Injection Pump "Dyno Test" Results

[fspGTD]

I'm taking a trip to a diesel injection specialist to have my GTD's fuel injection pump "dyno tested" on a calibration test bench.  I'm going to record fuel output quantities and timing advance at various pump speeds so I can plot them versus RPM and see the characteristic curves.  I plan on posting the results to this thread as soon as I get them.

This information could come in handy to us for better understanding what's possible with simple injection pump adjustments, and governor and LDA adjustments/modifications.  The pump is from a 1984 Jetta 1.6lTD (non prestroke, 9mm diameter plunger and 2.2mm lift camplate), and has its intermediate governor spring removed, an extended throttle lever geometry to raise the revv-limiter, a full-travel LDA, and a fuel screw adjustment that has been increased to the point where the RPMs just barely return.   Basically I feel this pump is already if not close to "maxxed out" for what is achieveable with the stock 1.6lTD pump internals.



Based on performance increases resulting from these modifications (and a look at what comes out the exhaust pipe :lol: ) I predict it is kicking out a lot more fuel than a stock pump, but I am really looking forward to quantifying how much.  Stay tuned...

PS - a more sophisticated version of the "governor mod" is in the works!  It will probably not be tested in this first round however.

[vwmike]

How much does it cost to have a pump bench tested? I have an evil pump that may need to be tested.  :twisted:

[NOTORIOUS VR]

This sounds really interesting!!!

I can't wait to hear the results (ad adjustments made to get to that point!) would be nice to see what a stock pump can do!

I'll be the first to say, thanks for sharing!

 

[fspGTD]

I injection pump dyno tested my GTD Autocrosser's VE injection pump successfully yesterday!  Although it was more time/effort than I had previously expected, it was a lot of fun, and I feel that I came home with some really great data on my pump.

Cutting straight to the chase: the following graph I put together shows the results:


An analysis of the results will be coming soon, but as a quick teaser: peak injection quantity measured on my pump is 89.4mm^3/stroke, which is 208% of the stock 43.0 specification.

PS - VWMike, shop rate is $75/hr, and figure 2-3 hrs for a VE pump test.  There is a considerable amount of setup work to configure both the test pump and the test bench for each other.  Also the testing process itself takes time, as each data point is individually tested and recorded manually (IE: paper and clipboard!)

Test equipment used:



My friend Jay at the diesel injection shop took a funny video of me operating the test bench for my first time.  Anyone want to host?

[malone]

An analysis of the results will be coming soon, but as a quick teaser: peak injection quantity measured on my pump is 89.4mm^3/stroke, which is 208% of the stock 43.0 specification.

Very interesting thread/post, fspGTD.

... and in case someone else didn't notice, fspGTD's 89.4cc is a bit more than the claimed 86cc from the pump used in andy2's twin turbo 1.9TD! It's an interesting thought...

Now Andys pump from Bowmanville/Ontario:

1.9L TD pump he's setting up with twin turbo

Full boost fuel 86 cc

edit: His 86cc was probably measured when the fuel screw was in medium setting, possibly with more room to turn it up.

I also find your drop in fueling (yellow line in graph) interesting, particularly the 3,000 to 4,000 RPM range. Your new sophisticated governor mod sounds nice from what you've told me earlier, I'm looking forward to it

[RabbitJockey]

this seems to be very informative, and i dunno how comparable it is, but most people can run 20psi with out sending the pump for a nice performance build, and you just showed ur pump giving the double the fueling of a stock pump, and 20psi is about double the boost of a stock pump... just my thoughts, not really sure how accurate they are...

[Audi80]

Fine numbers with 9mm plunger. Where is that 2,2mm camplate from? Just for comparison, my 10mm pump has 100cc max with stock camplate.

[fspGTD]

Audi80 - very interesting... thanks for the info!  I assume that this injection quantity was measured also on a pump test bench?

This pump being tested has a stock, untouched "bottom end" (everything below the governor) from a US-spec 1984 Jetta 1.6lTD.  Engine code "CY", Bosch pump number 0 460 494 135, VW part number 068 130 109 Q.  

[jackbombay]

My friend Jay at the diesel injection shop took a funny video of me operating the test bench for my first time. Anyone want to host?

  www.putfile.com will host movies up to 10 MB for free.

[Mark(The Miser)UK]

I'm taking a trip to a diesel injection specialist to have my GTD's fuel injection pump "dyno tested" on a calibration test bench.  I'm going to record fuel output quantities and timing advance at various pump speeds so I can plot them versus RPM and see the characteristic curves.  I plan on posting the results to this thread as soon as I get them.

This information could come in handy to us for better understanding what's possible with simple injection pump adjustments, and governor and LDA adjustments/modifications.  The pump is from a 1984 Jetta 1.6lTD (non prestroke, 9mm diameter plunger and 2.2mm lift camplate), and has its intermediate governor spring removed, an extended throttle lever geometry to raise the revv-limiter, a full-travel LDA, and a fuel screw adjustment that has been increased to the point where the RPMs just barely return.   Basically I feel this pump is already if not close to "maxxed out" for what is achieveable with the stock 1.6lTD pump internals.



Based on performance increases resulting from these modifications (and a look at what comes out the exhaust pipe :lol: ) I predict it is kicking out a lot more fuel than a stock pump, but I am really looking forward to quantifying how much.  Stay tuned...

PS - a more sophisticated version of the "governor mod" is in the works!  It will probably not be tested in this first round however.

