so, i've posted about the auto to zf5 swap i'll be doing come spring time, and i have nearly all my ducks in a row for the project. one thing that i haven't sorted out yet, though is the reflash of my PCM. i know some guys say you have to reflash it. others have run a manual trans with an auto PCM with anything from no issues at all, to a crazy up-and-down idle that sounds hilarious.

i'm thinking i probably will reflash - especially when the guy i bought my zf5 from said he has just done a swap for a friend and sent his PCM to DP Tuner who updated the software for $50. without even asking my local dealership, i figure $50 is going to be cheaper than having them do it - plus, i'm sure they'd give me a whole line of BS as to why they can't, or why i need to buy a new PCM or something.

anyway, so i emailed DP Tuner and they responded that they can do it, but that i have the option of stock manual software, or a wide variety of tunes that they offer (for just $30 more). now, as i said to them, while i would certainly like more power and more awesomeness for my truck, my main goal with my truck is to drive it forever. so, as nothing in life is free, i figure more power comes at the expense of more engine wear and less life...

so my question for you all is: what would their 1-step above stock tune of "60+ horsepower with increased fuel economy" be doing to my truck in terms of how my engine functions?

i figure its gotta be dumping more fuel (or at least changing the timing of the fuel injectors) into the cylinders at certain RPMs to get more power, but then its gotta be dumping less fuel at other RPMs for better mileage.

if it was an automatic tune, i could see it changing shift points to accomplish better fuel economy, but with a manual trans, i'll be controlling the shifting - manually, obviously - so, how can they claim to effect mileage without simply delivering less fuel at cruising RPMs. but that runs counter to adding 60 hp by software changes alone...

ok, you can see where my questions lie.

anyone with any experience on this? or just different tunes in general?

i don't want to spend the money on a full-out multiposition chip, but for $30, if i can get a better-running rig, with no downside, then why not, right?

 

If it's all stock then just go with the stock tune and add a chip later on if/when you want more power and performance.

But for $30 more I kind of want to say go for it. There is a lot of room to grow with these older trucks and a tune will certainly wake it up, without really stressing anything out as far as longevity goes if you have stock injectors.

Just remember that with a 60 hp tune, you can never run stock hp, you will be at 60 all the time. With an add-on chip you can get a stock hp file on one of the positions.

 

I sent DP a pcm atleast 5 years ago had him reflash it to the latest and greatest tune and also put the 80hp tune on it. I would do it again in an instant if i didnt have 4 chips sitting around here.....it was worth every dollar,.as for the milage claims, there true too, it's alot to explain but better timing is the biggest reason for it.

Diesel Rod

 

good enough for me. i'm still curious to figure out why there can be so much improvement. i kind of figured it was mostly timing and pulse-width. and i'm guessing 60 HP is an optimistic estimate assuming everything else is in perfect working order...

and, Jim - we were just emailing about RevX the other day. i guess FTE is a pretty small world.

anyway - i figure i'll go for the 60 hp/econo tune. if for whatever reason i really don't like it, i can always go back to stock for $50, or bite the bullet and buy a multi-position chip with a stock tune position at that point in time.

 

All my chips have a stock setting and i dont think i have ever used it. I put it on there just in case, but discovered the egt's werent that bad and controllable with my foot amd down shifting. I ever get one reburned it most likely wont have a stock setting other then high idle.

 

Rod.what is your favorite,best economy tune?heck for now for what I do I would do a reflash and one tune.that will get me by until the fun begins.

 

In very simple generic terms, think like this:
The injectors are like a syringe. You push the plunger down and fluid comes out the nozzle (or needle staying with a syringe analogy).
Let's say the stock injector has a plunger 2" long, but the stock computer is only telling it to push 1" down. You only get so much fuel out pushing it 1" down when it's capable of more.
Now add a chip and change the tuning and tell it to actually push all the way, the full 2" and you get more performance out of the stock injectors.

Now send the injectors to me and I modify them to push 3", or 4" etc and along with the appropriate tuning you can get varying degrees of performance gains.

Does that help?

 

very much so. so i'll essentially be stressing my old, mostly worn-out injectors somewhat more, but they will need a rebuild someday anyway, so no big change there. heads and headgaskets get a little more force on them from the larger charge detonation, but since alot of you guys are running much more fuel than i will be, i feel OK there.

i'll be rebuilding my turbo soon, so should be OK there. i have a feeling i have a valve on its way out somewhere as well, but this shouldnt make that too much worse...

i want to do a pyro to monitor EGT's anyway (even though i rarely tow), so maybe this'll just push me to do that sooner.

thanks again guys.

 

Some more info for you.
Stock injectors with a chip will flow about 90 cc of fuel.
The '99 - '03 trucks move about 140 cc of fuel with a chip.

Adding a chip to your truck is really no where near as stressful as what a chipped '99 - '03 Super dutie go through every day.
As long as your parts are in good shape (turbo, trans, heads, head gaskets, etc), you will be fine.
A chip itself will not hurt the older injectors/truck at all.

 

thanks for the additional info. being an engineer, i like direct number comparisons like that - though the syringe analogy was very good also :-)

only problem is that i really have no idea what shape my heads, gaskets and injectors are in - i'll be rebuilding the turbo so i should be OK there; the trans will be a used manual, so we'll see about that; the injectors are probably on their way out, so maybe they'll need a rebuild soon... as for the heads and gaskets - if they're nearly shot already, though, an extra 60 HP is just going to bring the problem to the surface sooner rather than later - i'm OK with that gamble, though, so i think i'll go for the tune.

also, now that i think about it, i remember seeing a table somewhere that the 96 model year powerstrokes were the lowest factory horsepower rated of all the 7.3 PSD years. i don't remember what the highest rating was, but assuming they used the same heads, crank bearings, etc on all 7.3 PSD years, if the ford/navistar thought it was OK to bump the HP significantly, then 60 hp extra should be ok in my rig. its not like i floor it all the time anyway...

 

The 94.5, 95, & 96's were all 215HP, The 97's were 225HP. the ONLY difference was the pcm. They all used the exact same parts. The 03 psd's with a manual trans were rated 275HP, they used the same long block as your truck.

As for the head gaskets, some guys just pull the stock head bolts out, put studs in without ever even lifting the head or changing the gaskets and make 400HP........your heads and gaskets are fine.

Diesel Rod

 

great - i'm feeling much better about all this now. probably would have done it anyway - who doesnt want more HP if its cheap and shouldn't cause toooo much more wear? but knowing that the risks are pretty low lets me rationalize it alot better.

thanks guys.