Tuning Problems V12

[PeterCrespin]

The RB14 (same as XJ6 amp) needs a heat sink as well as an earth. Originally the inlet manifold served both purposes but placing for airflow may mean heat sink effect is forgotten, leading to shortened life.

[SESH]

Hi Pete
This unit DAB113HE was originally used on the XJS HE. SNG Barratt tech guys seemed to think it was a good solution to mount it on the picture frame. If I fit it on the block I fear it will fail again so a bit of a catch 22 situation .
Mike

[PeterCrespin]

I agree ‘Death Valley’ gets very hot, especially if an AC compressor is fitted. It eventually proves too much for 1970s components in the Opus amp, which do better up front on the picture frame. I assumed you were talking about the smaller cigarette-packet black amplifier fitted to XJ6/ XJ 12 and XJ-S, which used CEI (constant energy ignition) and was never fitted to the block or in the valley, always to the inlet manifold. This location was fine and didn’t overheat the electronics, but the finned Opus casing would have been too big to fit under the bonnet.

If choosing between my comments and Barratt’s advice, ALWAYS follow the one who’ll give you a refund if things go wrong.. x

[rossco_j]

Amplifier now re-sighted on the picture frame under the header tank.
Mounted longitudinally in front of the picture frame using a new header tank bracket.
Manufactured a metal strip to hold the amplifier using both bolt holes. Then added a dedicated earth wire to the engine block.

Looks like a good solution. I've done the same, however I would slide the module further away from the header tank down pipe. Just in case of a leak. Water & sparks never ends well...

[SESH]

Thanks all for your very helpful comments.

Pete, it is indeed the old Opus finned amplifier with new module inside.

Ross, will look at moving it along a bit but I am slightly restricted by the length of the wiring from the coil/ballast resistor.

Thanks
Mike

[Woolfi]

Why don't you mount a vented cooling system for your amp ?

You need a rubber hose form the air filter onto the amp and a second hose leading from the amp to the front of the car. If the motor is running, cold (!) air would be sucked through the amp. I can't estimate, how big the cooling effect woiuld be.

If somebody would mount this simple system, it would be interessted to know, how big the difference in temperature before and after would be.

Regards Wolfgang Gatza

[SESH]

Hi Wolfgang
An interesting idea, but for now I will run it without ducted cooling and see where we are.
I think the main issue with over heating on these units comes from heat soak, so may be ok on the picture frame away from the very high temperatures of the engine block.
Kind regards
Mike