OK another newbie question for the G37 S vets. I am able to spend $400-500 on an exhaust upgrade and I find that I could get either HFC's or an axle-back system such as Megan's. I'm in CA so I have to be able to pass the smog test every few years. My criteria are mellow sound without drone and performance. Recommendations would be most appreciated.

 

I could be wrong but I hear the hfc gives off a rotten egg smell when bought brand new id go axel back Megan racing is pretty much your only axel back for around the $500 range

 

Hfc> cheap catback

 

I'd look for a used CBE on here, HFC's just dont do it for me, Sorry,

 

If you want to stretch your money I have used Berk HFC for sale for $250 and I'm about to put up another classified for my used Invidia cat back for $450.

 

best? what are you wanting? i got 10whp with stillen hfc but ihad a stillen cbe already and other small stuff

 

I have a Tanable axle back and in my opinion it has the perfect sound.

I DON'T recommend a HFC, it will make your car's emissions worse (i.e. pollute more)

 

couldnt have said it better. I was in a similar situation and I chose the axle-back exhaust tanabe makes.youtube around for some sound clips of a stock g37 with the tanabe axleback and a stock g37 with HFC's. emissions and drone are usually associated with test pipes/hfc's. most people change their stock cats for improved airflow, not really for sound. if a nice low growl is what youre looking for I highly recommend tanabe's axleback setup.. its pricey so used is your best bet for the <$500 price range, but its definitely a completely new experience when driving the g around.. and I mean that in a good way.

 

it gives off a rotten egg smell because its new, its part of the break in and goes away.

your better off getting a complete cat back system which comes with ypipe, mid pipe, and exhaust muffler.

your going to want it later so might as well do it all at once.


I would go with a hfc over just a muffler change. just my 2 cents....

 

If you're looking for a performance improvement, then get HFCs over axleback. If you just want to improve on the sound, then I would suggest getting an axleback. Chances are if you go with just HFC you're going to get alot of rasp on the stock catback. And the sound will definitely not be mellow. I would jump on BB's Invidia catback if it's still available in the classifieds.

 

For Black Betty: Thanks for the opportunity but I think I'll go with Megan's axleback.

 

For All: Many thanks for your comments and recommendations. Think I'll go with the axle back. I did this with my CTS-V and it worked out great(along with a pro-tune).

 

Most power gain i got on my G with just Bolt-on was when i replaced cats with Resonated Test pipes about 20 more HP gain no joke (with tune of course) had Gemini Cat-back + Intakes tuned got me 298whp then few weeks later i installed the test pipes and then re-tuned it and ran it on the same dyno by the same tuner and got me 330whp i dunno what else increased my gains dramatically but i know cats were restricting my exhaust system way too much.. i'd say go intake & Tests/HFCs then exhaust i hear people getting 310s with factory exhaust

 

Cats are the most restrictive part of your exhaust and a **** catback like megan is not even worth gettting, your going to regret it and want a diff catback later on!

 

I have Fast Intentions resonated HFCs with the stock catback system and I love them. Nice power and sound improvement for half the price of a full catback exhaust. I don't have any rasp or exhaust smell. At $400-500 you don't have enough for a quality hfc or exhaust system...imo you should save up a little more and get a quality part.

Do some research...most people on this board are very pleased with the FI RHFCs but they'll cost you around $620. Berk HFCs are cheaper but you'll get more rasp from them. Some recommemd test pipes rather than HFCs but thest pipes will give you more exhaust smell.