crotchety old man

Hi,
I am brand new to the forum and have a question about rebuildig a 5.3 for mileage. First I MUST comment on the Ford add. If I knew then what I know now about Ford diesels, if they offered to GIVE me the truck with the understanding that I had to drive it maintain it and DEPEND on it I would not have taken it. I have spent more money keeping this thing running for a year and a half than I spent for the chevy it replaced! Mine is presently down AGAIN and I am waiting for it to be towed home so I can get it running long enough to trade it in on a Chev/GMC. I consider ford to be a four letter word.

The question. I am looking at '05 because it apparently is the last year for quadrasteer. My question is has anyone done a complete overhaul, in frame or out, with the intention of increasing fuel economy? Back in the dark ages we did this a few times on carburated engines with much success. I would guess that the computerized engines pose a whole host of variables that can screw up the best intentions. I need bottom end and mid range and am not worried about anything above 4000 to 4500. The questions would include head work, my experience back when was that cleaning up the ports prevented a lot of fuel droplets from forming. Cam timing ie: does anyone grind something specifically for economy? Exhaust, I have found in the past that headers are actually a deterent to economy particularly on the old 454 dually's. Compression, bump it up or will a compression bump require higher octane fuel thereby negating any mileage improvement. Reprogramming computer, does it work for what I am attempting to accomplish? And obviously any other things I have overlooked. Also when I get there is there a thread that has assembly tips as this will be my first foray into the newer generation engine. I built my first small block back in the early 60's and pretty much have all the questions answered on those but this will be a new experience.

Fishinfooleric10@aol.com

Hey man welcome to the forum and if you are going for just fuel economy and no performance, I would not worrying about rebuilding the motor. All I would do is buy a chip and put it in fuel economy mode. They are definitely worth the money and will increase your fuel economy a good bit. I tell you this because unless you just want to rebuild the motor, then save time and alot of money and just buy a programmer.

crotchety old man

I am only interested in mileage, I have spent enough of my time under a hood and am not looking for a project but would be willing to if the end result would be worth it. For the most part this truck will be used as a passenger car with a really big trunk. If my '99 suburban with the first gen vortec that as I remember developed around 190 HP did everything I needed I am certain that the 5.3 will do fine.

So having said that, if the programmers really work which is the best. If you have knowledge of them what kind of gains are realistically obtainable? Obviously it would be considerably easier, not to mention less time consuming, to plug in a programmer than to open up the engine.

I come from the dark ages when to make an engine do something other than it did stock you needed to bolt on new parts, sometimes a LOT of new parts. We once built a 65 Nova with a 307 that averaged 19 in town and 29 on the road. We thought a lot about the combination of engine parts and obviously got lucky and found just the right combination.

country_09

Just a custom tune via blackbear performance or gowheatley.com. Other than that proper maintenance. As you know when you start addin hp numbers, mpg go down.

Fishinfooleric10@aol.com

SCT powerchips are a good way to go I believe

crotchety old man

Not necessarily, mileage and HP are not mutually exclusive. It depends on WHERE you are adding the HP. Generally HP improvements are in the upper RPM ranges which means you are killing the bottom end which is the street driving range ergo bad economy. If on the other hand you are increasing cylinder pressures at the same throttle opening (economy and HP relate directly to cylinder pressure vs. throttle opening) in the lower RPM range you are actually adding HP on the bottom and taking it from the top. Result, increased economy.
Generally this is done primarily with cam timing, port and valve size, carburetor and intake manifold design, static compression ratio, ignition timing etc.
Do I know that this formula works, yes. On a non computerized engine where I have complete control over all variables; mixture, comp ratio, cam timing, ign advance etc. I can dial an engine to run best in whatever rpm range I want. As I have never attempted to dial in a computerized engine, the great unknown to me is how the computerized system will react to those modifications and if it will react negatively to the point that it will negate the expected improvements.
This all brings me back to the original question because theoretically if I can find the right combinaton that will work harmoniously with the vehicles computer it should result in greatly improved bottom end and mid range at the expense of top end.

country_09

Wasn't tryin to get into specifics, I'm mean in general more hp means you're goin to want to hit the throttle more than normal, ergo your gas mileage gets worse.

IMO it wouldn't make sense to completely rebuild and get 1-2 mpg more and havin to mess with the electrical components when you could just send the PCM off and get it tuned for gas mileage and get 2-3 mpg drivin conservatively.

crotchety old man

Couldn't agree more. I have just seen threads here and there that state the reprogramming usually does not work and in some cases makes it worse.

If you have knowledge that reprogramming does in fact work It is definately the way to go.

country_09

Which is why I don't recommend using a "programmer" so to speak. They work well on older trucks, pre 99, but then trucks started gettin more electrically controlled. Leads me to another reason why I always recommended blackbear performance or Wheatley tuning to do them because they have a large base of people they've tuned and know exactly what they're doing

crotchety old man

I had never heard of either of them so did a google search. Could not even find a web site for Wheatley but Blackbear is just down the road from me in San Diego. I get down there with some frequency so might just drop in for a chat. I understand why their reprogram works while others don't. They are gathering information on your driving habits and then tuning specifically for you and your vehicle. Like it.

Thanks for the information.

I found the truck I want, now if I could just get this_)&^*&^$*)(&^%$ ford running long enough to trade it in. I bolted $600.00 worth of rebuilt electronics on it this week just to get it running well enough to move it to a spot where we can put it on a flatbed and drag it down here. Bring your chevy and your fishing gear, bring your ford and your autoclub card