bombing for MPG

[CUMIN2pass]

I have bad fuel milage and want to make mods for "best " fuel milage. I drive 75% city. I have 245/75/16 tires,3. 54 rear end,



I like the modified turbo with 12cm2/ TC 91% VB 4" pipe and

275"s . All advise welcome.

 

[Alan Reagan]

Add a VA box and don't take advantage of the increase in power and torque. That can get you up about 1. 5 to 2 mpg. It changes the timing and adds fuel as necessary.

 

[Ramafid]

A small fueling box would more than likely be your best bet along with a free flowing exhaust. I don't think the turbo will help and the injectors usually don't help unless you're on the hwy. What's your fuel mileage? What you think is bad may be just normal.

 

[Ted Constantine]

Try an EZ edge or better yet the DD version with the timing only setting. Do you have a 2wd or 4wd? What tires are you running?



The biggest thing for economy is the use of your right foot.



Ted



HAVE YOU CHECKED YOUR IAT SENSOR?



IS THE LIST OF MODS IN YOUR POST, THINGS YOU HAVE OR WOULD LIKE?

 

[CUMIN2pass]

I have 2 wd stock truck I have been reading people get the T/C

and VB first. Then I was thinking super turbo from PDR to get high boost at low rpm. What I listed was mods to come. I have 275's not yet installed. I have low transfer pump pressure , working to get Dodge to replace it. I did take the IAT out and clean it.

 

[WAYNE]

Ok guys dont laugh, i've been testing a product called the vortex valve. They claim a definite improvement in mileage or your money back. I tow a race car with my truck, I can tell you for a fact that towing the car on the highway at 70mph (my usual speed) I saw a 2mpg. increase (figuring by actual gallons used)

I saw the link for their website right on the TDR. I havent figured my around town mileage yet, but can tell it's already better. Basically this stainless steel valve simply installs in the intake and swirls the incoming air into the motor which makes for a better, complete burn, therefore better mileage.

 

[Ted Constantine]

CUMIN2pass,

Ok with that clarification where to start? You have the 275s. I am running 275s w/ the EZ. Without the EZ it feels like I can only use half the engine. It defuels between 1/3 and 1/2 throttle. With the EZ it is a relative rocket and I run it on the lowest setting. The boost part of the box is necessary. (to be realistic non of this stuff is "necessary") I also have a JRE 4" exhaust. Unfortunetly I did all my mods at almost the same time and while the truck was still breaking in, so I have no real MPG data. I definitely gain MPG with the EZ as I have run my truck with and without recently.



I think the only thing that hurts my MPG are my tires and LACK of self restraint.



As for the turbo. I am probably going to have one of Pier's turbos in the next month. I did not even start to think about changing turbos until I have moved up in altitude. Try the 275s and EZ first it might be all you want



There is a very good article in issue 33 on How to drive in Technical Topics by Robert Patton. This article makes you think about your driving style and talk at one point about driving with your boost gauge for better economy. This is not related directly to your quest but I does make you think about the fact that if you are producing more boost you are burning a lot of fuel to do so with any turbo. Performance mods only help economy if you can control your right foot. This is a concept that costs me a lot of money at the pump. I really like my right foot.



I should clarify that I like the idea of piers turbo but think that you should do this in steps and observe the changes you get from each mod.



With the transmission talk to Bill Kondolly or MassDiesel. They can steer you straight. you will want the transmission mods with these other performance mods.



If you really are focusing on MPG only check out the DD true torque power module. It is an EZ with a slightly different program. The lowest setting has no increase is fuel just the timeing and boost bonuses. It would be nice for road trips and highway time.



One last thing. Having read all a can on the IAT issue, it is possible to have a clean IAT that is not sending the right electrical signal. They are relatively cheap and if you have uncharacteristicly low MPG it might be a cheap way of getting some great results.



I hope some of this is helpful



Ted

 

[Ted Constantine]

check out this thread

 

[CUMIN2pass]

Thanks Ted for the insight. My truck is getting about 13-14 mpg in city with keeping it under 2000 rpm. I have found out my lift pump is below 10 psi at idle. I will get this fixed 1st an check mpg.



You talked about boost hurt fuel mileage did you mean using the right foot made it worse or that boost itself was bad. I'm going to read issue 33.

 

[Ted Constantine]

The article I was talking about is on driving with you gauges. It talks fuel to make boost, right. So the lower you keep the reading on your boost gauge the less fuel you have added to the engine. It is just another way of monitering your right foot. It also talks, I think, about EGTs and economy. The engines are most efficieny as per fuel at or under 600 degrees. It is possible I am mixing together info from more than one article but Patton's article on page 28 of issue 33 is very good and common sence. These statements assume a healthy engine. If you have an exhaust leak or boost leak you are loosing mileage based on adding to much fuel for the air avalable. In that case you will be blowing a lot of smoke. You don't get to blow smoke until you have the 275s and EZ in there . You may still want to go for a modified turbo later for EGT reasons, smoke control or just because you will be unable to keep yourself from the effects of the bombing bug



With 13-14 in the city I would go spend the 20 bucks and get a new IAT sensor. Even if it does not change anything you then have a spare. It should improve your MPG for sure. I also think one of the characteristics of a bad iat is excessive time for cooling down.



Ted

 

[Ted Constantine]

CUMIN2pass



Just for reference, with my set up on bigger tires with 4wd and 4. 10s I get 18-19 around town and even better if I pay attention to my driving. You have other problems if your 2wd is getting that low get everything checked out before you bomb.



What is your max boost now?

Max EGT?

do you blow smoke?



Ted

 

[CUMIN2pass]

My boost 10 -16 on fast take off. I have very little smoke. My truck does run much hotter than my 92 did. If I start it at idle it runs 325, around town start and stop 600 to 900. If I punch it it goes to 1000 - 1100. I think after what you said the iat is getting replaced today. Thanks for the help.