Putting On K&n Directly On Mass Air

[rustyruststang5]

I put a k&n filter on the end of my mass air meter on my 1988 mustang, the mass air meter is a stock one off of a 90's stang. Well since I put it on some times the car will idle rough and it runs a lot leaner than it used to when I just drive normal. I have an aem wide band to measure a/f ratios. When I get on the gas it does go rich like it should. I’m looking at this one bbk makes and it pretty much the same so I don’t know why I’m having problems with doing this modification

 

[88LX5.Oh]

You mounted it like this?
Jrich (IIRC) has a post that says when an air filter is mounted like this, it'll sometimes get HOT air coming into the filter and cause idle issues. I'd say fab up a little heat shield or do an in-fender CAI.

 

[jrichker]

Mounting the air filter so that it picks up air from inside the engine compartment is a bad idea. The stock airbox and a flat panel filter is the best solution for almost any combination. If you don't use a the stock airbox and filter, the air still needs to picked up inside the fenderwell, not the engine compartment.

 

[MFE92]

Yup...filter mounted like that actually cost me time at the drag strip as the car warmed up. It won't show up on the dyno thanks to open hoods and massive fans in front of the car, but out there in the real world, it's a performance killer. That said, heat isn't the source of the idle problems with the filter mounted that way, supposedly the radiator fan airflow is. Bottom line is, move the filter to the fender, shield it, or just put the box back in with a panel filter. No performance penalty for that vs cone filter in the fender, unless you're making huge power.

 

[rustyruststang5]

thanks guys all just take the k&n back then

 

[Exile]

If you just need something cheap I would suggest one of these.

Fenderwell Cold Air Intake - $60
http://www.americanmuscle.com/50liairinkit.html

Fenderwell Cold Air Intake - $70
http://www.latemodelrestoration.com/item/LRS-9659CA3/Mustang-50L-Clear-Anodized-Economy-Cold-Air-Kit

 

[Ufg062003]

There isToo much fan wash, caused erratic idle on mine, I reverted back to stock box removed silencer and installed k&n panel, runs way better

 

[ReefBlueHatch]

I'd pass on using an aftermarket CAI. I had one on my car and what a piece of crap - fit horribly and looked tacky, IMO. Accessing to remove and install the filter was a huge PITA. I picked up a stock box and tube setup and couldn't be happier. Also it's all plastic and rubber, so less heat soak.

 

[88LX5.Oh]

You guys are making me wish I didn't junk my stock air box
I may just end up making a heat shield for it.