When I start my car in the morning, let it warm up a minute, then drive it...my engine feels strong. But then after driving it for a while after it has reached normal Operating temperature, it kinda feels like I lost a couple horses. It still feels strong, but like it just lost that little 'edge' if that makes sense.

The intake i have on is a ****-e generic one, that I am using for the meantime until I get something better. It is a pretty short ram style one. Once the engine bay has gotten warm , would I be right in thinking that the very slight loss in power I feel is because of the warmer air being sucked in through that intake?

 

ambient temperature increase leads to lost horsepower. However, before the car is warmed up, it will not be able to operate at its max potential. So I dont kno why your car is feeling faster before its warmed up...especially since vtec starts functioning when the temperature is warmed up...but temperatures do make a difference. If you run your car at the track on a hot day vs. a cold day, the car will run quicker on the cold day, given that the other conditions are the same.

 

yeah, i know what your saying... Well my VTEC engages smoothly/ when it comes on i dont' feel like a BANG! or anything and i'm taking off..(but it does get louder ) The engine always pulled strong very smoothly.

When its warmed up , it doesn feel 'slow' persay, just a little of the 'edge' is knocked off... and it's not as peppy i guess you could say... ahhaha

 

i think you're right about your intake and the hot air. for max power you want a hot engine getting cold air, but if you've got a short ram intake then once the engine is hot it's heating up all the air around it so you're sucking in hot air.

 

Aluminum intakes can sound pretty nice, but they are horrible heat magnets. This problem is amplified if you don't have a heat shield on your header (ie aftermarket, except for Comptech or whatever header comes with one). I did some testing a few months ago when it was hot outside... When I would stop at a light for not even a minute, the engine bay temp would shoot up somewhere above 160F and the temp of the intake tube would not be far behind. When the engine bay would cool down, the intake tube would retain the heat for a while. So, if you're in slow or stop-and-go conditions, the intake tube will just stay hot the whole time. Going at highway speeds will cool it, but it still takes time.

What I did was run some PVC between the front bumper's air dam and under the intake filter. When the car is moving, the intake is bombarded with outside "cold" air which also cools down the rest of the engine bay. It still gets very hot when stopped or going slow on a hot day, but it cools down faster and has a larger supply of air at highway speeds. It's not a huge improvement, but it's small cost for a small improvement. I can't honestly estimate how much it actually helps, and the gains won't show up on a dyno (since it's not also a windtunnel), but at least there seems to be a better throttle response and the intake tube doesn't get as hot.

 

sounds almost like a make shift scoop lol do u have a pic of that setup?

 

Yeah... I haven't gotten around to uploading pics of the one that I'm currently using, but here's the prototype:

http://www.vmac.org/~weston/dcp_2292.jpg
http://www.vmac.org/~weston/dcp_2294.jpg
http://www.vmac.org/~weston/dcp_2296.jpg
http://www.vmac.org/~weston/dcp_2297.jpg

It's just four 3" diameter PVC elbows. The one I'm using now has a black ABS piece in the air dam rather than PVC painted black, as well as screws to hold it all together and a drain hole so water wont stay inside. I also mounted the piece in the air dam a bit higher so it can get more air. I chose to use the same type of elbow for all four pieces, which is the type with only one coupling (the prototype had 3 of those and 1 with two couplings). It fits in there really nicely; I just had to rotate the horn a little towards the driver's side of the car (and pull it's wire through so I could do that).