Now look what I've just found... :shock:
Obviously you've got the smoking under control these days; now this is what I call a spliff
Try two turns anti clockwise on the max fuel screw :wink:


http://img212.imageshack.us/img212/6227/jakesbigsmoke2zv.jpg

[fspGTD]

Mark-The-Miser: nice work uncovering that long lost pic!  I'm gonna say that shot is a mid-90's "bug in" dragrace / VW swap meet/show at Portland International Raceways.  Those were the 14 psi boost pressure glory dragracing/daily driver days.    Wyatt Markus put that picture on his popular (at the time) web site about VW Rabbits - unfortunately now gone.

But back on topic: that car was running the exact same injection pump (just different governor and LDA tuning) as the one I just tested. :wink:

Jackbombay: thanks for the link to putfile... I may give that a try!

------------------------
Pics!

The pump looks like this when it's ready for the test bench:


It gets bolted up to a special mounting plate and also gets a special input shaft drive adapter bolted up to it:


...and it get this neat timing advance measuring gizmo bolted up to the timing advance cover:


Here is Bill of Precision Pump and Injector getting the pump ready to go on the test bench:


Here is a close-up of some of the controls we used:  testing oil heater (upper left) precisely regulates temperature of the "simulated fuel" used during the test.  A super-precise tachometer is at the upper right.  Guages below were used to monitor pump vital pressures.


The blue lucas box shown earlier measured injection quantity very precisely for each cylinder and also the average quantity and "scatter" (the largest difference in cylinder-to-cylinder quantity.)

[Mark(The Miser)UK]

Mark-The-Miser: nice work uncovering that long lost pic!  I'm gonna say that shot is a mid-90's "bug in" dragrace / VW swap meet/show at Portland International Raceways.

Those were the 14 psi boost pressure glory dragracing/daily driver days.    Wyatt Markus put that picture on his popular (at the time) web site about VW Rabbits - unfortunately now gone.

But back on topic: that car was running the exact same injection pump (just different governor and LDA tuning) as the one I just tested. :wink:

Jackbombay: thanks for the link to putfile... I may give that a try.

This was the foto that Loren sent me and then blew up his computer a few weeks ago after a long time trying to revive it. I had thought it lost forever. Would make a nice poster in the workshop! (Just another couple of feet of plume next time

[RabbitJockey]

what kind of 1/4 times were you running, any time slips as i am curious about the 1/8 and 0-60 and 60' thanks!

Mark-The-Miser: nice work uncovering that long lost pic!  I'm gonna say that shot is a mid-90's "bug in" dragrace / VW swap meet/show at Portland International Raceways.  Those were the 14 psi boost pressure glory dragracing/daily driver days.    Wyatt Markus put that picture on his popular (at the time) web site about VW Rabbits - unfortunately now gone.

But back on topic: that car was running the exact same injection pump (just different governor and LDA tuning) as the one I just tested. :wink:

Jackbombay: thanks for the link to putfile... I may give that a try!

------------------------
Pics!

The pump looks like this when it's ready for the test bench:


It gets bolted up to a special mounting plate and also gets a special input shaft drive adapter bolted up to it:


...and it get this neat timing advance measuring gizmo bolted up to the timing advance cover:


Here is Bill of Precision Pump and Injector getting the pump ready to go on the test bench:


Here is a close-up of some of the controls we used:  testing oil heater (upper left) precisely regulates temperature of the "simulated fuel" used during the test.  A super-precise tachometer is at the upper right.  Guages below were used to monitor pump vital pressures.


The blue lucas box shown earlier measured injection quantity very precisely for each cylinder and also the average quantity and "scatter" (the largest difference in cylinder-to-cylinder quantity.)

[fspGTD]

Trevorbr: On your question about quarter mile times.  The most recent quarter mile test I was able to find with this car was a 16.3 @ 82MPH, which I reported in 8/2003 here:
http://www.hostboard.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=4037&t=233
My car has undergone considerable development since then however, and is doubtlessly faster in more recent configurations (perhaps into the 15's).

Ever since I bought an RPM-sensing G-tech that logs data and can generate graphs of RPM, Horsepower, and Torque in a specific gear, I have switched to using that method of testing as it give much more information than 1/4 mi testing provides.

PS - quoting a long reply especially when pictures are involved can make the thread a lot more unweildy, and difficult to read through.  I would appreciate it you only used quoting when necessary, and only quoted the portions that are relevant to make your point clear.  Thanks in advance!


---------------------------
Moving on to an analysis of the results...


I was shocked to see in the VE pump dyno, the fueling being pulled back at an earlier than expected 4000RPM.  Based on looking at the most recent and applicable hp and torque versus RPM curves I've got, and taking other factors into consideration, I thought I'd have seen the main governor spring kicking in more like around 4750 or somewhere around there.  This pump should have a revv limiter significantly higher than stock!  Even looking at the stock fueling with the early-acting intermdiate spring, fueling drops only modestly at 4500RPM from it's peak.  I don't think the main governor spring of even a stock pump is kicking in below that point!

So... the mystery is: what is pulling back fueling on my pump as early as 4000RPM?  Could it really be the main governor spring?  Could there be some other unexplained phenomena at work here?

The "ski jump" like characteristic of the fueling curve approaching 4500RPM is also very intriguing.  I'm not quite sure as of yet about what to make of this.

[16V-Sauger]

so its not what you wanted that the fuel got it's climax at 4000? am i right that this would cause the engine to run something like "lean"?