I am thinking to upgrade using Stillen header and exhaust. How much power should I expect to get? Will I be able to feel any difference? Will this give me the same performance as the current 3.5HR engine in the new G35? Links below.

http://www.stillen.com/product.asp?i...odel=G35%204DR

http://www.stillen.com/product.asp?i...odel=G35%204DR

 

No. Not even close. You probably need to spend almost 2k+ to get near the HR.

 

after the headers, you are going to want to tune. my last vq went from 13.s with regard to the air/fuel to high 11 after headers. obviously each car reacts differently but id suggest some sort of flash or piggyback to tune it after headers. at the minimum, get some pulls on a dyno with a/f monitoring to see its state.

 

You'll get little to no improvement from the headers unless you open up the restriction in the stock cats then follow up with an ECU tune as you'll most likely be running a little lean. Get a set of high flow cats, your ECU tuned and that'll be what really gives you the power you're looking for.

What are you running on the intake side? If you're stock, K&N drop in filter, z-tube and a plenum spacer will do a lot for you as well. You need end to end bolt-ons with a proper tune to really come close to the HR. If you have the 6MT w/ the 298 hp engine, get the MREV+ with the modified lower collector.

For the money you'd spend on headers and install, you can substitute high flow cats, plenum spacer and z-tube and get more of a gain than just headers alone. Headers are more labor involved whereas everything else I mentioned can be an easy DIY or relatively quick at a shop. I'd still recommend doing headers if its in your budget, but I'd sub in the other mods instead of headers if you're on a budget.

 

I agree 100% be sure to get a piggy back system of some type.

-Sean

 

If that is the case, the following might be considered as an option.

https://g35driver.com/forums/tuner-dyno/162472-need-tune-no-more-mail-required.html

http://www.my350z.com/forum/showthread.php?t=279548

 

That is pretty cool - i haven't heard about that one...i would like to try it out, but i don't know how it would work out with my AFC controller.

-Sean

 

Yeah, once I finish my engine oil consumption test, I am going to check it out for myself.

Edit: Give them a shout. they appear to be very helpful and knowledgeable.

 

It all depends on your current setup. If you are bone stock, headers are almost completely useless as the stock cats, which are very restrictive, will not allow the extra flow of the aftermarket headers.

You can do both just fine, but make sure you add HFC to your list. Before or after, it doesnt matter. Just get them!

For a whole exhaust system (exhaust, cats, headers), I would highly recommend a tune. After the tune, I would guess you just added anywhere from 10-20 rwhp & 15-20 rwTQ. These are optimistic guesses though.

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