and info!

Regards,

Norm

[Directedby]

I have made a pretty good start on my mods on my 6 month old MM, thanks mostly to all the info I got on this forum: 4:10 gears, stud&girdle kit, MMX driveshaft & loop, 180 stat and cooler MC plugs, megs delete tips, rear sway bar, control arms, Steeda UD pullies, SCT 9100 tune from Dennis, and now a JLT RAI waiting to be installed. (Not counting all the bling stuff that's just for fun!)

I spoke with Dennis today about getting the Cobra exhaust installed, as that is something I have always wanted to do, and learned to my disappointment that neither it OR the kooks system is legal in CA! I knew about the S/C cars being a problem here because my brother-in-law has an S/C'd Cobra with a ton of work into it that he can't drive any longer. But I didn't know about this, and it's a disappointment because I was counting on at least another 25 HP out of the mod.

For those of you in this damned state: are their ANY exhaust mods I can make to the system that will increase HP while still keeping the 4 catalytic converters in place? Would upgrading the mufflers help? Dumb question: would it be worth it to replace all the 2" pipe under there with 2.5" stuff, but keep everything else the same?

Thanks as always for your help and info!

Regards,

Norm

I have same mods as you and researched the exhaust.

I decided to keep factory cats then i did 2.5 cat back with magnaflow x-pipe and flowmaster mufflers.

I think i picked up a few HP, maybe 12 HP?

West Coast Marauders are meeting on Feb 5th at LACR Los Angeles County Raceway for 1/4 mile times. FYI

[Smokie]

Exhaust has been my most power adding mod, your local inspection actually look for 4 cats, or just simply put probe in tailpipe and take a reading ???

[Directedby]

Exhaust has been my most power adding mod, your local inspection actually look for 4 cats, or just simply put probe in tailpipe and take a reading ???

In California they do a physical inspection and a reading via sensors/computer into exhaust system.

[Smokie]

In California they do a physical inspection and a reading via sensors/computer into exhaust system.Florida use to have inspections, they looked under car for obvious holes, but passing was based on whether the probe they put in tailpipe gave a passing reading.... the reading is what determined pass/fail, not how many cats.

Too bad, the SVO Shorties and all the rest back to the tips gave me a serious torque boost. Plus great sound.

[maraudernkc]

How often do you get tested in CA.?




I have made a pretty good start on my mods on my 6 month old MM, thanks mostly to all the info I got on this forum: 4:10 gears, stud&girdle kit, MMX driveshaft & loop, 180 stat and cooler MC plugs, megs delete tips, rear sway bar, control arms, Steeda UD pullies, SCT 9100 tune from Dennis, and now a JLT RAI waiting to be installed. (Not counting all the bling stuff that's just for fun!)

I spoke with Dennis today about getting the Cobra exhaust installed, as that is something I have always wanted to do, and learned to my disappointment that neither it OR the kooks system is legal in CA! I knew about the S/C cars being a problem here because my brother-in-law has an S/C'd Cobra with a ton of work into it that he can't drive any longer. But I didn't know about this, and it's a disappointment because I was counting on at least another 25 HP out of the mod.

For those of you in this damned state: are their ANY exhaust mods I can make to the system that will increase HP while still keeping the 4 catalytic converters in place? Would upgrading the mufflers help? Dumb question: would it be worth it to replace all the 2" pipe under there with 2.5" stuff, but keep everything else the same?

Thanks as always for your help and info!

Regards,

Norm

[MarauderMark]

Florida use to have inspections, they looked under car for obvious holes, but passing was based on whether the probe they put in tailpipe gave a passing reading.... the reading is what determined pass/fail, not how many cats.

Too bad, the SVO Shorties and all the rest back to the tips gave me a serious torque boost. Plus great sound.


So getting 4 high flow cats won't work or would it make it worse?

[Directedby]

How often do you get tested in CA.?

Was after 4 years, then every 3 years.

But heard now every 5 years was instated in 2005.

[Directedby]

So getting 4 high flow cats won't work or would it make it worse?

CATS in California are tough as hell and need to be CARB certified. In the viz expection they look and must find the CARB stamp or plaque or see that it is a factory CAT.

I hear that the Cobra Manifolds will pass viz expection because they have the 'ford' logo stamped on them and they look factory. However, the hi-flow CATS that come with them will not pass the fumes test.

[Svashtar]

I have same mods as you and researched the exhaust.

I decided to keep factory cats then i did 2.5 cat back with magnaflow x-pipe and flowmaster mufflers.

I think i picked up a few HP, maybe 12 HP?

West Coast Marauders are meeting on Feb 5th at LACR Los Angeles County Raceway for 1/4 mile times. FYIThanks very much DB. I'll take this to my muffler guy, who is actually very good, and see what he can come up with. I'm not into fearsome sound, and the delete tips sound nice, but a bit throatier would be OK.

Thanks also for the LACR reference!

Regards,

Norm

[SouLRioT]

It might not add as much HP, but if you changed out the manifolds, wouldn't they pass visual inspecton? But the best person to talk to is NAVCHAP.

[FordNut]

If I lived in the communist state you do, what I would do is upgrade the mufflers and add a x-pipe along with larger tubing from the OEM flanges behind the cats. That's step 1. Then unbolt the cats and have a set of custom high flow cats welded up to fit the OEM manifolds and flanges to the x-pipe. That's step 2. Then at inspection time I would swap back to the OEM cats for the emissions inspectors and swap back immediately afterward.

The performance gains would not be as great as with the Cobra manifolds, but it would be much easier to convert the cats back to stock for inspection.

[MarauderMark]

If I lived in the communist state you do, what I would do is upgrade the mufflers and add a x-pipe along with larger tubing from the OEM flanges behind the cats. That's step 1. Then unbolt the cats and have a set of custom high flow cats welded up to fit the OEM manifolds and flanges to the x-pipe. That's step 2. Then at inspection time I would swap back to the OEM cats for the emissions inspectors and swap back immediately afterward.

The performance gains would not be as great as with the Cobra manifolds, but it would be much easier to convert the cats back to stock for inspection.


Damn good answer Sir!!he might be ok i mean the cobras are factory manifolds for a cobra .if they are not polished do ya think they will be able to tell?

[FordNut]

Damn good answer Sir!!he might be ok i mean the cobras are factory manifolds for a cobra .if they are not polished do ya think they will be able to tell?
The only problem I see with the Cobra manifolds is the outlets are positioned differently from the MM. So the stock cats wouldn't bolt back up. And the Cobra system doesn't have flanges after the cats located in the same place as the MM. So it's difficult to mix and match, it just about has to be a complete swap if you want to change manifolds.