Join Date: Jul 2001
Location: Perth, WA, Aussi
Hi Guys, I already had a 2.5in exhaust and extractors and I had a crow cam fitted to my EF. At the same time I had some port work done (mild) ,had the extractors and intake ported to match the gaskets, had larger exhaust valves put in and better valve springs. Other minor things were done also (new sparks indexed to exhaust valves and 9mm Leads)
I would have to say that the cam does increase power, however on my car it has left me with a huge power robbing rich bog in the middle of the rev range (2000-3500) which seriously kills off acceleration. The computer doesn't understand the new pressures in the manifold at these revs and in my case the computer has just opened the injectors to 100% duty from 2500 onwards, this has left me with an A/F ratio falling from about 12.5:1 to 10:1 at 2500 until 3500 where the injectors run out of flow and the power curve rises very sharply by about 35rwhp, I'm getting a computer to sort this out (Probably a haltech).
Just a word of warning about taking it too far with the standard computer, they run rich from the factory and mods such as exhaust and cam make them run slightly richer, then as the revs rise and the fuel flow runs out you get a leaner A/F ratio (still very rich tho) and thus extra power (Thats the car pulling hard at about 3500 onwards, its not the cam - the cam is in range from about 1800-5500). If you have a unichip you can gain a significant power gain from leaning out the A/F Ratio to about 13.2:1
I would personally go for fully programable sequential injection eg Haltech Motec Autronic and run it in tandem with your ford computer. Let the ford computer control the A/C C/C Auto-Trans etc and the Aftermarket Comp control Idle fuel and spark, besides if you plan on going radically further (Over-bore 10:1 comp or super/turbocharging) the fully programable management will come in very handy, and will get you a MUCH better state of tune, better fuel econ and power
Hrmmm gotten a little off track haven't I....Sorry : /
Oh and cost was about $2k with full rebuild of the head and aformentioned mods except the exhaust which cost another $600