hey guys, just need some opinions.. looking to get either FI hi-flow cats or non-resonated test pipes but i heard test pipes r more for ppl with turbos.. and im obviously NA. what to doooo?!
thanks for the help!!

 

I'm so glad you asked this! I'm doing the same thing. 06 REV-UP, just put in the z-tube/ K & N filter, 5/16 MD iso spacer and MREV2 and thinking about whats next! I've heard good things about Crawford HFC's, but would really like to hear some input from the "authorities" on this one.

Also, will I have any problems running lean if I just bolt all this stuff on and reset the ECU? Or do I need a tune?

 

We've got some reading to do

 

I don't know why anyone would ever consider non-resonated test pipes.

I wouldn't be able to stand the smell from test pipes, so I went with FI HFCs.

 

does the check engine light come on, with this test pipes?

 

after 03.5 or 04.5 (forgot), yes. i wanna say it was after 04.5's that threw the light.

 

im prob. just gnna stick with the FI hi-flow's like i intended.

 

Any specific reason for getting the Fast Intentions? I've heard good things about FI, beck, and crawford... trying to decide which I should get!

 

Good customer service with FI. Can't speak for the others, though. May be just as good, I don't know. But Tony @ FI is very helpful.

 

Definitely something thats nice to have! Either way I've gotta wait to get paid before I even think about getting some LOL

 

First, I can tell you need a lot of research. Using our search feature appropriately will yield a lot of knowledge

To answer your question: Test pipes is just removing the OEM cats with a straight pipe. High flow cats are catalytic converters that are less restrictive than the OEM (think of it as "in-between" OEM and test pipes).

It is incorrect to assume that test pipes are just for people with turbo's. Test pipes yield great results with NA and F.I. But obviously you can get a lot more from F.I than NA

You have to consider the consequences of test pipes before you get them installed. Test pipes are much louder, will smell with fumes, and are illegal in any state. For some (like me), those are all plusses (except for the illegal part obviously). I like to squeeze every ounce of power my car has. And love the "raw" sound of test pipes. And the smell, I can live with it. Though it becomes a nuisance from time to time. And yes, you will most likely get a CEL light with test pipes (non-foulers can fix that, though not guaranteed).

High flow cats are more subtle in sound, won't smell, and should not throw a CEL. They will also not yield the same gains of power as test pipes.

If you go with test pipes, I recommend you go with resonated test pipes. They have a resonator to reduce the amount of rasp.

 

Connsider a full catback exhaust afterwards and then a tune. I have pretty much everything you have and also a Stillen intake (that one seems to not make much of a difference in power).

 

how much power can you get from HFC with the stock exhaust system

 

Research my friends! ^ ^ Skater broke it down for you basically. For HFCs, you have about 4-5 choices....Crawford, Berk, FI, Stillen and another brand I saw once on one of our vendor's sites.

I would check each site to see how much gains you should expect with HFCs. They biggest key here is going to be the tune you should get afterwards.

When you get the tune, you'll open up more gains because now your car's tuned to take the maximum effect with all of your mods together. Take a look at my mod list below.

One guy here in Chicago with just about the same mods made and additional 33HP this past week with an Osirus tune from Uprev! Look into all of these options.

As for me, I haven't done a tune yet because I want to go FI within the next year. I'm going to need a tune anyway when everything gets built. I figure why spend the money twice?

If I do get a tune I believe I can unlock an additional 25+HP with what I have now. I'm picking up a Fast Intensions Exhaust in the next week and getting a baseline dyno done on the 25th of this month.

I'll let you guys know how my car does in a few weeks..

bottom line....research my friends! Take your time....find the right deals. I went with HFCs because I have to go for emissions tests where I live plus I drive around with friends/family from time to time.

I have no check engine light and best of all, no one knows I even upgraded the cats because the car doesn't smell!

 

I went with Berk Metallic HFCs... After talking w/john @ Berk i discovered that they use the same spun metallic catalytic converter as FI. Also he indicated to me, w/several indepth emails, that metallic HFCs should only yield about 2-3HP vs TPs. If you look inside a metallic HFC you can see why. Unfortunately neither of the 2 companies sells the ceramics anymore, so they dont have the comparison picture anymore on their websites to compare the differences between the 2 media.

With the above said you need to ask yourself a couple questions.
*Are you wanting to squeeze out every last drop of HP you can?
*Are you willing to risk the Fix it Ticket for running test pipes?
*Are you ok with having a loud/smelly car which will attract good and bad attention?
*Are you aware that in some states it is no longer just a fix it ticket, but a fine as well?
*Are you ok with having exhaust sut accumilate on your back bumper?

Dont get me wrong. Resonated Test pipes are BAD ***. They give you the max HP and they sound deep and aggressive. But they have more downsides than up. I say, if you are a big enthusiast, have the capability of getting away with tickets and/or can change out your cats on your own, go with the resonated test pipes. But if you wanna stay safe, see some gains, have a deeper than stock exhaust, and not have to deal with all the downsides of TPs, go HFCs.

I chose to go with Berk, vs FI, because they are pretty much the same HFC (catalytic converter media comes from same source) and they are cheaper. Everyone back in the day said Crawford was the way to go, but from what i can remember, crawford had a knocking noise cause it rubbed somewhere and you had to bang a dent into the heat shield so it wouldnt touch anymore.

Keep in mind, among all the HFC companies out there, (considering they are all metallic HFCs, not ceramic) the real HP gains (dont compare their posted numbers to another's posted numbers) should only vary by about 1-2HP. So if you decide to go with a HFC, go with whichever you find a better deal on and feel is a good quality cat.

heres some links for comparison:
http://www.berktechnology.com/shop/p...cordPosition=1

http://www.fastintentions.com/exhaus...ti_default.htm

http://www.crawfordz.com/highflowcats.htm

http://www.kinetixracing.com/setpair...rg3503-06.aspx

http://www1.stillen.com/product.asp?...odel=G35%202DR