Audi A6 Avant 2.5 V6 TDI Quattro

[adamss24]

Well done mate, do you have pictures of how the turbo is mounted ? What you use to adapt it to the AKE manifold and what shape is your downpipe ? I have a few more Bhp and torque than you have but i also have larger nozzles ! Do you suffer of fuel starvation in a hard drag race ? Any more mods to the engine ??

 

[doktorec]

i drive now +75% Nozzles and gtb2260vk(1,95bar) in my AKE
result is 287hp and 580Nm

If you wan't more power you can start with 4bar map sensor 2.3bar boost.
You can make hybrid turbo GTB2266VK and +120% nozzles and 2.5bar boost.Soon I'll know what is the real power with this setup.

ps.Do you use stock intercoolers?

 

[sali87]

the setup is over 3000U/min smoke free. programmed 54,5mg/h to 4850U/min.
pump is limited.
other mods are cat delete....and no muffler, Fmic
0-200km/h in 21-22s, last weekend I was the first time in my life on a 1/4 mile... with warm intercooler 1.8bar(smoky) I had a 14.4.
https://www.youtube.com/watch?v=R3iA4uBV1c0
I have a bigger Pump head for 3-Plunger pumps, which I want to test in the next days.. I have a 2-plunger pump...

 

[doktorec]

Good.But needs fuel.Why don't you remap it when you go to drag- max fuel and 2.3bar boost.I didn't understand which is the limiting factor-remap or nozzles.What is the engine code?

 

[sali87]

i built the nozzles a few hours befor the drag race. fuel is max, because of the limited vp44.
it´s an AKE in 2002 A4 B6 8e.

 

[doktorec]

If the fuel is max with +75% on AKE,and it is on 1.95 bar you need bigger nozzzles.The car doesn't smoke a lot on the video.
You can't tweak VP44 to inject more.The only way is nozzles.
We are curuntly testing +120% and for now they are holding fine.Soon we will dyno the car.

 

[diffas]

I had max 290hp and 490nm with oe Bosch dsla143p970 nozzles. I'm pretty curious about the power with the doctorec 018 nozzles that are about 25% bigger. 300hp should be able without smoke.

 

[blackquattro]

At which opening pressure did you set the dsla143970 injectors ?
I have R683 from bosio but need to find longer pins to up the pilot opening from 180 to about 240 bar.
Installing an adjustable throttle pedal bracket that keeps min throttle position at 1,8% keeps the idle stabilisation quiet and gets rid of idle shudder, 960rpm stable, also with aircon off :-D

Which flywheel and clutch are you running ? My search for a single mass unit didn't bring anything and I am affraid a new dmf with sachs performance clutch won't keep up for long either. Thinking of welding it together and using a sprung disc with sachs clutch.

Any problems with stretching headbolts, lifting heads with boost pressures of around 30 psi ?
There is not enough room for studs/nuts to clear te cams I fear.

I am running out of fuel when doing a 1/4 mile race, engine dies, air in the Vp44, also the swirl pot is almost empty. In tank pump is ok, dismantled it, not dirty. Tested it, delivered 320l/h @ 13,5v so ok.
Did any of you modify the fuel delivery system to the VP44 ?


B.R

 

[Scott_DeWitt]

235 bar

 

[diffas]

At which opening pressure did you set the dsla143970 injectors ?
I have R683 from bosio but need to find longer pins to up the pilot opening from 180 to about 240 bar.
Installing an adjustable throttle pedal bracket that keeps min throttle position at 1,8% keeps the idle stabilisation quiet and gets rid of idle shudder, 960rpm stable, also with aircon off :-D

I'm currently running around 240bar and that's just way low cause I have same idle problem as you. Something like 260-270 probably will do the trick. I had earlier Bosio 143p970 nozzles and no problem with those. Looks like the Bosch nozzles flow bit more than Bosios.

Which flywheel and clutch are you running ? My search for a single mass unit didn't bring anything and I am affraid a new dmf with sachs performance clutch won't keep up for long either. Thinking of welding it together and using a sprung disc with sachs clutch.

