Ok folks, looking for some advice/recommendations here. Going to install some headers from a 08 350Z on my 03 G35 Coupe. After doing some research, I know its a PITA. I have use of a lift and all the needed tools. I'm looking for some recommendations to make the job a little easier. Additionally, I'll be replacing the entire exhaust system: 08 350z headers, 07/08 350z OEM CATS or Stillen HFC's, 07 350z HR Y-pipe, and a stillen single pathway catback exhaust. I have everything except the CATS. Any help would be greatly appreciated.

Thanks,

Terry

 

i don't think those headers will even fit on your g35.

 

you need an extender because your g35 exhaust is longer than the z's.

 

Take a look at this thread: http://g35driver.com/forums/intake-e...-2003-g35.html

 

what does that have to do with anything?

quick question, what do you think you will accomplish with all of this?

 

Should work as long as I have 07/08 HR OEM CATS or HFC for 07/08 350Z.

 

Freer flowing exhaust. OEM Headers off the 07/08 350z are a hell of alot cheaper than the after market ones. Understand HP gains will be minimal. Trying to find as much free HP as possible. Did you read the entire thread? Nissan made changes to those parts for a reason. Better performance/efficiency for the VQ. DaveB may have stumbled on to something. Never hurts to upgrade the older VQ's and not kill my pocket book.

 

Headers from an 08' definitely won't fit on your 03'. You're right when you say Nissan changed these parts for a reason. ...It was to fit the new HR heads.

As for the Y pipe, if you can find one cheap enough give it a shot. It's an easy swap.

 

Keep us abreast of the project with photos. Thanks.

 

+1

 

It's obvious the OP has put in some decent research on this idea. DE headers can fit the HR so long as the DE TP/HFC are used. It's not that far of a stretch to assume the opposite. If you go along with it, you really should take pics and post up results, whether success or failure.

TK

 

If you read the thread that I posted from DaveB, he's done the research and they will fit. I've already changed the y-pipe and air box, both off an 07 350z. I'll keep you all posted with a write up and pic's. Like I said earlier, any advice will be greatly appreciated...

 

I could be wrong . I will say this though, doing the research and doing the swap are two completely different things. If I am wrong, that's awesome because then people have more options. If I was right though and you take the car apart and they don't fit that will really suck.

My advice: buy a set of 03' header gaskets for your engine and see if they match up to the new headers or confirm his findings on your own through a separate credible source before taking it apart. If you look at the pictures he posted the bolt pattern is different for the two. It may just be that the HR headers use less bolts to mount up (that could be why the gaskets have different part #'s). Either way, I'd want to be absolutely positive before diving in.

Do keep us posted though because I'm curious to find out.

 

Looks like its missing two holes. I'll get a set of gaskets tomorrow and let you know.

 

https://my350z.com/forum/vq35hr/3485...ders-hr-2.html

See post #22. Apparently Shariff at Forged as test fit DE headers on an HR as well.

 

ok, as suggested, i purchased an exhaust manifold gasket for the a 03 VQ35DE and match it to the 08 350Z headers. It matches up perfectly. The 08 headers will require 2 additional holes drilled in the center flange. The 08 header has 6 bolt holes (2 on each end/2 in the center) whereas the 03 exhaust manifold has 8 (2 on each end/4 in the center). There's plenty of room on the flange to drill the additional holes. I went to my local nissan dealer to purchase the gasket...$59.00..F that..Auto Zone sold a pair of FEL-PRO gaskets for $9.00. Wonder what the infiniti dealership charges?? Will try and get the headers installed over the holidays.

 

Finally found a set of 08 350Z headers. Will start the install shortly. For you folks who want to save a couple of bucks, here is what I've spent so far:

08 350z Headers: 120.00
08 350Z Cats: 200.00
Gaskets/misc parts: 75.00
Total: 395.00

Did a comparison with some after market parts:

DC Headers: 769.00
Stillen Cats: 515.00
Total: 1284.00

Total Savings: 889.00

Definitely not cracking on the after market parts, but if I can get the same performance out of OEM parts and save a few bucks for other things, why not!! I'll keep you posted.

 

I think I'd go with aftermarket STAINLESS if you're gonna go to that much trouble... Unless the OEM happens to be stainless - Which it ain't.

 

Only looking at it from a economics stand point...If this works, then its another option for others to think about...

 

Is this really saving? or wasting?
Why don't you just get a nice hfc or RTP ?