Bosch VE Injector pump mods. (diesel power march 2008)

[tSoG-84bit]

I just got the march issue of diesel power. Had an article on tweaking an IP for pretty big gains.

Heres the text. pictures to come when I get them uploaded.

what happens when magazine guys get bored on weekends? more power, that's what. We were waiting around for gauges and some other stuff for our '89 Dodge Ram while we tried to think of a cheap way to solve our slipping transmission problem. Then we realized, "Hey we haven't turned up the rotary pump in this thing yet!" and set to work with simple hand tools to discover how much power we could get out of free injection pump mods.
First, we took off the pump top and rotated the diaphragm. This produced a power gain that was just barely noticeable on our test drive. We'd heard the big power boost was in the full fuel screw, so that was next. The screw had a collar on it from the factory to keep us from adjusting it more than about 3/4 of a turn, so we cranked it all the way in. It definitely felt faster, but there was still no smoke so we knew we could go further.
We backed the screw all they way out of the pump and put it in a vise. We used a chisel, a hammer, and a pair of pliers to pry off the stock collar (which is tack-welded on_ in order to turn up the fuel more. We were very careful not to damage the screw (too much) when doing this mod; it is a Bosch part-not something we can just run down to the hardware store and get. Once the collar was off, we could turn turn the screw clockwise for more power. But wait! There's more.
If we turned the screw too far, our engine could go into a "runaway" when it starts. The pump would keep fueling itself once the engine was started and would keep going even if we turned the key off.
Whenever we're messing with the fuel screw, we make sure to have the intake piping into the turbo off, and a 2x4 or something similar to cover the front of the turbo and stall out the engine in case of a runaway. Never, ever try to stall out the engine with a rag or your hand make sure you have something sturdy that won't get sucked in the turbo. We recommend that you practice it a couple of times to make sure you have the hang of stalling it out quick, before you get to turning the screw.


Although not as glamorous as its big brother, the p7100 injection pump (found on 94-98 cummins), the VE pump found on 89-93 Dodges can still be made to produce some good power.


Our first step was rotating the diaphragm. This is done to give the engine more fuel under boost. First, we took off the banjo-style air line connected to the top of the pump. There will be a couple of washers that like to fall out, so make sure you don't lose any pieces.


Next, we took the pump top off using a screwdriver. The diaphragm is spring-loaded, so be careful when you take the pump top off-the diaphragm will want to come with it.


When looking at the top of the diaphragm, you'll see a tick mark in it (arrow) noting it's position. Stock is 12 o'clock, or facing the engine. Ours appeared to be set about 1:30.


Next, rotate the diaphragm 90 to 120 degrees clockwise. Inside, there is an offset traffic-cone shaped eccentric. rotating it will move the offset further away from fueling rod, giving more fuel as boost rises. make sure not to over tighten the banjo air line when you put everything back together.


Our next free pump tweak involves the full fuel screw that is located at the back of the injection pump (arrow). This is where our major gains would come from. With a screwdriver and 13mm wrench, back the screw out of the pump completely so you can take the metal collar off.


This is what the fuel screw looks like after it is taken out of the pump. Count the number of turns from where it bottoms out on the collar to where it bottoms out on the screw to see where the "stock" setting is. Ours was about six turns.


Getting the collar off is a pain, as seen by our mangled fuel screw. We used a pair of pliers to yank it the rest of the way off after we broke it apart.


With the fuel screw out, slowly work it back up the damaged thread, where the collar was. We bound out that we now had 14 turns total, or about eight more than stock.


Put the fuel screw back in at one turn over stock and take the piping off the turbo to choke the engine if needed. We used the box that our old injectors were in because it was the right size, laminated, and pretty thick. A 2x4 is also a good bet; just make sure it is clean.


With the collar off, you can see how many more turns we have left on our pump (arrow)



With the pump turned up, you'll have to adjust your idle back down. This is done with the idle screw (arrow). With the fuel screw at three turns, our truck idled at 1,100 rpm in neutral, so a lot of adjustment was needed to get it back to 750 rpm. There is a 10mm nut on the back of the idle screw that is a real pain to get to. Cummins makes a 90-degree tool specifically for this, or you can just try to break it loose with a punch. either way, it's frustrating.

hope this helps.

[tSoG-84bit]

update, pictures didn't turn out very well. I'm gonna work on getting better ones taken.

[tSoG-84bit]

pictures added, sorry about the blurry one, it's a blurry picture of a blurry picture. It's the best I could do.

[jimfoo]

About what's covered in the FAQ in the make your 1.6TD a faster car though you have more pics I think.

[subsonic]

I read this whil I was on the beach.  They did do a pretty good job in the article. Good pics.  I like the part about not putting your bare hand over the turbo to choke it off.  EEEEWWWWW, that could be nasty!

Can any of these pictures transfer over and be used in the FAQ section?

[jimfoo]

I read this whil I was on the beach.  They did do a pretty good job in the article. Good pics.  I like the part about not putting your bare hand over the turbo to choke it off.  EEEEWWWWW, that could be nasty!

I just have my hand on the fuel solenoid wire myself.

[Redrum Rabbit]

I just have my hand on the fuel solenoid wire myself.[/quote]

Dodge guys say that's a no go as it'll just rip the plunger and keep on running away.  I would not use a cardboard box on a turbo with a 3 inch opening either.  chunk of wood only.  Also they don't show a pic of the boost pin or show it in its max fuel setting.  A picture of this would be worth a thousand words.  Most computer savy dodge owners know about this mod though.

I subscribe to Diesel Power and like it alot. I am however a little disapointed that there is no VW diesels in it that i've seen....  Maybe in future issues.

[hillfolk'r]

I JUST found a whole writeup,like 30 pages ,on how the bosch ve pump works!!!!its like readable gold,i was reading it tonight,and lightbulbs were going on.....
it was all training info from school,and even has specs for a  na vw rabbit pump
ill have to scan it and get it up here
in the meantime,i like diesel power mag.,,ill have to pickup a copy

[hillfolk'r]

I read this whil I was on the beach.  They did do a pretty good job in the article. Good pics.  I like the part about not putting your bare hand over the turbo to choke it off.  EEEEWWWWW, that could be nasty!

I just have my hand on the fuel solenoid wire myself.

i never trust it(soleniod),always have an open intake and a thick solid chunk of something to stall it out
i use an electrical box cover(square)
even then it wont stall out sometimes,(pulling air thru the valve guides)but run low enough  so you can think
ive seen a few diesels run away,its not funny
its not that the turbo will cut your hand,itll give you a huuge suckin blood blister!!!!

[coke]

If its a manual transmission, you could always have the wheels chocked, ebrake on, and stand on the bumper while someone gets in and dumps the clutch with the brakes on