Sorry, if this has been asked before.

I checked the Stillen headers and hfcs for 370Z, and they are the same part # as for 350Z HR. So in theory, for example, 370Z Fast Intentions long tube headers should fit 350Z HR, correct?

Has anyone done this?

 

I have been wondering about that myself. Looking over a couple 370z install pics, I don't see why not. Performance Motorsports has installed these, I'll have to ask them this week while I am down there.

 

Try it and let us know how it works out.

 

I actually asked FI the exact same question about a week ago. Here's their reply:

I did an install on an HR 350 here in the shop a while back. They fit 95%
correctly. I had a few issues with some minor things. If you are
interested, please give me a call and I can walk you through what you would
need to do to make them fit...

Thank you,

Tony Meyerson
Vice President
Fast Intentions Inc.
8725 Canby Ave.
Northridge, Ca. 91325
T: (818) 882-2788
F: (818) 882-2834
www.fastintentions.com
tony@fastintentions.com



-----Original Message-----
From: ***** [mailto:*********@gmail.com]
Sent: Friday, May 06, 2011 6:09 PM
To: Tony&Dan
Subject: Inquiry from Fast Intentions

Will your long tubes for the 370z fit a 2007 350z HR?

 

Going for 350 NA hp?

Is that where you got your dyno done? I would love to go there to get me a 300whp dyno sheet and frame it

 

Also, you're mixing way too many variables in your question....Not only are you talking two different manufacturers, you're talking shorty+HFC combo vs long-tube. Yes, the headers are going to start and end at the same place, but how the piping runs could be drastically different. The steering rack seems to be the area with the most clearance trouble.

 

Anything is possible! All it takes is alittle money! Maybe someday you will be amongst the 300-500 WHP club. Whether it be NA or FI.

When again will you crack open your piggy bank for some upgrades? Still rawkin that DE block are you>?

Zim

 

yup still got the DE. Kinda weird iv never been beat by a HR. I guess the saying is right driver wins races not always the car. Whats your quarter mile times? over 300whp should net u high 12s at least thats judging by all the "mods" in your sig.....

 

95%? Did you happen to find out what were other minor issues?

 

here's my dyno with megan racing long tube headers on the DE (its the green graph run #3)

 

this is for a HR. However very interesting graph

 

I would love to know where the differences are as well. I know the Stillen headers had issues with hitting the steering rack when they first came out because they were designed on a 370Z. Hopefully we get an answer because I'm getting the Stillen headers and GTM resonated test pipes soon and these headers would be another option to look at.

 

Was it tuned after the headers? Was the car stock except for the headers? You have to be careful when looking at before/after dynos on cars that are both untuned AND have other mods.

Cars only run so rich from the factory. If you lean out the car with an intake, plenum, and exhaust, there may not be enough fuel left on the oem maps for the extra airflow that the headers provide. Conversely, if the ONLY mod to a bone stock car is headers, you could potentially see a greater gain than in the first example, b/c the car is running rich and you know there's sufficient extra fuel there to accommodate the new mod.

Anyways, it's more complicated than that, and can vary from car to car. I'm just saying that a dyno is just like statistics -- you can make it say whatever you want by pulling it out of context.

 

No...I was in Philly at the time and just haven't gotten around to it. You know you can always email them directly like I did

 

I E-mailed Tony about the 5% issues, I haven't heard back yet but when I do I will post up here and let you guys know what he says.

 

^Thanks, please do.

 

Steering rack is in a different spot, cam profiles are different, heads are different, intake manifolds different. These all affect header design.

Fitting and be a correct design are 2 totally different things

I dont know anything about these but nevertheless, Long tube doesn't mean better - just means long tube.

 

Honestly! The HR headers are already equilength, or at least close to it. Save your time and money and just get some test pipes. I am willing to bet that not even 5 whp (if that..) could be gained from aftermarket headers on HR 350Z's. Please correct me if I'm wrong though with a dyno graph..

 

Proof that you would lose power please? The headers that came off my HR didn't look very equal in length, they were made of a different metal, and the 'base' that connects to the engine was significantly longer allowing for longer tubes. Plus equal length does not mean 'same length as stock' right? It just means equal with itself.

Not hating though, honestly just trying to justify me spending all that money really...

 

Well I don't think they'd lose power, my bad. But I don't think they will gain much either. Sorry, but I'm just saying they aren't worth the money especially with how big of a pain they are to install.

Usually people replace headers to get equal length tubing which I guess increases scavenging or something.. I am no expert to headers though. Anyways you can compare the DE headers to HR headers to your aftermarket ones and tell me what you think. I'm going to go out on a limb and assume that all of the tubing sizes are about identical, the only place I could imagine any positive gains would be in the collector area at the end of the individual tubes, but it looks pretty decent on the HR headers from what I can see. But like I said, I have yet to see any dynos comparing stock HR headers to aftermarket..

http://www.*********.com/wiki/images/c/c0/VQ35DE-1.jpg

http://www.*********.com/wiki/images...-Engine-19.jpg

http://www.stillen.com/image.asp?/pr...es/508385C.jpg

Wow, lame. Replace the **** with 3 5 0 z - t e c h (without the spaces) to see the images.