4.2 V8 Coupe Quattro

[Rubberdubber]

Wow, I know it's not running right yet but that had the hairs on the back of my neck standing up, shades of American muscle car, love it

[Vorsprung durch Technik]

That's great news congratulations.

[Error404]

Well done mate, always a big milestone

[ajax1976]

Thanks all, hearing it running was certainly the highlight so far of this journey!!

Could do with some advice from you guys regarding my next modification?

Basically I was keen to make the change to TFSI coils so did some research but didn't really find anyone who had or any info on converting an ABZ or AHC. On the face of it there didn't seem to much difference between my old coils and the early VW 1.8t and Audi 2.7s etc so bought some coils, converting plates and the plugs etc to wire them up.
Once test fitted I discovered they are about 20mm short of connecting on the plug, nightmare!! I had a quick look to see if I could find a longer plug to gain some length but the V8 uses a tapered plug so gave up looking fairly quickly. Without the plates they were close but obviously there wouldn't be anything to secure the coil and cover up the plug recess, I chopped up the plates a bit so as to let the coil drop down as far as poss but still secure the coil. The coil is still a bit short so came up with an idea of extending the terminal nut on the plug, is this a crazy idea?

Plug with brass M4 standoff fitted,



Turned it down a bit with a drill and a file,



And it seated in a coil,




The top of the plug is still shrouded by the rubber section in the coil so I'm thinking it should be ok or have I wasted a wad of cash and just go back to the old style coils?

Other than that I've been getting messed about regarding the exhaust so thinking about investing in a TIG machine and having a crack at it myself. I've not Tig'd since I was an apprentice and even then someone else set up the machine for us and it was only using flat plate but I was pretty good at it, or so I remember anyway!!

In the mean time I've been cleaning the motor up and painting bits and bobs to get it presentable, finally mastered a uniform finish with VHT wrinkle.

[Rudpavv]

I love it. I want one.

[quattrostyle]

Awesome!

[newsh]

The spark plug extension is very creative but I’m not sure if the metal part of the coil pack should be grounded to the plug.. Does it run ok like that?

[ajax1976]

Thanks mate. That’s what I’m not entirely sure about and why I haven’t hacked up my harness yet to wire them in, I was hoping someone might enlighten me before committing.
The TFSI coil has 2 earths, one to block and one to the ecu so not sure if it’s related to that but on my set up I’ll be wiring both earths to the block so hoping it’s not critical for the tube to connect to the plug.
The weathers stopping play today but might try making up temp wires to connect the coil to my harness and see if I can get a spark

[newsh]

I reckon it will run but screening will not be perfect.

[ajax1976]

I hope so, I do have a last resort plan of how to extend the coil tubes, hopefully won’t come to that

[LSG]

How many wires are on each coil ? . If it's only got two wires the one from the ecu must pulse live . You can't have two earth wires fella. Please be careful you don't damage your ecu coz that would be very upsetting for you and everyone else watching this thread. Good luck. Regards Lynn

[ajax1976]

My old V8 coils have 3 wires, 12v supply, Earth to block and a trigger but the TFSI ones have 4 wires, 12V supply, Earth to block, trigger and an ECU earth.

From what I've read most guys in the VW world combine the two earths and take them to the block, this is obviously easier and my preferred option.

If I run the ECU earth separately back to the ECU I'm going to have to open up all my loom again. When I wired up the standalone ECU I ran a separate earth direct to that from the batt and most of the other sensors use that instead of the chassis earth to keep them away from interference from the coils etc so it doesn't seem quite right to connect the new coil earths on to it as well if that makes sense.

For the guys who have converted your 5 pots to TFSI coils, What have you done with the two earths? Combined them or kept them separate?

[[sTeeWie]]

Very nice project
I made the conversion to V8 in 2014/2015.
I hope with you the water cooler is sufficient.

[ajax1976]

Very nice project

I made the conversion to V8 in 2014/2015.

I hope with you the water cooler is sufficient.

Thank you!!

Huge fan of your car, it was one of the main reasons I decided to do the same.

I am starting to have major doubts but I can only try it and go from there, If I'm honest I really think I'll be looking for a larger one soon.

[geryS2]

super job, what a dreamcar you got !