Giles injection pump- how good are they?

[Sansocal]

I have read nothing but good things about Giles injection pumps.. however I am still skeptical that the vw 1.6 diesel turd can make any power without a turbo. Does anyone have some data to give an idea of the real world performance of a 1.6 na with a Giles pump in a mk1 rabbit? Data like: dynanometer sheets, max speed (and what transmission you have), able to break the tires loose?

[TimpanogosSlim]

I didn't think anyone was using them without turbos?

[Sansocal]

I didn't think anyone was using them without turbos?

It's a strange world we live in !   

[TimpanogosSlim]

I'm being simple here, but aside from timing considerations (and giles has certainly considered timing), diesel power is about more fuel, and more oxygen to combust with that fuel.

If you just add fuel to an NA engine, you just make more smoke. You need to add oxygen too. The safest way to do that seems to be forced induction.

[theman53]

Burn your money did it and made IIRC around 60whp with a very old engine. No other mods other than bolting on Giles NA pump.

[Sansocal]

Power in any engine comes down to torque and rpms.. I think what Giles must do is get the little torque these engines have to be more available throughout the rev range..

[TimpanogosSlim]

Power in any engine comes down to torque and rpms.. I think what Giles must do is get the little torque these engines have to be more available throughout the rev range..

yes but how? timing curve only goes so far.

I live 4700 feet above sea level and have no interest in NA diesel in this thin atmosphere, so it is academic for me

[burn_your_money]

http://www.vwdiesel.net/forum/index.php/topic,14734.0.html

It's about as good as a stock turbo but better mileage and better throttle response.

If you have the money get both.

[Sansocal]

http://www.vwdiesel.net/forum/index.php/topic,14734.0.html




It's about as good as a stock turbo but better mileage and better throttle response.

If you have the money get both.

👍 great thread, that should be a sticky.

 I like how Giles asks you about your mods on you car and what your plans are, it shows that he really knows what he's doing and being responsible by not just "throwing fuel" at your engine which could eventually hurt it.

[Renax]

I've just turned the fueling  up a bit on mine, a lot to gain with just a little bit smoke.
Combined with modified governor it's powers are seriously improved, never dynoed, seems unnessesary with under 100hp...

[RabbitJockey]

i think the key is that he optimizes fueling and timing, the major leap in power comes from the governor mods and proper timing curve that allow these engines to make power at higher rpms, where the normal pump lets the engine start to fizzle out around 3000rpms, giles allows them to pull to red line.  but i think its also notable that on tylers dyno the giles pump more power through out the entire power band, not just at high rpms.

[vanbcguy]

When these cars were sold new they had to meet NOx emissions requirements. 

Quick little NOx primer that probably nobody cares about:

NOx is created when the Nitrogen and Oxygen in our atmosphere react.  They exist in a 'stable' state in the air, but they will combine to form oxides of nitrogen (NO, NO2, etc) when air is exposed to pressure and heat, such as during the combustion event in an internal combustion engine.  The higher the peak cylinder pressure and temperature the higher the NOx levels.  However higher combustion temperatures provide more complete combustion of the fuel (reducing CO and hydrocarbon levels).  The tuning for an engine is a knife edge - raise the pressure/temperature and the NOx levels increase, but CO and HC levels decrease.  Lower the peak pressure to get NOx under control and you lose some of your combustion efficiency, creating more CO and HC plus losing some of your power output.  Ignition timing is DIRECTLY linked to NOx levels - the more advance you apply (be it a diesel or gas engine) the higher the NOx levels.

As a result the timing curves on our pumps are conservative, they give up peak performance to keep NOx levels in check.  There's nowhere in North America that I'm aware of which actually does do an e-test that includes sampling NOx levels from mechanical diesel engines so this is purely a compliance check prior to allowing new cars on the market.  As soon as you do the typical "time your turbo pump to 1.05, it'll run the best there" that most of us do on here you've undone that initial tuning that VW did to meet the emissions regs in an attempt to get the timing where it needs to be.

Giles totally changes the timing curve, including going to the extreme of machining the pump body to allow more total advance on his pumps.  He is setting things up for the actual optimal combustion efficiency (and therefore maximum power output for a given amount of fuel) - this usually results in an economy increase as well as a power increase.  He can do fun things like set it up for low static timing (giving a quiet idle) while adding lots of dynamic timing (giving more power).  The Bosch pumps have a load dependant timing circuit internally too, which can add timing under certain accelerator positions versus RPM; that is another thing Giles can tune.

That's the stuff he does that you can't duplicate on your own without a pump calibration bench.  And that's what makes his pumps worth the money, since there's barely anyone out there that can do what he does.  It isn't a 'set the pump up to the specs from Bosch' so much as it is "have a thorough understanding of how diesel combustion works, the tradeoffs the original automaker made and the effect of changing values on that specific engine".  Even if you DO have a calibration bench, how many iterations will it take you to get all of the variables JUST RIGHT?

[Jetmugg]

As far as I'm concerned, there are only 2 guys on the planet who are qualified to do this kind of work.  Giles is one.  The other is Goran Lindgren at Dieselmeken AB.

Steve.

[Gizmoman]

I think it's already been mentioned but to clarify. . .
Giles has what it takes (knowledge and tools) to set up your pump for your specific parameters, it's important to know what those are and to let him know as well. For example, I gave him my pump and told him it was an AAZ in a Vanagon with a K-14 turbo set to 12 psi. The head had a mild port job done and I was looking for 120 or so HP.

The pump I received back was fine but I ended up changing the turbo to a HE 200 and am running close to 20 PSI max. As he built it for the 14, it can't produce enough fuel for the HE 200so I tweaked a screw or two to help. It's better, but it's not what Giles would have done had he known "new" the turbo specs. I'd send it to him again (yes, he's that good) but I simply can't afford it.

Just sayin', make sure you know where your headed before you plunk down the coin.

[burn_your_money]

Jim, have you talked to Giles? I think he will retune a pump for significantly less than a rebuild if you need it reconfigured.