Stock flywheel with sachs race engineering clutch with about 50000km so far and no problems.

Any problems with stretching headbolts, lifting heads with boost pressures of around 30 psi ?
There is not enough room for studs/nuts to clear te cams I fear.

I am running out of fuel when doing a 1/4 mile race, engine dies, air in the Vp44, also the swirl pot is almost empty. In tank pump is ok, dismantled it, not dirty. Tested it, delivered 320l/h @ 13,5v so ok.
Did any of you modify the fuel delivery system to the VP44 ?

As far as i know theres is no problems wirh headbolts and lifting heads with current setup. I've running over 2bar of boost with no problems...well higher emp is what I'm concerned. With too high emp the exhaust valves will float.

I had similar problems with my pump and I send it for repairing. Dont remember what was worn out but after that everythng has been fine. I also changed the type of fuel filtering. So far everything is fine. I'm thinking to put on external lift pump, same kind they use with cummins engines.

 

[LongJohn]

the setup is over 3000U/min smoke free. programmed 54,5mg/h to 4850U/min.
pump is limited.
other mods are cat delete....and no muffler, Fmic
0-200km/h in 21-22s, last weekend I was the first time in my life on a 1/4 mile... with warm intercooler 1.8bar(smoky) I had a 14.4.
https://www.youtube.com/watch?v=R3iA4uBV1c0
I have a bigger Pump head for 3-Plunger pumps, which I want to test in the next days.. I have a 2-plunger pump...

Is it possible that stock AKE heads limit air flow above 3000rpm and cause smoke?

 

[adamss24]

If you did not port your heads then i would consider doing it ! The last set of heads i ported flowed considerably better than standard and opened up a lot more up the rev range + the engine revs just like a petrol engine- smooth and fast ! I too have fuel starvation on a drag race with current set-up, looking into aftermarket lift pumps to boost flow to the vp44 pump. I do think with race nozzles the pump injects too much faster than the lift pump can keep up so it empties the baffle when stepping on it !
With my setup, clutch slips in high gear/low revs combination, i have a Sachs SRE upgraded pressure plate but not decided what clutch disc to get- i do want to keep the DMF as i had SMF before and they do munch the gearbox syncro's rather quick !

On my other pd 130 i do have a Southbend OFE rs4 clutch stage 3 and CrMoli SMF, the set-up was fine just a bit too grabby and i think it would have been a little more forgiving if it was fitted with a DMF ! I am still thinking to use the Southbend clutch and pressure plate, only trouble is the release bearing had a alloy sleeve/spacer so don't know if to use that or a standard release bearing ! Pity i don't have pictures of the bearing...

Porting a BDG/BAU pair of heads to go on a BDH engine with oversize pistons, i am using solid genuine camshafts to get rid of the hollow cams ! Does anyone know what's the difference between the injectors ? I will use AFB injectors with race 683 nozzles...

 

[blackquattro]

I a also think a decent lift pump is needed. Which one are you considering ? Fass or airdog ?
I looked into those systems but it would require drilling a hole in the fuel tank to install a bigger pickup tube or maybe better throw out the whole internals of the swirl pot
, drill a hole for new pickup tube through the lid and insert the tube to the location where the little pump pickup was. The problem that could arise is that the fuel doesn't flow fast enough to this location, which could be solved by drilling a hole in the bottom of the swirl pot. You would also need to install a resistance to replace the fuel level sender so the ecu thinks its full (428 Ohms).

I'll make some shimms for the injectors out of feeler gauges, thickness is precise and they should be hard enough. I will try to get them at 280 bar.

So with a Sachs race clutch and new dmf I should be ok, don't you have the violent vibrations from 1800-2600rpm ?

B.R

 

[Rub87]

are the injector shims round washers? maybe check on dieselcontor for shims, might be easier than feeler gauge lint

 

[blackquattro]

Hey, you are also living in belgium, I am living near Ghent :-D
Yes they are round, but the thinnest ar dieselkontor are around 1mm, that would be too much, I will have to make some 0,6mm thick.
But maybe at dieselkontor they have longer pins, I think at Bosch they calibrate the opening pressures with longer/shorter pins.

