Difference in power between 2.8 and DOHC

[tsovociti]

Hey guys, i noticed that not all vr6 engine covers are the same, some hav dohc engraved on them and some 2.8, is there a difference between the 2 motors or is it just the covers?

[Mk3 AAA]

DOHC is the so called OBD 1
2.8 is the so called OBD 2
As far as I know the only real difference is the ECU set up (the later version has a diagnostics port inside) and the throttle body is a more efficient design. Apparently there's a lot less sensors on the early one
I would say the main reason for changing covers is that DOHC is kind of a lie, seeing that it's only single cam per bank, and just because the banks join at one head doesnt make the engine a straight six, being a staggered six it's a grey area, but VW stretched their poetic licence a bit there.

I don't know about dyno results, but on paper both produce 128 killa wasps, and they feel similar to drive, and in a boot from the lights theres little diff', if anything I'd say the later model (2.8 stamped) has a stronger mid range.

There's actually another few covers, one with a boarder and that's the jap spec ones, and one with a Ford badge, this went in the transit and the probe, neither came to Aus' in that spec.

[tsovociti]

We get the DOHC and 2.8 Japspec motors here... so would the motors be able to run off the same ECU? a friend of mines DOHC motor has gone to heavan and the import ones for sale are the 2.8 with the borders. Would he be able to run the motor with the dohc ecu or would he have to source the OBD2 ecu?