New exhaust to complement supercharger?

[VehiGAZ]

Howdy all,

Well, I picked up Zooper-Trooper's Alpine supercharger yesterday and brought it home. I have a performance shop lined up to do the install, but I am wondering if the s/c'd engine would benefit from a new higher-flow exhaust system. I searched the forum, but most of the threads focused on modifying the exhaust sound rather than helping engine performance.

My questions are:

1) Would I benefit significantly from a new exhaust system?

2) If so, do I need just the muffler to improve flow, or do I need headers and piping and who-knows-what-else as well?

3) What systems are out there to choose from?

I don't want to say price is no object, but I don't want to spend a $G on this either. Any solutions costing less than $600 or so are up for consideration.

Thanks for the info!

[Ascinder]

Can't remember where I read it, but superchargers are supposed to benefit greatly from increased diameter exhaust pipe and high flow catalytics and mufflers. I know there were some headers made that went on the vehicross back in the day, but I heard they didn't do much horsepower wise and developed cracks rather soon. I would PM or email Tone since he probably has more experience in the area than most. I would also try to search some of the older posts containing dyno information after the supercharger install. Just remember that usually higher flow exhaust usually gives out horsepower at the cost of low end torque, so unless you've done gears on it, it might be a little slow on the uptake.

[Tone]

Yes, but do not go much bigger than 3" to keep low end toque. True duals are a big help but again stay close to stock diameter but with better flowing mufflers - your performance shop should be able to help you but 6cyl are NOT like 8s - make sure they have experience with smaller engines.

[Bulldoggie]

Cyrk has spent $$$$$$$$ on many different exhaust mods, and dyno tested most.

If I had money to ????

[Cyrk]

I have had a Brullen muffler with the stock motor. The I upgraded to the PowerVault Generation 1 Catback. I added the SC and had it dyno'd then. But not before... It dyno'd 216.21HP the I added a custom 2.5 Stainless Steel pipes all mandrel bent and tig welded into Magnaflow cats into a Single 3' in Dual out Magnaflow XL muffler with dual 4' resonated tips, new dyno with that... 225.36. bout 9hp more.

This thread is when Johnnyapollo and I had our VX's dyno'd together on a 4wheel dyno... some good stuff... We were running pretty much the same mods (catbacks, intakes) only that I had the SC on and he did not.
http://www.vehicross.info/forums/showthread.php?t=6423&highlight=Dyno

Also a thread where I got the new on fabed up:
http://www.vehicross.info/forums/showthread.php?t=7946&highlight=Dyno

[VehiGAZ]

Hey Cyrk,

Yes, I remember your ugly muffler job and it's replacement! (I'm glad it all worked out in the end). It sounds to me like I wouldn't be able to get more than a small boost in power from a custom exhaust job. Hmm... I think I'm unsold on that idea.


Tone,

Other than a high-flow air filter, are there any significant performance-enhancing mods you would recommend I do concurrently with the S/C install?

Zooper-Trooper said that the S/C kit uses the stock injectors, fuel pump, and fuel pressure regulator. I almost can't believe that the stock bits are capable of keeping up with the S/C! Is it really true?

[Cyrk]

Mine is going in for a larger fuel pump and a SAFC to hopefully tune the motor a bit since I have been running lean as of late and blew out my last muffler.

will have it dyno'd to see what else we can squeeze from it.

But yes the SC runs great with all the stock bits. About 75hp over stock with intake and some sorta of custom exhaust/muffler.

[Ascinder]

Yeah, you only really need higher flow injectors if you're doing some really serious boosting as I am sure any heavily modded WRX owner will tell you. For the amount of gain you'd be getting out of the supercharger, the stock injectors should be plenty. Once you run high boost(lots more air), an intercooler, etc. and are turning a couple hundred horespower more is when injectors come into play. I don't even think the transmission would be able to take that.