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Starting the build thread for my 2009 G37XS. I eventually started to look at some Gs on FB marketplace and gave up after about 2 months of looking. One morning before work in December I spotted the XS for a good deal and low miles. 14k for 47xxx miles and it already had a fast intentions catback exhaust on it. (I didn’t know any of the infinity aftermarket brands when buying this car.) I ended up writing a check for 13k and then sold my Chevy for 9k a few days later. Time to start with the mods! 😎 first mod was a set of BC coilovers lol.
BC Coils took me and my friend like 5 hours to install. We got done around 2 am on a Wednesday and then 2 days later we got 2 feet of snow. Let’s just say I was literally plowing the driveway with my slammed awd car 😂. Next was adding my sub. 12” kicker LT7 square sup paired with a 600w JBL amp. (The stock Bose sub was not doing it for me lol)
Manually wired in an RCA cable from the Bose amp for the factory sub. Ran my remote wire from the fuse box under the steering wheel using the cigarette lighter fuse. Power wire was ran down the passenger side and wasn’t too hard to hide and get through the firewall. It was a major upgrade from the Bose sub, and then some more snow. Test pipes are next.
Test pipes were on the list but they were expensive, so I went the DIY route. I purchased some cheap eBay test pipes and some cheap Amazon resonators, and then brushed up on my welding skills. Taking off the stock cats was rough. First bolt i tried I stripped. Took a trip to harbor freight for some extractor sockets and they did the trick. Also switched to using all 1/2 inch sockets and extensions and this helped a lot. Ended getting all the demon bolts off. After that the install went smoothly and took less time than the coilovers. One side was a bit tight and I didn’t have it exactly straight with the rest of the exhaust so it was a little difficult to tighten. They sounded great, but had some issues with the bolts coming loose. This was my fix.
welded in a little flange so I could use the oem gasket and also got some locking nuts. Fixed the issue and doesn’t seem to be leaking. Now that the exhaust was done it was fine to focus on the intake side of things. Opted for some K&N drop in filters first. After uncovering a 2007g35HR at a local salvage yard I took the upper intake manifold. I had read that they were the same as the motordyne m370 and made good power. This manifold was cheap so I went for the project of making it work on the 3.7. After some fabrication and drill press work we got the holes drilled. After that it was to the hardware store for some hosing and brass T fittings.
Did a little smoothing of the molding flash. Some runners seemed to be much worse than others. After that we installed it and all seemed to run correctly. Didn’t feel much of a difference after the install. I think the car needed to adjust to the new air flow. It eventually felt a bit more punchy through the midrange but not a crazy amount. I was debating purchasing a long tube CAI but after seeing some dyno results I opted to stay with the stock airboxes as they are designed very well. After the drop in filters there doesn’t seem to be much gain with CAI or 3 inch intakes, so I didn’t think it was worth the money. Although they look really good 😎
I went with the budget friendly Megan racing strut bar. Sprayed some black spray paint and used my fiber laser at work to make an OEM+ looking bar. Early on I purchased some used Akebono sport brakes off of a 2016 Q50 a while back and they sat on the shelf for a month or so.
After finally deciding to not spend $700 on 2 piece rotors I find a good deal for some used rotors. I sprayed them with cerakote and got them re surfaced. Turned out good IMO. FYI I didn’t expierence any significant decrease in 0-60 times with the added rotating max from the heavy a$& rotors. As that’s why I was wanting the 2 piece ones. This was the mod I was most excited for as I always wanted a car with big brakes. Adding the SS lines and EBC yellow pads I was very impressed with the brake setup. Other that the dust… holy crap. Don’t buy yellow stuff pads unless you have black wheels 😂. A set of soft surfboard racks were high on my list as I surf regularly here on the Great Lakes.
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Last edited by Josh South; Sep 25, 2023 at 03:50 PM.
Wheels were next so I could actually see those big brakes I spent so much money on. Wheels were my next big purchase and really didn’t want to cheap out on them. Luckily the ole G35 sport came with some 19’ forged Rays and nobody wants to keep them. Found a decent set for $400 on FB and picked em up. They were just beat up enough I wanted to re finish them but also could pass on the car as is. After some pondering I decided to re finish them using some air cure cerakote. After renting out an industrial sand blaster and 2 hours of that I had some wheels ready for some color. I went with a gun metal gray as it was very close to my cars paint color. I saw a gray BMW with matching wheels and really liked it. This is how they turned out wrapped them with Firestone fire hawk as V2 rubbers. Paired the wheels with 20mm spacers in front and 15mm in the rear. I’m happy with the fitment. Had the raise the rear a few MM. -
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Next was the tune… oh the tune. After calling a few shops in my area I could not find one that was willing to tune my car that also had an AWD dyno. I went with the Z1 remote tune. It was pretty simple and easy to install everything and the ecuteck app is very user friendly. Started doing some data logging. After 14 3rd gear pulls to rev limiter and 7 maps my car was now slower than it was stock… 😂my car was doing 14 second 1/4 miles LOL. 6 second 0-60s. After some back and forth with the tuner we decided to blame it on bad gas and start with some new maps. After 2 revised tunes my car was back to doing a 5 to 5.3 second 0-60 as before the tune. I didn’t really gain any on my times but the car seems to be running smooth as a watch. I can notice the car really pulls hard and feels pretty quick. I talked to Admin tuning and he flat out told me “the Z1 remote tune is garbage, buy ours and I will turn you up.” Ha so I currently am sticking with the z1 tune as the car feels good and I would rather be on the safe side with reliability. I also have heard admin disables the knock sensors and that’s why he gets a lot of power.? Just something I heard lol. So this is how I’m sitting as of now. 😎
New test pipes and front rotors. Modified my Takeda intakes by cutting out the necked down section and replacing it with larger 2.75 pipe and re welded with the MAF sensors. Then re tuned. This combo seems to work really well with the G35HR manifold. Going to do injectors and re tune for E85 next.
Did you just buy that black sedan? Spill it, Josh.
That's some crazy looking shift ****.
I bought it on Sunday! The driveway is starting to look like an Infiniti dealership LOL
I wanted a manual from the get-go but I could not find one. I've been looking for a 6mt sedan for over a year and a half and one finally popped up within my price range! Time to sell the g37xs.
I bought it on Sunday! The driveway is starting to look like an Infiniti dealership LOL
I wanted a manual from the get-go but I could not find one. I've been looking for a 6mt sedan for over a year and a half and one finally popped up within my price range! Time to sell the g37xs.
That's fantastic. Congrats! There's a lot of things you can do with the 6MT that you wouldn't with the AWD.
Start a new build thread right now while you're in the moment.