 

[Rub87]

hmm could be jep, neverer opened up a v6 tdi injector. so stock wise there are no shims at all behind the spring?

 

[blackquattro]

No, I didn't see any when I disassemble them.

I can make some shimms by cutting 0.2mm feeler gauges in 4x4mm squares, thats easily done with scissors. Then I stack them together and clamp them between 2 rods of the right diameter, the rods are put in a lathe first. Then using a dremel grinder the parts that depass the rods are removed.

I am curious about the dynoresults of docterec with 2,3 or 2,5 bar and his 125% nozzles, I fear EGT's will be too high, at this point. Water/methanol injection will become necessary.
My AKE will get one as soon as the injectors are shimmed and the gt2559v is installed.

 

[diffas]

Opening pressure is adjusted by pins. There are loads of different length pins available in 0.05mm steps.

 

[blackquattro]

I thought so, only the people working in a few local bosch centres I asked about the existance of such pins looked at me as if I came from Mars !

Do you now where to order them, bosch part numbers ,...?

Thx

 

[diffas]

You were probably visting shops that has 80s equipment and knowledge. I don't have no part number to share. Doctorec probably know bit better cause he is working with that kind of nozzles.

 

[JFettig]

I got a lot of the same looks when I was searching for proper shims
dieselkontor.de wouldn't give me a straight answer on some info on the shims I was inquiring about.

There are pressure pins that can be changed. I don't know what the internals of the injectors look like but I bet there are shims too. The shims in the 4cyl TDI's will stick in the injector. The other shim is around the pressure pin.

If you crack them open again, post some pictures.

 

[Rub87]

if the pin is a standard diameter maybe one can just make new one from tool steel? cut/grind to length?

 

[doktorec]

They must be from steel that is used in bearings.I can give you exact size of the standart pin in a few days.

 

[blackquattro]

I will open my stock injectors this week to clean them using ultrasound.
Then I can measure the pins and look if there is a cup or shimm in the injector body behind the rod.

I plan to rework the fuel supply, a separate alu 2L swirl tank in the trunk that is filled by 2 or 3 of the stock in tank pumps. These pumps sit in the stock swirl tank. the new swirl tank has a return line with pressure regulator that keeps +-1 bar on the new swirltank and thus also on the feed line that goes to the vp44. The return of the vp44 goes to the old location in the old swirl tank. The stock pumps are listed at 3bar and 320l/h, so 3 of them in parallell should be plenty to keep the vp44 happy. Any thoughts on this ?

 

[doktorec]

A recent problem that i noticed when I put bigger nozzles +90 and + 120% is that the cylinder pressure tries to lift the whole injector.And sometimes it does.Car starts to make noise like train Puf-Paf.I put 1.5mm shim on the injector before the pad that holds the injector in place.That way you
increase the pressure on the injector.I recomend that to all that try to tune the engine.The bigger boost + more fuel creates bigger cylinder pressure and the plate that holds the injector bends.

 

[Rub87]

really strange, never is an issue on 1.9 tdi with a new or annealed washer and correct tightning torque and clean sealing surface.. I would guess if the pcp is really so high the head would lift and the rod would bend

 

[doktorec]

On 1.9tdi the part that holds the injector is made by solid steel.On 2.5 its made by 3-4mm steel that is like U.I don't know how to explain it in English.When you turn the nuts that hold it it bends to a certain strenght.


Uploaded with ImageShack.us

 

[Rub87]

ok.. if its really made so weak, can't you just use 2 plats per injector? I would be scared to crack the head if you put too much pressure as what happens with 1.9 when one does not use torque wrench to bolt down the injectors..

 

[diffas]

Sounds so damn weird. That may be happen when going far far over 300hp, with those big nozzles.
I would be concerned about the cylinder pressure is that high it lift nozzles.

 

[blackquattro]

The plates that hold the injectors on the 2,5 v6 tdi are acting as a leaf spring, Rubs idea of putting 2 on top of each other would ideally double the pressure at which the injectors is lifted, simple and effective !