"Cold Air" Cosmo SRI setupway

[rxm6]

For the past month or so I've been watching my gas mileage consistently stay below 20mpg and my performance slowly get worse as the car heats up. I finally decided to do something about it.

I was fairly certain it had something to do with my intake due to the fact that A) at 6:30 in the morning right when I start up my car and accelerate down the street, the performance was pleasing B) as the car warmed up that pleasing feeling went away, and C) My gas mileage was pretty bad.

Here is my original setup that Cosmo racing sold me:



Removal of the stock intake system really opens up the compartment and lets a lot of air swirl around in there. The problem with that is that all that air is coming right through the radiator and into your intake. A log of the air intake temp sensor revealed that 132F air was being sucked into the engine at standing idle!! So with my trusty laptop logging software booted up and ready to go, I set off to create a colder SRI.

**By the way, all these tests were performed at approximately 63F at sea level.**

As I said before, standing idle showed intake temperatures at 132F. At a steady speed of 45mph the intake temp dropped to 108.9F. And after a standing idle of 20 seconds, the intake rose to 115F. Not good.

I've seen a lot of guys on here take off the top of their air intake box and stick a filter there. So I tried this with my Cosmo:

Tests showed a 10F decrease in standing idle temp to 122F. Also a small decrease in the steady 45mph test to 105F. Still poor, but getting better.

I noticed in doing these tests and trying to figure out how to make my intake better that the metal tubing of the intake was getting extremely hot because the radiator fan was blowing air directly on it. So I wrapped it in heat wrap. Also, I noticed that most of the heat was coming from over the top of the battery and resulting in such a hot air intake temp. I was determined to get my SRI cooler.

The 3rd evolution of my design yielded the greatest gains and is what sits in my car now. In approximately 63F weather at a steady 45 mph I was recording air intake temperatures of 68F! Also, I've noted a substantial difference in the power of the car, however, I have no data to back me up on that. One other interesting thing that I noted was that at 45 mph with cooler air, the rpms dropped from 1600 to 1550. Not sure that makes to much of a difference, but something worth noting. Here are pictures of my final setup:






Modified by rxm6 at 10:33 PM 9/23/2007

[MinisterofDOOM]

[g35cuhlean]

dang, i was thinkin about a short ramp, but now i am not going to do that no more. Thanks for the input. I am just going to get a tint and later on som rims and drop it like its hot.

[xerexabante]

i sent this write up to a guy at g35 forum, and changed his mind. this would be a good sticky.

[rxm6]

HAHA...in a way I didn't intend this to dissuade people from getting a short-ram. I just noticed a loss in power and gas mileage and decided to do something about it. The only really good CAI intakes are the ones that go inside the front fender that you have to drill a hole in the car for. Everything else is a just a WAI. I meant this to be more of a write up for people who bought the short-ram already and didn't feel like spending 200+ on the CAI system or drilling a hole in their car.

[NewfoundlandDude]

What was your gas mileage looking like after the setup?

I have a CosmoRacing SRI, but as you can see from the Sig, I think they just sent me the first section of their CAI (WAI).

It was a pain to get in, and the connections sit at about a 45 degree angle inside each silicon connector, so I don't think I'll be able to mimic your design

[rxm6]

I got an additional 38 miles out of my tank of gas. So, now with the synthetic oil and the cooler air I'm running about 380 per tank which comes out to about an average of 23 mpg. That isn't bad considering I drive in a "spirited" fashion. I have no doubt though that I could drive to LA on one tank of gas.

Also, for your Cosmo, why couldn't you get a sheet of plastic and place it in front of the intake to divert that hot air from the radiator. I'd have to think about it some more but thats all I can think of right now.

[Sentientbydesign]

How is 380 miles/tank equate to 23 mpg??? Our tanks hold over 17 gallons (18.5 is the spec, but I've never filled up more than 17.6).

[rxm6]

How is 380 miles/tank equate to 23 mpg??? Our tanks hold over 17 gallons (18.5 is the spec, but I've never filled up more than 17.6).

Because I never fill up 17.6. Every time I fill up its around 16 gallons...so I'm reporting my tank as 16 gallons at 380 miles. If I drained my tank to the last drop I could report perhaps a higher figure, but I never drain my tank.

[Ryan Heo]

How come you can go to 380 miles per full tank.My 96' I30 is 250 miles per 16 gal even though it doesn't have any check engine light, all new O2 sensors, and it is feeded up shell premium only.Thanks.

[xerexabante]

question what size is your tires and rims?

[rxm6]

question what size is your tires and rims?

I have the stock Infiniti touring wheels that are 16x6.5 aluminum alloy with 215/55-16's

How come you can go to 380 miles per full tank.My 96' I30 is 250 miles per 16 gal even though it doesn't have any check engine light, all new O2 sensors, and it is feeded up shell premium only.

1) Every oil change (5000 miles) I add injector cleaner to my gas tank.2) As a rule, I never use Shell gasoline. Every Porsche I ever worked on that used Shell gasoline had injector and filter problems (especially the older ones)3) Your knock sensor is probably bad and it won't throw a code. Mine was bad and I was getting 280 miles per tank.4) I take turns at high rates of speed and conserve momentum

[MattB]

How come you can go to 380 miles per full tank.My 96' I30 is 250 miles per 16 gal even though it doesn't have any check engine light, all new O2 sensors, and it is feeded up shell premium only.Thanks.

Check your knock sensor. Also, when was the last time the car had a tuneup and air filter change? My I30 gets about 25-26mpg in mixed driving. I've never had any problems with Shell V-power gas though. I run Sunoco 94 octane when I can find it but otherwise my car gets Shell premium.

[Beancooker]

Sweet article. Makes me think about wrapping my intake.

[Beancooker]

I did the same tests on my G35. The results were similar. This was an awesome idea, and thanks for getting me started on it!

zerothread/282618

[rxm6]

I did the same tests on my G35. The results were similar. This was an awesome idea, and thanks for getting me started on it!

zerothread/282618

Thanks! I think I will try to post this on my website if anyone else wants to look at it in the future.

[balplayer91]

where can you buy heat wrap? do i have to order it, or can i just buy it at a store??