New toy have a question?

[over2tonsofFun]

So the heads are similar to the HO heads?

Tim

[knucklehead0202]

E5 heads were on pretty much everything that year, including the HO. They're better than some, but overall would still be considered garbage compared to anything modern. I know some nerds have gone to great lengths with porting and such on the E5/6/7 heads to see what they'll do, but unless you're a professional porter with lots of spare time, buy some gt40's or better yet, aftermarket heads like edelbrock, afr, tfs, etc. They are all MILES ahead of the factory ford stuff and will save you trouble in the long run. Find them used for reasonable prices on mustang forums. I picked up some RHS 200's for like 800 bucks and they cost more than twice that new. Weren't going to work for what I wanted to do at the time so I traded them straight across for some Edelbrock's fresh out of the machine shop. There are deals to be had on good stuff.

[gadget73]

I think the 85 was rated at 155 hp, the 84 was rated at 140, so it did improve. 86 was rated 150 with single exhaust, 160 with dual. I won't pretend the better heads (vs the 84 and arguably the 86) made it a barn stormer but if you drive a proper running 84 and a proper running 85, you'll feel the difference. They all still suck, you're just distinguishing between levels of suck.

[HiFiMerc]

The '84 I had was a complete dog, but it ran so smooth at 55 in overdrive. I learned long after it was gone (threw a rod at 198k) that it had the timing chain replaced several years before i got it. (I was the 4th generation to drive it.)

Also, after you turn the key on, you have to push the pedal to the floor and release. To set the choke I think on a CFI car?? Been over 10 years.

[gadget73]

kind-of a choke. Mechanical high idle system identical to what carbs had, just no choke flap on top. Same choke heater and all that crap though.

[DerekTheGreat]

In '85 for the Ford literature I read through rated them at 150hp with single exhaust. You only have to have that choke pull-off mechanism working properly if you want the car to idle when cold. So stupid that they couldn't figure out how to use the computer to enrichen the idle mixture based on coolant temperature. If you don't have your idle ~1700rpm (Ford wanted ~2,200 from factory!) the car will surge due to it not doing the enrichment thing, manifold vacuum drops, this is picked up by MAP sensor, it throws gas at it, RPM goes up, rinse and repeat until stall or car warms up.

[gadget73]

It does fatten the mix up, but there is not really any idle speed control. Keep in mind its basically a carb, so you have icing problems to worry about too, which is what the flapper in the exhaust was about. it forced the exhaust through the crossover in the intake to put some heat under the throttle body. The idle speed bump for the AC wouldn't run it up enough to get things working I guess. When all that works right, it doesn't stall or do stupid things. Unfortunately many of them don't work right or have other braindead issues that make it troublesome.

Its a pretty crude fuel injection method when you get right down to it, but its a fairly obvious step from the purely mechanical carb to a multiport injection design. The actual ECM logic is very similar, and other than driving more injectors that ECM is pretty much what works the truck batch fire system. It has only 2 injector drivers, each driving 2 injectors per head. The CFI works that way too if you look at the manifold design, each injector feeds fuel to a pair of inner cylinders on one side and a pair of outer cylinders on the opposite side. GM's throttle body system seemed to work better, but Ford got it pretty right when they went sequential multiport.


Its also easy to criticize the design shortcomings now, 30 odd years after it was created. Consider the computer tech at the time and realize that the entirety of an 80s EEC-IV program is 32k in size, and ran on I believe a 4 mhz processor, they did pretty good with what was available. The fact that it still works all these years later, and can be tweaked and diddled pretty extensively speaks of a pretty sound design.

[knucklehead0202]

I think the 85 was rated at 155 hp, the 84 was rated at 140, so it did improve. 86 was rated 150 with single exhaust, 160 with dual. I won't pretend the better heads (vs the 84 and arguably the 86) made it a barn stormer but if you drive a proper running 84 and a proper running 85, you'll feel the difference. They all still suck, you're just distinguishing between levels of suck.

Hahahahaha different levels of suck. That pretty well sums it up. It's kind of like the stages of modding a lopo. You stick exhaust on it, think it's a little better. Do some induction work, little better. Go stupid like me and stick a whole top end on it, completely lose your low end and have the wrong rear gears/converter for the new stuff, etc. Real pisser was that the computer was just starting to figure out how to make that thing run good when it got wrecked. Oh well, life goes on...