2nd gen ram mileage/mpg improvements

[Mopar_Fanatic]

Hey everyone, its been a few weeks. I have some updates

1st, the fuel pump took a crap on me so it's got a new one now, doubt that'll do anything for mileage but we shall see. on my last tank, I averaged 12 mpg, which is better, but still not where i want to be. on this current tank, it's at 10 mpg (just ball-parking with the fuel gauge and the trip odometer, so not entirely accurate) which is partially due to hell once again freezing over again in Iowa, and also due to the header bolts backing out again (I swear, these damn things are going to be the bane of my existence.

2nd, I got some crap done to the truck to help with some fuel economy. the rear is now lowered 4 inches (the front was already dropped 2 inches, just hadn't gotten around to pulling the bed off to do the rear) and the spare tire has also been removed, but has been replaced with a couple of sandbags and my brother's wheels in the bed. it's supposed to warm up again next week and stay warm, so hopefully the sandbags will come out and then i can replace my bed liner with a bed mat.

now, time for everyone's favorite part of the gameshow. the questions

1st (this one is mainly for AJ, but anyone is welcome to chime in), is there a formula or something to calculate mpg improvement from reducing weight? it seems like something like that could be helpful.

2nd, does anyone know how I can get these damn headers to stop leaking? currently, I have grade 8 bolts with the spring style lock washers and tightened the piss out of all of them

thanks,

 

[AJ.]

2nd, does anyone know how I can get these damn headers to stop leaking? currently, I have grade 8 bolts with the spring style lock washers and tightened the piss out of all of them

Yeah, the secret is in the gaskets, and having thick flanges.
The hot/cold cycles just do that.
My TTI headers have about the thickest flanges I've ever seen, and the last set of gaskets that I bought, are the the thickest I've ever run. Together they are the best sealing chit that I've ever run. They have been on there since 2004 with no leaks, no loosening, no tightening required; and no, I do not recall the brand of the gasket, sorry; but I do remember that they were not cheap.
Oh, and I did NOT tighten the piss out of them, lol. But, worse, I think, is that my 367 has Edelbrock heads....IDK, maybe that's the secret, lol.

 

[AJ.]

1st (this one is mainly for AJ, but anyone is welcome to chime in), is there a formula or something to calculate mpg improvement from reducing weight? it seems like something like that could be helpful.

IDK if there is or not, I kindof doubt it.
I don't think there can be.
But there is a formula for computing fuel consumption to Power. As in, if your particular chassis requires "X" amount of power to go, "Y" mph, then the amount of fuel for that situation, can be calculated.

Somewhere I once read, that it takes 1/2 pound of fuel per horsepower, per hour.
So then,
If your chassis requires 60 hp to go 60 mph, that would be;
(60 x .5) 6pounds per gallon(ppg) = 5 gallons, and
5 gallons for 60 miles =12 miles per gallon.

If you then shave a bunch of weight off, and your chassis then requires only 55hp to go 60 mph, then;
(55 x .5)/6ppg =4.58 gallons, and that would be 13mpg.

But I do not know of any formula, that can directly predict mpg improvement from changes in weight. There may be one, I just don't know of it.

Some modern EFI computers can compute mpg from rate of fuel injected over distance traveled, but there is gonna be some tricky math involved.

Finally, Fuel consumption is rarely measured in steady-state. When you go by "the fuel used per trip", the trip usually includes periods when the vehicle is not moving, or is accelerating up to speed, and so on. Thus on short trips, those activities, plus warm-ups, can easily cut your economy in half.

For example, my 4-banger DD, in summer on long hauls, can hit in the range of 32mpg/US. But in winter, running back and forth to town, is lucky to get 60% of that, and with warm-ups, even less. But, I imagine, that you would know that.

Plus, trucks are usually calibrated rich in "open Loop" until the O2s kick in;
and, the O2s are kicked off under load sooner than in cars, which may have wide-band sensors..
and, any time the CEL is on, the ECU is/or may be, in "open loop" .
So then, in every case, it's very important that the CEL is NOT on, and that it's function has not been compromised..... like with an aftermarket programmer.

 

[Mopar_Fanatic]

Yeah, the secret is in the gaskets, and having thick flanges.
The hot/cold cycles just do that.
My TTI headers have about the thickest flanges I've ever seen, and the last set of gaskets that I bought, are the the thickest I've ever run. Together they are the best sealing chit that I've ever run. They have been on there since 2004 with no leaks, no loosening, no tightening required; and no, I do not recall the brand of the gasket, sorry; but I do remember that they were not cheap.
Oh, and I did NOT tighten the piss out of them, lol. But, worse, I think, is that my 367 has Edelbrock heads....IDK, maybe that's the secret, lol.

How thick were the flanges on your TTI's? My headers had some damn thick flanges, but they're made from chineseium (they were all of 165 bucks new if that tells you anything). I think I'm going to wait on buying gaskets as I have a 360 that's going in and I'm going to get a set of pacesetter long tubes to replace the china headers.

 

[AJ.]

How thick were the flanges on your TTI's?

I'm guessing, at least 3/8ths inch.
IIRC, I paid $495 for them, in 1999, plus shipping into Canada; and the dual 3" exhaust was about the same. This system is still on the car with only some minor rust-thru in the valleys of the merges.
Car was a DD until 2005/6. Every fall I would swap a 318 in, and every spring the 367 would go back in. and every year a different trans for at least one of them, and the 318 always got winter gears. Only the 318 ever got an automatic..... but not every winter, lol.