Split-Shot Injectors - PowerStrokeNation : Ford Powerstroke Diesel Forum
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 31 (permalink) Old 10-18-2008, 05:21 PM Thread Starter
MPG Moderator
 
Dave Whitmer's Avatar
 
Join Date: Jul 2007
Posts: 1,083
Split-Shot Injectors

After about 4,500 miles of testing, I have come to a conclusion about single shots.

They do improve MPG - by about 1%.

I changed out my 218,000 mile splits for new singles from a top injector outfit. I got six different tunes as well Two of those were better than the rest.

With my old splits, I got 26.9 MPG summer mileage on my normal loops (35% urban, 35% two-lane road, 30% Interstate - all driven at posted limit or close as I can get). With the single-shots I averaged 27.3 with the two best tunes. I obviously have not tried them in winter yet.

I have not monkeyed with my aero package since starting the injector test.
Not a drop of additive of any sort has gone into the tank since starting the injector test.

Oddly enough a tune approximating a commercial performance tune did quite well once I changed my shift points. Normally I shift at 1200-1300 RPM. For his fangs-out MPG tune, this worked well, but for the performance tune it made my truck smoke like a steam locomotive. By shifting at 1800 RPM (high RPM for me) the turbo perked up and the smoke cleared. When all was said and done the two tunes gave with 0.02 MPG of each other. My margin of error is usually about 0.3 MPG.

Make of it what you will.

2000 F-350 SC 4x2 6 speed
3.08 gears Gear Vendor Overdrive
Slammed 4"
Rugged Air Dam
315,000 miles

Last edited by PTSUPERD; 10-20-2008 at 01:37 PM.
Dave Whitmer is offline  
Sponsored Links
Advertisement
 
post #2 of 31 (permalink) Old 10-18-2008, 05:46 PM
PSN Veteran
 
Join Date: Aug 2007
Location: chocolate city, LA
Posts: 7,358
Send a message via AIM to slowleak
Re: Split-Shot Injectors

i think you shoulod go one size up on the gears. let that turbo spool a little more. all you are doing is wasting fuel down low IMO. who tuned it and what injectors were they?

2005 F350 prairie tan/black crew cab FX4 innovative tunes, exhaust

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
PMRCM#1
slowleak is offline  
post #3 of 31 (permalink) Old 10-19-2008, 07:03 AM
 
Join Date: Jul 2007
Posts: 2,085
Re: Split-Shot Injectors

You say at first splits give better economy and then you list mileage numbers that say your new single shots give better economy?
69W900A is offline  
 
post #4 of 31 (permalink) Old 10-19-2008, 02:18 PM
PSN Veteran
 
matthewd11's Avatar
 
Join Date: Nov 2007
Location: Rhode Island
Posts: 4,729
Re: Split-Shot Injectors

I noticed that earlier, but i wasnt going to be the first to say something

07 CCSB 4x4 Lariat FX4 Bronze Metallic/Sage
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
matthewd11 is offline  
post #5 of 31 (permalink) Old 10-19-2008, 05:38 PM Thread Starter
MPG Moderator
 
Dave Whitmer's Avatar
 
Join Date: Jul 2007
Posts: 1,083
Re: Split-Shot Injectors

My bad. Let's get it clear: Single shots give better MPG than split shots. That clear enough?

The fact that a fangs-out MPG tune and a more or less performance tune gave about the same MPG (although they require different driving techniques) leads me to the logical conclusion that the tune is irrelevant to MPG.

What I want no part of is a contest of commercial loyalty - "A's stuff is better than B's stuff."

2000 F-350 SC 4x2 6 speed
3.08 gears Gear Vendor Overdrive
Slammed 4"
Rugged Air Dam
315,000 miles
Dave Whitmer is offline  
post #6 of 31 (permalink) Old 10-20-2008, 02:02 AM
Precision Planting Dealer
 
Deereman4020's Avatar
 
Join Date: Oct 2008
Location: Horicon Wi or Platteville Wi
Posts: 670
Re: Split-Shot Injectors

Man thats really incredible the mileage you are getting out of that truck. Keep up the good work.

1994 F-250 7.3L PSD reg cab long bed 5spd 4X4 6637, home brew stack and SD fuel system Jacob
Farming isn't a job or a hobby. It's a way of life. A way of life that no matter what, some people just can't let go. I'm one of those people. Those proud to be a reliable American farmer!!
PM me for precision planting parts.
Deereman4020 is offline  
post #7 of 31 (permalink) Old 10-20-2008, 02:47 AM
2010 BOB Points Runner up
 
Dieselfever's Avatar
 
Join Date: Aug 2007
Location: Beaverlick, KY
Posts: 2,300
Send a message via AIM to Dieselfever Send a message via Yahoo to Dieselfever Send a message via Skype™ to Dieselfever
Re: Split-Shot Injectors

Good to hear Dave! So far you have picked up around .4 mpg so far.

