so i take it that modding our pcm's isn't as simple as replacing a chip and then re programing them with different fuel maps and what not

 

You have to know what to mod if you're going to change the standard fuel or spark maps. This is why most people buy a chip that someone else has already done the re-calibration work on, because most of us do not have the ability to do the necessary measurements. The problem is, again, you may not always be able to find a calibration that works exactly for your configuration. Since no one is selling a pre-programmed chip for the EEC-IV running the engines in Aerostars, you would have to get something close to it, like for Rangers or Explorers, and hope that it works. Otherwise, you would have to home grow your own, and without the proper measurement tools, it's really hard to do.

Anyway, back to the original question of whether a cam change will be worth the cost, the answer is "maybe". I spoke to a tech at Comp Cams today about their offerings for the 4 liter v6. He said that the stock EEC-IV should be able to easily accommodate the smaller cam, which, as advertised, is designed to provide better low end torque mainly from increased exhaust valve lift, and slightly improve fuel economy. The improvements would be a few to 10%; enough to be noticed.

The bigger cam is intended for more power at higher rpms, and will indeed work better with bigger valves and ported intakes. It will push the limits of what the stock EEC will be able to handle, and you will probably need an adjustable fuel pressure regulator to increase fuel pressure to keep up with the additional air flow. They highly recommend reprogramming the EEC with this cam. If you operate in those speed ranges, the engine will consume more fuel, so it's not an economy cam. The stock configuration flows so poorly that overall performance improvement from the modifications will compensate for what torque might normally be lost at the low end from a bigger cam, so that would be a wash; you will not notice any loss down below. Overall improvements would be harder to predict, since so many different things can or have to be done.

Both cams open the valves about as high as they can without having to cut new reliefs in the pistons; the smaller cam only hits the limit on the exhaust, while the bigger cam does it on both. Like a lot of stock Ford engines, the 4 liter v6 head has very poor exhaust flow. Then a more free-flowing exhaust system will help a lot. (At least replace the stock T-shaped cat pipe with a true Y-pipe.)

 

Gentlemen,

I have changed a number of cams in my life. I was usually talked into an RV cam or whatever. Results were disappointing.

One switch I made that was totally wonderful was installing a low rpm economy cam. Low duration, tiny lift and little overlap. I know the engine made less horsepower but the low end torque was WONDERFUL. It felt like a diesel and mileage was improved.

This was on a heavy duty, heavily loaded work vehicle.

Ken

 

i totally agree Ken,

too bad the auto industry has taken away those great low rpm high torque from the hole engines from years past and given us these things we have to wind out to 3000 rpm before we get in the torque curve. they are not fun to drive on hills and head wind nor take off or merge on a freeway with heavy load. my 4L Aero is an amazing low rpm torquey engine that has low end pull, impressed me trailer pulling but became too high mileage to trust totally on long trips.

once over cammed a BB Chevy 454 in a pickup in the early 70s with a medium high lift wide duration Iskenderian cam, had to wind it up to 3000 rpm to have any pulling torque but what a screamer pulling. sucked gas but would pull all day towing 6000 lbs at 80 mph
the stock cam was anemic.

 

Interesting, Mine was also a 454 chevy. The small cam made driving it very pleasurable, BIG difference. I also switched to a low stall rv torque converter.

I know it would have lost in a race because the hp was lower but this is how I would recam anything I owned if I had to. There was a significant mileage increase.

The guys at the auto parts store do not really know anything and just sell based on the propaganda.

Ken

 

If the outfit that makes the cam claims that you can do it with an otherwise stock setup, I would go for it.

On a freer flowing exhaust, I am working on a new solution for replacing the stock cat with one that has a better y-pipe. I have a couple projects going on, including having a shop fabricate some headers for my ride. Mine will have a completely custom exhaust system when I am done, but I also want to make stuff that bolts onto the stock manifolds that anyone can put on themselves.

 

I did some checking at Summit and Jegs. The milder cam goes for about $270.

I stink at math even though I made it through Calculas in college but if I figure on gaining 1mpg (18 vs 17 in city) it would take 32K miles to recoup the cost of the cam.
That would take me about 10 years with the kind of miles I put on the Aero anymore.
Moral of the story: unless the old cam is bad, it's not worth it to me at that price.
Same goes for the exhaust. Until mine wears out, there's no payback.
I think I'll put my money where it does the most good. Besides fixing the leaks, I need to improve the suspension so it handles better. I sure wish I could find some second row chairs.

 

To each their own, for me, I like more power too. That cam would deliver more power at low RPM, which would have its bonuses. In the long run, what are you gonna replace the Aero with? Maybe another, but those are getting rarer. Most that I have seen have body damage. Mine on the other hand is nearly pristine, so for me, investing in the one I have makes sense. The catback exhaust by itself has little effect on gas mileage, at least not in my case, but it would support other mods quite well, and the performance difference is quite noticeable. The stupid -y-pipe is a poor design, and is probably the next bottleneck and one of the reasons my economy hadn't changed much. It does not merge the gases properly, and it chokes everything down right at that point.

My cats work just fine too, but the heat shields are failing, making rattle noises. I have had them repaired three times, but they cannot be fixed anymore. I cannot simply remove them because the idea is that they help protect the trans from heat. That noise annoys me, so that justifies me in replacing the cats, especially if it helps me make a better replacement for all of you guys.

