I was thinking it was about time to improve the performance of my 4.9 Liter, automatic. I realize that although they are known for reliability, it will never be an eight cylinder. But I would appreciate some thoughts on what to do and what items are really worth it. Do cat-back exhaust systems deliver a perceived difference? And what about the K&N FIPK system? Supprisingly expensive. Has that delivered any difference in performance? Did these modifications require any other mods (air/fuel adjustments, etc.)?

 

well I just put in the K&N FIPK and it's great....much much much better off the line(atleast with my 5spd) and a much faster throttle response when you floor it...I've heard Mcgyver's air box mod produces a close/same performance change.It's the best mod I've done for this 4.9L so far...but there isn't much out there for our engine..3 biggest would be FIPK,Exhaust,and computer chip.


Justin

 

How much did the K&N cost you?

 

It was $130 at 4 wheel parts .....http://www.4wheelparts.com it cost a few bucks more if you order from them online.

 

I was interested in doing the same on my 4.9. I looked on the website and they list 2 kits - one without Mass Air (WAY more expensive) and the one (with) for about $150. What's the difference?

 

The difference is in the application. The one with Mass Air is for trucks that have a Mass Air fuel injection system. The one with Speed Density (w/o Mass Air) is for trucks that have a Speed Density fuel injection system. The easiest way to tell if your vehicle has M/A or S/D is to check the air tubes going from your air filter box to your throttle body. If there is only one hose that braches into two, then you have a M/A system. If you have 2 hoses from the air box, then you have a S/D system. I wasn't aware of any 4.9L engines that had the M/A system, though. I thought it was just the 5.0L trucks in the mid-'90's

 

Well the 4.9L's were Speed Density until in 95.Some were M/A and some were S/D. All of the 96 4.9L were M/A. My truck is a 96.

BTW I heard this from PKRWUD

<---Hey I'm a senior member now