ok i have a 04 f150 and so far the only engine mod i have is a k&n cai.
when i floor it there seems to be a lag kinda before it starts to take off.. and when i get to about to 45-50 mph it seems to kinda slow down the acceleration even though i have it floored..

i was wondering if that is common and or if there is a nother mod i could get to change that

thanks

 

Make sure everything is hooked up tight and correctly. I'm thinking 1 of 2 things. Try and resetting the computer when the engine is cold. Disconnect the battery for about 15mins. Hook it back up and see what happens.

Second, I highly doubt this but it's just a thought. Maybe the CAI is putting too much backpressure on the engine causing it to lose acceleration on the top end. CAI's only work best if you have an aftermarket exhaust on the truck. Make sure nothing else is wrong with the truck too.

 

Mine did the same thing when I threw my CAI on and it evened out after the exhaust was put on. The tunes really lit a fire under it's a** though.

 

honestly my truck is freakin slow too, i only have a 4.6L but you would think that it being a single cab it would still be quick on its feet.
-i have a sct tuner+ flowmaster exhaust+ k&n filter

 

you runnin the k&N cai or just the filter??

 

ive got the actual cai..
im looking into the edge evolution programmer as well as a borla exhaust system... some things that i have herd about the two..

1. on a programmer.... i read where after hooking it up it blew the guys engine to hell.. that scares me...

2. on a exhaust.... i read and have herd that all a exhaust does is make the truck sound better and it has no actual performance value.

but thats just what i have herd... i might be totally wrong..

 

You heard wrong. Totally wrong. In order for an engine to gulp more cool air, you installed a cold air box. This is good. However, an engine is nothing more than a large air pump. In order for the air to come in, it has to get out. You really need a better exhaust to take advantage of the air cleaner setup you installed.

The other poster has me confused with his 4.6. He installed an exhaust, a K&N air cleaner (did not specify if it was just a filter or the cold air box). Nor did he specify the size of his exhaust. Using too large of an exhaust pipe will hurt the small block performance; a little back pressure is good. You want clean, mandral bent tubes to allow the exhaust to flow. I suspect his tuner is too aggressive, but I cannot render an opinion without knowing his details.

 

I agree Bucko. Alot of people just throw mods on their trucks without knowing the fundementals of them. More air in must equl more air out. I own a 4.6 Screw that will run with the big dogs. And the only mods i have is larger intake and 2.5" true dual exhaust.Ford has fine tuned most of the engines, so if you are going to mod them you must RESEARCH first. I can make a 4 banger sound good but will it run is the question.

 

Buck is right..you need to allow all that new airflow a way out. Research some exhaust systems. Borla is very nice so is Gibson. Those are a little higher end $$ wise.

As for your prorgrammer, after you get your exhuast done look into custom tunes for a tuner like the SCT line or a Gryphon (edge).

www.troyerperformance.com
www.vmptuning.com
www.powerhungryperformance.com

Those are some tuners..there are more, but those are three of the biggest and well known.


If you have all three and they work together you can have a totally different beast at your disposal.

 

either yall get paid for referals for these tuners or they are just REALLY good....... Ive yet to figure it out. who has the bad aspects of these?