Author Topic: N/A pump for k14 application  (Read 2226 times)

October 30, 2014, 02:39:51 am

FrankenDiesel

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N/A pump for k14 application
« on: October 30, 2014, 02:39:51 am »
Sorry if this is been asked for,  I just haven't had luck finding the article that I remember reading before. I have a N/A 1.6 that the previous owner bolted A k14 turbo onto. One thing that I didn't like was it smoked anything past quarter throttle and I even adjusted the fuel screw. I'm looking to reseal the pump and rebuild it because I got clogged with bad gas/diesel. I know this is going to cost a pretty decent amount but I was just seeing if I should scrap the idea of using in and a pump for a turbo diesel application.

From what I recall the turbo diesel injection pump has its boost enrichment which helps fueling on the boost curve as opposed to just always staying fat. I noticed anything above 12 psi, I ran about 18 on the set up, just pretty much smokes more and didn't really yield much performance. I'm just looking to get the best economy, performance, and lesser smoke out of my set up.

As for the performance, I'm looking to run about 20 to 22 PSI regularly with the front mounted intercooler.

Reply #1October 30, 2014, 01:09:41 pm

vanbcguy

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Re: N/A pump for k14 application
« Reply #1 on: October 30, 2014, 01:09:41 pm »
Performance-wise you can achieve about the same thing with an N/A pump as you can with a turbo pump.  The big difference is the turbo pump has an LDA (or boost enrichment valve in english) which gets a boost signal from the intake manifold.  It reduces maximum fueling until it sees boost from the turbo, reducing smoke output.

If you don't have an intercooler presently then it makes sense you didn't get any improvement with increased boost.  12 PSI is about the limit for unintercooled boost - anything more than that and the air coming out of the turbo is so hot it removes the gains of the extra air.  Around 18 PSI with an intercooler on a K14 is pretty much the best you're going to get. 

Economy and performance can go hand in hand - a big intercooler keeping boost cool will allow for an efficient burn.  The problem is when you have the extra power available you might find you have a hard time not using it!  The nice thing with diesels though is most of the changes that increase power potential also improve fuel economy generally speaking.

A turbo pump with an LDA is a direct swap for your existing NA pump.  There will be a little bit of a clearance issue with the injection lines but you should still have enough room to get timing set appropriately.  Once you have a pump with an LDA you should be able to back off the fuel pre-spool reducing your smoke output big time.
Bryn

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Reply #2October 30, 2014, 04:32:23 pm

TimpanogosSlim

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Re: N/A pump for k14 application
« Reply #2 on: October 30, 2014, 04:32:23 pm »
LDA = LadeDruckabhangiger Anschlag

It cuts maximum fueling off boost.

without the LDA, you are basically running like an ecodiesel. not a problem.

Reply #3October 30, 2014, 06:22:31 pm

FrankenDiesel

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Re: N/A pump for k14 application
« Reply #3 on: October 30, 2014, 06:22:31 pm »
So the actual useage of an na pump only yields these flaws essentially: more smoke at non boost applications which in theory is reduced economy. The turbo pump just runs it leaner at non boost applications but once boost builds, the diaphragm opens from the vacuum line applying boost in the manifold to the pump to increase fuel.

Essentially the turbo and an pumps stock can output the same fueling just the turbo pump is a bit leaner and more economical? Correct?

If that's the case I do not really see the advantage of shelling another 500 for an ip that produces less smoke.. It's my way of telling tailgaters to back off :)

Reply #4October 30, 2014, 06:46:05 pm

TimpanogosSlim

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Re: N/A pump for k14 application
« Reply #4 on: October 30, 2014, 06:46:05 pm »
Essentially the turbo and an pumps stock can output the same fueling just the turbo pump is a bit leaner and more economical? Correct?

Not really.

The LDA allows you to turn up the maximum fueling without smoking excessively when you are not under boost.

You can install a turbo w/o the LDA and w/o adjusting the fuel screw at all, and you will just run lean under boost. Which is not the kind of problem it would be on a gas engine.