i know the test pipes/hfc from 370z are same fitment/interchange with HR 350z. Question is what about the aftermarket headers. Stillen site lists the same part # for HR 350z and 370z so the "should" be direct bolt ons right?

 

It should be, can't find it but they is a guy on this board that put the oem 370z headers right on his hr, no prob.

 

Quick Q: Are the OEM 370z headers any better than the 350Z HR headers?

 

I think it's crazy people work so hard to make their car perform worse.

 

I think you mean the 350Z (VQ35HR) test pipes/HFC fit the 370Z... They were made for the HR and then people figured out they were interchangeable.
Please explain your logic/knowledge behind your comment.

 

Following the logic of installing OEM 370 headers on 350 = gains makes no sense to me. At best you'll be sitting par after all that work. Unless you're missing 350 HR headers and only have a set of 370 headers laying around, it's a waste. Just because the headers are off a slightly larger displacement engine doesn't mean they are better for your application.

I am of the opinion that OEM headers are better than most aftermarket pipes for our applications and this is coming from someone with a set of Stillen headers/HFC's installed.

Just my .02.

 

Ahhhhh, I see what you mean now. I thought you were talking in general, mod wise.

I would like to see the 370Z exhaust manifolds/headers next to the 07-08 350Z exhaust manifolds/headers. I wonder how they compare in size & design.

 

The engine in the 370z sits lower then in the 350z. The headers and/or the cats are longer on the 350z then the 370z because of the lower engine fitment.

 

They also fit the DE and are available with heat shields for 300.

 

Well then you obviously have little to no real experience with dyno tuning various set ups with and without aftermarket exhausts and headers. It is a fact that the equal length tubular headers on the 370 flow better than those on the 35DE/HR, (more so DE) despite what you have on your car. When it comes to the 1/4 mile the extra 3-5hp and 2lbs of TQ give or take over stock manifolds here and there while tuning add up.

 

Not the HR comparison you asked for but will help anyone with a DE that's curious.

http://i.ebayimg.com/t/VQ35DE-OEM-Ex...,!9Mw~~_12.JPG

DE http://www.z1motorsports.com/350_g35...309&imageNum=1

 

Just because yours does.

 

I just bought (for nearly nothing) a set of stock 370z exhaust manifolds. I am going to install them on my de 350z I have test pipes and figure I can just cut and re weld them to fit. I understand my gains will be little to none but honestly don't care, its part of my finishing touches. When I get them Ill take some pics, in the mean time if you look at the
stock de mani's


Compared to the stock 370 manifolds


Then Nismo 350z R tune headers


You can see that I hope for good mid power gains.

 

I think the head flange is different between a DE and HR,370z. I think a stud has to be modified.

 

Yes one of the studs must move.

 

I noticed a difference between stock and crawford headers on my DE motor, but my headers only cost $20 new

 

There is a photo out on the net I saw ones on how to put tomi de headers on a hr. Its one bolt you need to switch rather then putting it on the bottom you put it on top. Can't remember the site ****

 

soooo blast from 8 years ago seems all that's needed is a stud removal..? About to hit confirm and pay on OBX headers for my 370

 

you will have to change cats if you change to the different header.

 

True, (unless he's 1 of those daredevils running test pipes) plus a new tune.