1.8Gti Kjet - What would you do?

[ELVIS]

Just cos its you I'll let that one slide

True though bruddah! (Ok,nearly) Can fit a second hand AGG (to replace like for like) for less than a very talented,and handsome might I add, engineer from Addlestone can do WBX head studs for at forum mates rates and still afford to eat

[silverbullet]

I'll be in the blue syncro with the Oettinger sticker across the back window and engine to match.

Its a lifestyle choice

[bmouthboyo]

Does anyone have a link to Gary G gti guide? I couldn't find anything in the wiki. Cheers

[garyd]

If you pm me your email address I will forward a whole bunch of info.

[bmouthboyo]

Sorry to bump this up but I just wanted to find any contacts of people on here who run the 1.8 Kjet Gti Engine in their T25. I find a lot who have Digifant but not Kjet. Interested what Gearbox they have, Fuel Pump setup etc.

Mine seems to work well but the VW pump that is for the engine is loud and I am looking to replace with something ideally silent, but not sure if I need a pickup pump for my setup. Kjet uses an accumulator so in theory there should not be swirlpot issues with the fuel tank, which I think is from the original 1.9 DG engine anyway.

Cheers

[adyjoad]

K-jet runs at a higher pressure than Digifant so you will need a like for like pump, a good one won't be noisy. If you're using the original swirl pot/pump housing from the gti then you should be able to keep your dg tank. The gti has a lift pump inside the main fuel tank but that's because the outlet is at the top of the tank. Gravity feed from the DG tank should be enough to keep the swirl pot full other than running for a prolonged period pointing downhill with a low fuel level.

[Enzo79]

Kjet uses an accumulator so in theory there should not be swirlpot issues with the fuel tank.

The accumulator is just to hold some pressure in the fuel system ready for next time you start it, without it you just have to crank it a bit longer whilst the pump kicks in and gets the pressure up, it doesn't do anything once running.

Even on K-Jets there are a few different fuel pump set ups...

The original Mk1 Golf GTi didn't have any kind of lift pump or external swirl pot, but they did have a special petrol tank which has a kind of sumped section inside supplying a nice big 12mm outlet which had a rubber elbow straight onto the pump, so it always had a good supply of fuel.

Later MK1 Convertibles and Scirocco with K-Jet changed a bit, as ditched the special fuel tank, and used more like a carb fuel tank, but added a lift pump and odd looking external swirl pot which the main pressure pump just draws from.

And just to confuse it even more, Mk2 Golfs on K'Jet also had lift pumps inside the tank, but the main pressure pump was inside a large black plastic housing which acted as a swirl pot or fuel reservoir.

Have you got any pics of the current pump set up, as should be able to tell you what its from.

For simplicity I would be inclined to stay with K-Jet as what you have is already wired up and working, you could always just use a 2L bottom end with the DX head and stick with K-Jet just like people do in Golfs, just a few bits to sort as differences in the breather, and the dizzy hole is bigger... but bits are available to sort this.

I cant believe that DX engines are all that cheap or easy to find any more, as with prices of Mk1 golfs on the up, the prices of the bits goes bonkers too.

Cheapest option will be a 2L bottom end from a Mk3 Golf, like a 2E,ADY,AGG... everyone always mentions the AGG, and don't know why the others are ignored.

If you want to run a 2L on the Digifant or Motronic its going to mean a lot of wiring, as you will need a loom and everything from the donor vehicle, and have an ECU and all that extra stuff.

[bmouthboyo]

Wow thanks Enzo that is some great information.

I actually currently have just an inline pump that feeds into the accumulator. The pump has a very small see through inline filter and is fed from the fuel tank simply by gravity.

It seems to run fine apart from the odd hickup if low on fuel, but my main concern is how loud the thing is! You can hear it over the engine and it really sounds like it is struggling at times.

I have it mounted via a bracket with rubber clamp but it still is very loud. Is this normal? Would a new pump sort this out as it appears to be an original MK1 Gti pump.

Also would it be worth upgrading the fuel pump system altogether? Maybe going with one of the Mk1 housed pumps you mentioned which has a swirl pot? Having the tank modified with a lift pump? Or would it still be just as noisy?

[Wychall]

I have a South African Microbus with the 5 pot Audi engine fuelled by KJet. Yes you can hear the pump running, if you lie underneath the bus close by it. Otherwise pretty quiet. Gravity fed from the tank by approx 1 metre of pipe. I can dig up the details of the pump later today if you want. I replaced it a couple of years ago quite cheaply.

[Enzo79]

The fuel tanks on a T25 with fuel injection have a larger outlet spigot to gravity feed the fuel pump, its to take something like 11mm bore hose rather than 7mm hose on a carb one.

It doesn't sound a huge difference but if someone want to do that maths on the cross sectional area of the tank spigot, the injection tank should have something like 2-3 times the flow rate.

On the Golfs with the lift pumps, when the pump in the tank dies the cars will still run, but the main injection pumps whine like crazy, as are having to work a lot harder to suck the fuel out of the tank.

Maybe its also happier when full, as you have all that weight of fuel on top pushing it out the bottom of the tank.

My guess is the pump on yours is working a lot harder than it should to suck the fuel out of the carb tank, and would he happier fed from an injection tank, plus if you haven't got it you want the foam sound insulation that goes round it, and mount it on some rubber bobbins like on a injection T25 to stop it from transmitting all that buzzing into the bit of chassis its attached too.

[Wychall]

Plus, pumps always make more noise when they are worn. Mine did, just before it died.

[markpark]

I've got a DX K-jet in my single cab that I've just bought - fuel pump is very noisy also. I'd be interested in seeing some pictures of where your fuel metering/distributer head thingy has been installed and if its running a golf airbox or something modified. Mine is running original golf airbox but its placed very close to the aux belt and I'd like to relocate it.

[Titus A Duxass]

It doesn't sound a huge difference but if someone want to do that maths on the cross sectional area of the tank spigot, the injection tank should have something like 2-3 times the flow rate.

The area of a circle is Pi * r2

[Wychall]

Original VW South Africa installation (apart from lpg....)

[Simon Baxter]

We have access to the fuel hose and fittings for making K-Jet injection lines if needed.