I just recently sold my 76 4x4 F-250 single cab for my new project. I was just needing a little schooling on what exactly I bought. I had the truck checked out by a local diesel shop and they said it was pretty solid.

It has gauges, superchip micromax tuner, stock air filter, ATS intercooler, and I think it has a downpipe and cat delete(the pipe out of the turbo is round and stainless not flattened at all and it goes out next to the firewall and then there is only the muffler and 4inch pipe),

I know I need the 6637 and I think I have a MAP sensor mod but if I don't I need one. Which one?
the return hose from the intercooler has a bung with a wire that plugs into the passenger side of the engine next to another electrical connection.

I guess I'll stop now. I really want to get the mileage up on this thing so I don't have to buy a car to go to work.
Is 24mpg with direct propane injection among other things a pipe dream? I heard that claim and I want to believe.

If I do the 6637 will it lower my EGT's and increase boost?
I seem a bit hot and lagging

thanks,
Jeff

 

i dont think 24mpg is a pipe dream the one in my sig gets around 20 most times as for the rest someone else is better suited to answer this and welcome roll the coal!!

 

When I am in park and rev the engine I get virtually no boost. I went up to 2700rpm and held it there for a bit. does it only boost when under load?

 

Correct, no boost unless under load.

 

the 6637 will cool EGT's and raise boost.
24 MPG would be at the edge of my imagination, but not out of it...
Be careful with propane, because of your compression ratio, it may predetonate if you use too much and that could be dangerous/damaging.
That line you're seeing on the return tube is the Manifold Absolute pressure (MAP) sensor. Moving it over to the compressor side will reduce lag greatly.

 

I have heard of some people squeezing slightly over 20 mpg. But the before mentioned is almost ALWAYS with a 250 model, wich has less weight, and the more fuel efficent rear end. Even if your truck is a single rear, you wont get it. I have owned 4 powerstrokes now and the best I have ever seen was 18.5, in my 99 250. Realistically, your going to see somewhere between 13 and 17. Supertuner would be the first thing that I got rid of. Get a DP tuner or a tw CHIP.
The 6637 filter will do neither, increase your boost or reduce EGTs (unless your filter now has the walmart mod, I.E. paper bag over it or completely clogged.)

 

best ive ever gotten out of mine was 24.2 mpg. averages right around 22 mpg. but thats only if i run it at 55 mph the entire trip. once i get up around 65-70 it drops down to about 19 mpg. mine is a reg cab xl 250, 5 speed, 4.10 with no power anything on it though. stock tires, no brush guards, tool boxes, etc. so it doesnt weigh hardly anything.

 

so I got one it will reduce egt's and increase boost and one in the won't category I think we'll need a tie breaker to chime in. We're talking about the 6637.

Also on the MAP sensor. it does come off the intercooler return pipe and then has a tee that a wire comes out of is that the boost sensor? and if so then I guess I don't have the map sensor mod. can I add one? which one?

 

i say it will increase boost and lower egt's but it will be such a small amount you will bearly see anything on your gauges.

 

The 6637 will save the blades on your turbo....tie breaker!

 

EXACTLY!!!

 

I am with the saving turbo fins, but boost and egt is a no go......... UNLESS your current setup is VERY clogged. The negative pressure or vacum that the turbo makes on the pipe side of the airfilter would NOT be effected unless more than 60 percent of the airfilter was completely blocked off. Think about it. It draws enough air thru the intake inlet feed pipe to supply the turbo, and witht eh airfilter having almost 10 times as much surface area, you would technically need only a small percentage of an area BIGGER than the pipe itself to make adequate supply. Its simple physics really. So if you still have that amount of area, your boost will not increase, so your egts will not be lowered. The airfilter would have to be a restriction first before it could be a boost gain or egt loss.

 

what could I do to increase boost? short of bigger turbo

Should I get some bb's and stop off at radio shack first?

 

I don't know how you guys come up with this stuff but I'm glad you do

 

only way to actually increase boost is more fuel. You can get a better tuner, you will see a few pounds, or bigger sticks and let the coal roll..............