i beleive the cats are more of a choke pt than the headers.

 

Also, so adding headers/HFC will noticable add to this cars power given that I have 5/16 spacers, intake, and exhaust, correct? Just making sure I understand everything.

 

Unlike ISMSOLUTIONS, I think I can shed some light for you without trying to sell you any product. Before deciding to do any more engine mods, I was satisfied with my 5AT sedan having only a Weapon *R intake and a Stillen Gen1 exhaust. I then got bored and decided to squeeze some more power out of it, so I ordered TopSpeed headers (cheap @ $200ish, but welds, design, and quality is on par with the $600+ Alphawerks headers), Crawford high-flow cats, MREV2 & 5/16" spacer. The tone changed and the car sounded much meaner, but I wasn't really feeling the gains I had expected, and I knew just why, the ECU. The next day I bought a Unichip and went in for tuning- after a couple hours on the dyno, my car netted an increase of 29RWHP and 33RWTQ.

However, after driving around for a few months on this setup it feels weak to me. If you think that you're going to save yourself a few thousand dollars staying NA, you're probably wrong. You'll quickly grow to be used to the power is making and you'll once again be thinking about going FI.

I've since added a 3.5FD and modified my exhaust setup so I'm due for a retune, and I'll also be raising the rev-limiter to 7300RPM to take better advantage of my shorter gears. Then comes the Vortech.

 

i wasn't saying it was more of a choke point... just the first.

if you open up the first choke point, the second becomes a lot more important, and then the third, etc... that's all.

if you only open up the cats, you still suffer from the initial choke. do the two together and you on to something.

 

+1 on the crawford headers. That is what I am looking to do.

 

I don't suppose anyone really has the pipe dia/collector and outlet sizes of these headers? It would sure shed some light on why one is supposedly "better" than the other.

 

lol gotta love it

 

crawford's are longer, topspeed, pro-1, dc, strup, and a few others are equal length (as opposed to borla).

 

ive heard doing all the normal exhaust mods excluding the exhaust is a really good setup...supposedly the stock exhaust flows pretty good and adding in a TD or a larger pipe will cause a big low end power loss...99atlantic is running the I/H/HFC and says he has no power loss but all gain...anyone wanna shed some light on this...ive heard it many times and im in the process of purchasing a stock exhaust to try it out...

 

Nope - The only true equal length header is the Crawford.

Lou

 

bump

 

I have DC sports stainless steel headers which is what the alphaworks and topspeed/pro-1 headers clone from.

I also have the following:

Crawford cast plenum
Crawford high flow cats
Borla true dual exhaust
K&N Typhoon intake

Back in the day when I had nothing, my base dyno was 230HP, 222TRQ. Here is my most recent dynojet graph taken during hot Florida weather

 

http://www.aempower.com/ViewCategory.aspx?CategoryID=36
disagree. according to dc, they are equal length, if you'd like for me to verify with all of the other clones, i can, but i believe the only headers for our engines that are not equal length are the borla.

 

http://www.stillen.com/product_detail.aspx?sku=508350M
stillen's are equal too.
i'm having a hard time finding a more descript measurement of alphawerks, strup, and pro-1 (topspeed). but they are clones of each other (probably all made by the same chinese company).

the only one that appears different but i can't find more information on are the fujitsubo headers... they appear equal, but i don't want to assume anything.