D2 S8 AQH (ME7.1) ECU Vs C5 S6 AQJ (ME7.1) ECU

[MikkiJayne]

Originally Posted by Nollywood

The S6 motor is mechanically similar to the S8, the S8 has a more aggressive intake cam, more lift and duration. Pistons are the same, heads are different. Both run the same dual-stage intake, same as the D3 4.2, which shares cam shafts with the S8, I can't remember which.

Inlet cams are the same part number (077 109 012FR) for all the 40V 'S' engines - AQJ, ANK, AQH, AVP and BCS, ditto the cylinder heads. I've yet to find a single difference between the S6 and S8 apart from the mounts. I spent a lot of time researching that before buying a new AQJ to replace my sick AVP

The AQJ and AVP definitely have a single stage manifold. Two flaps, two actuators, both plumbed in to the same solenoid via a T-piece. I'll post a pic later. The manifold looks the same, but both sets of flaps are activated together. The wiring diagrams show the same iirc - two solenoids on the 'A' engines, one on the 'S'.

I would have suggested loading the manual software on to an auto ECU, but I guess its too late now!

[Nollywood]

There are lots of different files floating around for the manual S engines, and the results in terms of drivability vary. I had to replace my ECU regardless, as it is ME7.1.1. The cost of used is at least 50% of the cost of new (exchange). Besides either coding the immobiliser out, or programming my keys to the new unit, and enabling cruise, it's plug and play.

[MikkiJayne]

Fair enough Which part number did you go for in the end?

Are you deleting the SAI? I've removed the hardware from mine but not sorted out what to do with the ECU yet.

[Nollywood]

4D0907559G.

I'm keeping the SAI, no deletes. I'm building this as a high-spec B5, like it might have been built by Audi. Bodywork is next, still waiting on the last part of the B5 RS4 panels - the O/S rear quarter panel. Still on back order till the 21st May.

My other B5 V8 is going to be boosted, gutted and quite raw, but still a road car.

[Nollywood]

The V8 40V engines in the A car (C5 / D2) have 3-stage intake manifolds, controlled by 2 solenoids.

The V8 40V engines in the S cars (C5 / D2) have dual-stage intake manifolds, controlled by a single solenoid.

The D3 40V engines in the A8 3.7 have 3-stage intake manifolds as in non-S C5 / D2 40V engines.

The D3 40V engines in the A8 4.2 have dual-stage intake manifolds as in S C5 / D2 40V engines.

The V8 40V engines in the C5 RS6 have a single-stage intake manifold.

[Goran]

I dumped my SAI, as far as I understand it its only use is to help extend the life of stock cats. Well my stock cats are toast anyway, rattling like crazy.
I seriously doubt that decent 200cel or less aftermarket cats need a SAI to blow air into them to warm them up

MRC charged me only £150+VAT to code out SAI and post cat lambdas. Plus another £68+ VAT to remove the SAI, but that's easy enough to do yourself. I plastic welded the Airbox holes myself.
Neatens up the vacuum piping quite a bit.

PF S8 didn't have SAI, or the post-cat labmbdas. Damn those emissions regulations

[nakata]

Originally Posted by Nollywood

S6, ME7.1 manual.

Write me on PM

[Nollywood]

All up and running, I'll post videos later.

It's been one hell of a journey. To my knowledge, there is no other B5 A4 of any year, with a BFM V8 engine swap. It's been more Research & Development, a journey of discovery. Hopefully by next week, I can book the car in to get it tested, and back on the road.

My B5 A4 2.5 V6 TDI Quattro Sport is next. As the motor is up for sale, as soon as it's paid for, stripping of the car will begin.

[Nollywood]

A big shout out goes to the big boys and girls at A8 Parts, for all the valuable parts supplied. I would not have been able to complete this project without their help with the little parts that make any project complete.

Thank you so much, David, Carl, Maria and any others who's names I don't recall. I appreciate you all.

[MikkiJayne]

Ooh nicely done Custom radiator by the look of it? Or modified off the shelf one?

Apologies for my bad terminology on the manifold stuff by the way - I'm referring to 'single stage' meaning a single change-over point, where clearly that would lead to two different stages in the manifold. Duh. I'm claiming a 'senior moment'

from me too for the team at A8 Parts. I wouldn't even have bought another D2 if it weren't for them