Well to start off I'll go by and list what I have done to my g37s coupe. I had gtm 2.5" catback with z1 teat pipes. Really good setup and sounds amazing. Also a Takeda intake, and tuning done by me...

Well I picked up some g35 obx long tube headers from a buddy with a g35 for $200. Pretty good deal right?. Well removing the stock headers by far was the worst thing ever. Passenger side wasn't so much of a hassle honestly came out and in goes the long tubes.. But man o man that driver side was a bxtch.. I removed some coolant lines on the driver side, undid the steering knuckle just to get the oem headers out, but when I came to put the driver side header... it would not go on at all cause of a aluminum frame on the bottom.. I had no other option but to cut the frame a tad bit to be able to get the header in. Well it helped a bit but still wasn't able to install it. So the next trick was to jack the engine up by loosening the motor mounts and raising it with a jack. Only this way was I able to install em.. well installed em and when I got to drop the motor. The header is stoll hiting something but it no longer the frame. It's a piece from the control arm so now the header/motor doesn't fully fall down and the header is rubbing up against the floor board and making a Lotta vibrations.

Exhaust wise. It sound great!!! A Lil exhaust here and there that I gotta get.fixed but it works. And I returned the as it made me run .5 leaner all around the rpm but mail in the higher rpms.

 

25hp??!!!

 

someone gained 16hp if i recall correctly...

im assuming the clearance issues were due to the fact that it was meant for a 35..

 

The issues were not that big of a problem it was too much I wouldn't of continued to put me on...

I shall upload a video on YouTube and post the link.

 

 

Rasp city

 

Most which come from the exhaust leaks on the flex pipes

 

Yeah, lifting the motor is almost always required for any V motor'd car getting headers installed. Then, hammering the tunnel a bit for fitment is also semi normal too. BUT, cutting the frame is not normal, they either weren't meant for the car or were built badly. Sucks man. But all in all, glad you got them in. The butt dyno tell ya anything?

 

The butt dyno actually felt pretty good you can easily feel how it outflows the oem headers and test pipes. It flows thru out the rpms a lot quicker that's for sure. This was before retuning it.

I datalogged a couple of wot pulls 1st gear and 3rd gear. To take a look at my air fuel ratio the long tube did make me run lean on the higher rpms when I usually run 13.0s I was running 13.6s. Did some adjusting on the map but didn't get to flash it to the car with the changes yet. I shall do it this weekend.

 

Oh nice, so you have a way to tune it? That's the only way to go with headers, otherwise, not worth the hassle at all.

 

Yeah I have the uprev tuner and usually do all my own tuning whenever I do any work to it. Have yet to actually take it to the dyno to see what it's pushing...

Next mod is probably to install the extra manifold I got I been boring out/ port matching.

 

Good work man. Glad there's still a few of us left that turn our own wrench. I see too many guys taking their car to the dealer doing basic things for huge $$$.. It's sad to see a car guy not doing car things.

 

Installing long tube headers on these cars is not "basic"...

 

I wouldn't say it's basic like he said. Cause it is a bitch to put me on... however I think it's more like.people don't wanna put their time and effort to do it.

It took me from 8:30 to 2:30 with a hour lunch break to install em.. rained at 3:00 then continued at 5 and finished conecting everything back up around 6sh.

One day spent doing this.. all it takes for your car to have some extra *****.

 

I am all up for doing work on my car, but some projects are just easier with the right tools (sometimes you have them sometimes you dont)..

As far as your project I respect your drive to put those headers on, but I wouldve bought the ones meant for G37s.