Thread: Subaru question. Dumping torque and HP

Yes this isn't a dsm but this is a common question and it goes a little somethin like this. On my intercooled subaru I had a k&n style cone filter originally and the car would pull hard throughout the rpm range. Now I am running an air filter with a heat shield on it and the car is dumping torque midrange through the rpm band. Bottom end torque is explosive but the power is pretty much gone by 4000 rpms....... My assumption is that my heat shield air filter is too restrictive compared to the other one. I just wanted to ask some of the vets what their opinion of heat shield air filters are. I think its probably pointless to run one when I already have an intercooler. Can I get confirmation on that or somethin?

That was my first thought also. You're pulling cooler air but a lot less of it. When the engine is turning slower you're pulling enough air to fill the cylinders and make some power. If you had some sort of logging abilitity, you'd probably see airflow per rev drop off where you're feeling power loss.

Originally Posted by 98spydert

That was my first thought also. You're pulling cooler air but a lot less of it. When the engine is turning slower you're pulling enough air to fill the cylinders and make some power. If you had some sort of logging abilitity, you'd probably see airflow per rev drop off where you're feeling power loss.

I already have a scoop bringing a decent amount of cool air down. As for logging capability, none of the traditional stuff will work with my car, no logger obd cable around, I'd have to log strictly off of egt and a/f ratio. I'm open to ideas though. I think its much more restrictive on the heat shield than on the other cone filter I had. I might just cut a hole where the stock airbox was and let the car get some air from inside the fender and wheel well.

What's your wide band say around the rpm you loose power?

Originally Posted by 98spydert

What's your wide band say around the rpm you loose power?

Don't have wideband or egt, I was just saying that about all my car can use. Theres a subaru equivalent to dsmlink called megasquirt (yes subi guys are weird), but my engine and years don't work with that setup.....The gen before and after do, sucks.

Got this problem fixed, I had a bad intercooler to tb connector. Replaced it today with a silicon coupler from tognottis, RPM band is nice and solid and car is pulling great.