JWT CAI Install and other antics.
There are various "cold air intakes" on the market for the Murano/Altima now, and being that I could never resist "improving" any car I've ever owned I knew it would not be long until I would need to have one. There are several on the market, but I finally settled on the unit from Jim Wolf Technologies (JWT) because their design looked simple and well made, was CARB legal, and they have such a good reputation in the 300ZX community. Another deciding factor was the excellent install guide and review over at Nissan Performance Magazine, and their dyno numbers showed that substantial power was available to be had. While list is $159.00 I was able to pick it up for a song from nissanparts4less.com for just $99 shipped, the only minor issue being that they are backordered and it took almost 3 weeks to arrive.If you can bang two rocks together you can do this install, it really isn't rocket science at all, a 10mm wrench, phillips screwdriver, and about 45 minutes was all I needed, and that was doing the procedure slow and careful. Sound at idle, cruise (both streets & freeway speeds), and gentle (2KRPM peak) acceleration is identical to stock. Nudge it up to 2500RPM and it starts to growl a bit, but get on the throttle hard and wheheee!!!! From 3K RPM up it's, urm, um, a wee bit louder and it sounds great. From 5K to redline the engine is one screaming angry VQ35 =). Check out this 2MB video to hear what it sounds like.
As you can see in that video, on my G-Tech Pro Comp the initial dyno numbers were very disappointing. That's 13WHP *lower* than my previous run on the same road in similar weather. Multiple runs confirmed this, and my 0-60 time went from the previous great stock time of 7.2 seconds to over 8.
It's been said that many great insights and inventions in human history have been thought of in the shower, and such did NOT happen here. No, later that night what came to me in the shower was that I was a pure idiot and had forgotten I had loaded the Mo up with a tank of 87 octane. Doh!!! But could that really account for all of the huge loss? The next day with a quarter tank left, I hit a special 76 station near me and added 5 gallons of 100 octane and then topped the rest of the tank off with 91 to sweeten the brew.
That night, again cold and clear in the mid 50s, I went and weighed the Mo again (it had gained 80 lbs worth of fuel, need to make sure the G-Tech knows that to calculate it's numbers properly) and hit my special 'strip' near San Jose International airport. *MUCH* better! 6.5HP and 6.1 lb-ft of torque over stock at the wheels, which roughly translates to 10 at the crank, and a full 20WHP more than with 87 octane, most of the improvement coming from 4K RPM to Redline. That is DAMN good for a simple CAI, which more than anything shows how cheap Nissan's intake design was on the Murano & Altima compared to the 350Z and G35 which sees far less (if not none at all) improvement from a CAI.
Here's what the numbers look like, the Main Run is with the CAI, Run 1 is with CAI & 87 octane, and Run 2 is Stock:
If you would like the raw numbers to play with, here's CSV files of Stock and CAI.
While the motor does sound great now when I get on it hard, it's a little unbalanced...The CVT whine and CAI sing in harmony but the exhaust is totally missing from the chorus, so next on the upgrade parade is ditching that sorry mid-muffler for improved ground clearance, sound, and hopefully performance.