The original system was rather cheaply designed. Some of the stuff if pretty good in terms of materials and construction techniques, it was the actual implementation that sucked. You can't take a muffler for a 4 cylinder and use it on all the V6 models and get optimum power and economy. Ford made this decision strictly so that they could save money by making one sized muffler fit everything.

 

The reason why I frown on messing with the aero engines is I have messed with many engines over the years..Sure the exhaust is restictive sure the engine could breath better..Things are designed that way for a reason. Most of us don't drag race our vans so opening up the exhaust just hurts bottom end and possibly midrange performance. All these restrictions really work to keep the van with good low end torque and throttle response..As far as mileage it may get worse not better. My 96's all run great with more power than I ever need.
My advice is don't mess with what works..you may find yourself wasting $$$$$. All mine can get 20-21 on highway loaded and they are all AWD ext.

Dick

 

I hear exactly what you are saying. My motto in the past has always been "why just fix it when you can make it better" but I don't seem to have the money to throw into cars like I used to. I put way more into my Escort wagon than I probably should have but it is my daily driver now and I get almost 30MPG in town.

I really only use the Aero to tow or haul bulky stuff. It's in great shape and I mean to keep it as long as I can support it. If the cam were half that price I'd probably jump on it. I need to do some soul searching

 

However, opening up restrictions does not hurt gas mileage. It has nothing to do with backpressure, it has to do with induction. My van only gets 17 mpg, but on the flip side, it has always gotten that, and my brothers gets the same. In Utah there are a lot of hills, and this makes it difficult to get great gas mileage. However, mine gets about the same mileage all the time, regardless of how much weight I haul around.

My mileage is better than when I first bought it. The biggest difference I found with opening up the exhaust was the gain in performance. I did not loose any economy, in fact it did get slightly better. But the performance moves up several notches. It has more get up and go right off the line, and sustains that power throughout. For me the power is important, because the more power I have, the more I can effectively haul. I frequently haul loads over 1000 lbs, and have to do so up and down hills. The extra power has another effect. I don't have to have my foot on the throttle as much, so the shifts are sooner and I can sustain torque converter lockup longer, meaning I can pull up hills with loads without having to drop out of OD very often. As soon as the torque converter does unlock, I drop it down to third.

Switching to a 2.25" catback is not an excessive size. The 4.0L is actually built for it, Ford uses 2.25" pipe for the converter itself. They neck it down to 2" so they can use the smaller 2" flex pipe and muffler. It is the same muffler used on the 2.3L Ranger. That muffler necks down to 1.75" inside, and makes 2 complete 180 turns. This is the cheapest way to make a quiet muffler. So Ford compromised for the convenience and cheapness of using one muffler for everything rather than using the right size for the 4.0L. The 4.0L responds well to the increased catback size, I know, I have done it on more than one Aerostar. The 3.0L less so.

 

Still trying to justify the cam: I've noticed that since I don't drive the Aero very often, the lifters tend to leak down. I get some clatter for a few seconds until they pump back up. Is this normal? Maybe I need to buy the cam and new lifters?

I will probably do the catback someday but for now I just want to pull the parts together to fix the leaks, replace the water pump, inspect the timing chain and replace the front seal. Do the shorty and the extended use the same exhaust system?

 

Well, having no experience with new cams, I agree to some point. And they will be sacrificing power in one part of the powerband for performance in another. So if you drive very mild to maximize economy it might eventually save money, but you do have to factor in how many years that would take. And with me, having more low end torque would have benefits, but because I do haul heavy loads at speed, total horsepower is important too. So for me the cam wouldn't be justified either.

For the clatter, what oil are you running. For a temporary fix and to make sure that gum and varnis aren't the culprits, you can add some rislone to the oil. Its a detergent that can help clean the engine. I don't believe in snake oil, but I used it one time when my valvetrain started making noise, it cleared it up in a hurry, and fixed the problem, as in it never made noise again and I never had to add rislone again. Make sure you use a top quality filter with an anti-drainback valve.

On the lifters, if you are tearing down to do an intake and valve covers anyway, the pushrods and lifters are right there. I would inspect them at the very least, and consider replacing the lifters.

These engines do best with a 5w30 or so. Heavier oils tend to take longer to flow up to the valve and cam, and result in increased startup wear. The important number is the first part, the 5wXX. If you use a 10wXX oil, the oil is thicker at startup and will resist flow more. If the second number is the same it makes no difference as that is the viscosity index at operating temperature. If you stick with 5w30 instead of 10w30 or 10w40 you will be fine. Synthetic oils can make a difference too, but they will not fix an engine that might already have some wear issues. And they are not right for everyone.

On the exhaust system it does fit all Aerostars in the listed years. The shorty and extended use the same system. Prior to 1990, the systems were different from the later setup.

 

Hey Guys;

To start I am not trying to sell you anythig but if you don't already know about Water4Gas I suggest you You Tube it. There are loads of videos about Hydrogen on Demand.

It is a very simple system you can install your self. I have a 1992 Aerostar 4L XLT AWD full custom package. I installed 2 canisters on my van and picked up 4 (reliable) MPG hwy and 2 MPG city and I would guess 20-30 % HP. I will not try to explain the system to you but to say it is so simple I built and mounted the unit myself. A up front cost is LOW and the payback is quick.


The information is Public Domain. Like the man said Try it you,ll like it

ps/ super low maintainance I know you will be glad you looked



Any of you that read this thread uTube water4gas

Garry