I understand what you say about the comparison between the 'made for fuel economy' program and the performance program. I have similar results with the same scenario in my '95 between the 'all out power' program and 'made for fuel economy' program where they net about the same fuel economy. I guess that might be the nature of these beast even with the different tuners.

-Michael

Michael

1997 F350: Regular cab XLT, 7.3L PSD, 5 speed, 4x4, 3.55 - Some Stuff
2000 F350: Crew Cab, Lariat, 7.3L PSD, 6 speed, 4x4, 3.73 - More Stuff
2001 VW Golf: 4 door, GLS, 1.9L TDi, 5 speed - Darn near makes fuel!


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Dieselfever is offline  
post #8 of 31 (permalink) Old 10-20-2008, 06:29 AM
 
Join Date: Jul 2007
Posts: 2,085
Re: Split-Shot Injectors

Quote:
Originally Posted by Dave Whitmer View Post
My bad. Let's get it clear: Single shots give better MPG than split shots. That clear enough?

The fact that a fangs-out MPG tune and a more or less performance tune gave about the same MPG (although they require different driving techniques) leads me to the logical conclusion that the tune is irrelevant to MPG.

What I want no part of is a contest of commercial loyalty - "A's stuff is better than B's stuff."
Tuning can make a big difference in MPG, but as you've pointed out there are many variables. I drive the same way pretty much all the time. I don't have an econo tune so I drive around in either my tow program or my "race" program. The race program consistently drops the economy about 1.5-2mpg over my tow tune just because of the aggressive nature of the fueling. This is all unloaded.

Along with driving habits good tuning should make a big difference in MPG.

I am a little confused about your comments on timing earlier in this thread. You seem to indicate that advanced timing makes the truck hard to start when cold. Advanced timing actually makes the truck easier to start cold and at the point the you have advanced the timing so much to make it hard to start it'll hard start all the time. In fact many mechanical diesels use weights or fuel pressure valves to artificially advanced the timing during cold starts.

Another thing to note is that on a powerstroke your cold start timing advance and hot running can be two DIFFERENT values (actually they are stock and change based on a number of different conditions dynamically). So you can advance the timing all you want hot and not cold, etc. So you should never have a cold start problem if the tuning is done correctly. This is of course assuming the timing changes are being done in the program itself, I have seen and read about people tricking the EOT sensor to change the timing tables and that is not the best idea.

All else aside, areodynamics and the driver are the two largest MPG factors. Well that and the large box of dead weight that is usually following my truck nearly every time it leaves the driveway
69W900A is offline  
post #9 of 31 (permalink) Old 10-20-2008, 01:20 PM
Banned
 
Join Date: Jul 2007
Location: Twilightzone
Posts: 7,764
Re: Split-Shot Injectors

I'm not being argumentative, but when I see 12 valves having a hard time starting it's because they have the timing advance set to meet the needs of the engine at full power in the higher rpm ranges and it just doesn't want to crank anymore with that much advance.

If they could retard the timing to crank it would help them. My truck cranks best at ~3 degrees advance. Course I'm sure with the lowered compression mine likes less timing than some others.

Seems like when it's cold, spraying the fuel into the cold cylinder even earlier is just going to stiffle that cylinder's ability to gain heat. Make a lot of blue/white smoke and snuff it out. Waiting a bit would seem to give the air a chance to compress farther toward TDC, gain more heat and ultimitely have a fighting chance at igniting the fuel.

Now that's just based on my observing hot rod mechanical trucks trying to crank with what is a lot of timing for idle rpm, and what I've noticed on my truck with lowered compression. So I could be missing a big portion of the puzzle and just not realize it.

Ever hear a 12v guy say, I would like to advance it a bit more, but it's my Daily Driver and if I do it'll get hard to crank in the mornings?
Charles is offline  
post #10 of 31 (permalink) Old 10-20-2008, 01:39 PM
PSN Veteran
 
Join Date: Aug 2007
Location: chocolate city, LA
Posts: 7,358
Send a message via AIM to slowleak
Re: Split-Shot Injectors

can anyone explain why people with sho b-codes and extreme tuning (i.e. 600+ hp tunes) are getting 22+ mpg running at 80+ mph?

i thought stuff like that hurt your mpg, looks to me like it helped

2005 F350 prairie tan/black crew cab FX4 innovative tunes, exhaust

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
PMRCM#1
slowleak is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the PowerStrokeNation : Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome