HKS Turbo Timer wiring

[Big Rich]

Hi Please can anyone help me on a technical question ? I have just bought off the dreaded ebay, a HKS turbo timer complete with bongo plug, black wire and the wire with a gray/red trace, but no instructions, can anyone give me any pointers where i can find the bongo fitted plug or where i shove it !! all answers greatly apprecated thanks for looking Richard ps the black looks like an earth lead ?

[smartmonkey]

I know you have just bought it and all that but I have to ask why do you want a turbo timer? They can be useful on high performance petrol cars but are overkill on old diesels. Keeping them ticking over when they should be off is a waste of fuel and causes wear and tear. The only time you have to worry is pulling off a motorway and suddenly stopping (i.e. service station) - best to keep it idling for 20 or 30 seconds. If you aren't dead set on it best to stick it back on Ebay.

I guess the plug you are looking for is from the ignition barrel or injector pump. It must be close to either of them.

[Ian]

Turbo timers are illegal for on-road use in the UK.

[mikeonb4c]

The only time you have to worry is pulling off a motorway and suddenly stopping (i.e. service station) - best to keep it idling for 20 or 30 seconds

Could I just ask. If I pull of the m/way having done 65-70 mph (i.e. rpm not above 2500), lift off throttle to decelarate up slip road, stooge up to a parking place, then switch off (i.e. follow my normal practice), am I putting old Mango at risk? Or is it just the 'thrashers' who need to take care.

Your excellent advice welcomed as ever SM, dandy (where is he?) and others.

Mike

[ICB]

Turbo timers are illegal for on-road use in the UK.

AFAIK it's just illegal to leave your car running unattended, not to have a turbo timer fitted or to use one. I know lots of people with them and don't know of anyone who's got into trouble just for having it.

Of course why you'd bother spending the money when you have to stay in the car is questionable, unless you're very forgetful.

[francophile1947]

I think you'll find it's just the "thrashers" Mike - I can't believe that a lump doing 2500rpm is at any risk. If in doubt, let it tick over for a few seconds before pulling to the pumps.

[johnzbenson]

Essentially Turbo timers came about for the Boy racer element typically quite small Turbos with a high RPM sped for the petrol 1.3 to 2 litre market the problem that came about was that after thrashing up the road the turbo would still be whizzing away for up to 30 seconds after switching off the engine without any oil being delivered for lubrication of the turbo bearings.
As previous posts have mentioned unless you are continually revving the engine high and then switching off immediatlly then a timer may not be of benefit.
Also a simple action of sitting at idle for 10 seconds while you apply the handbrake, remove your seatbelt etc will suffice for most. I think as well that Most Bongo Drivers are a steadier breed anyway.

[mikeonb4c]

Thanks franco / jonz - my question answered. It seems to me that - with the autobox - from the moment you lift off just before you enter the m/way services sliproad, the engine is starting to rest at no more than 1500rpm. So switching off as soon as you park should be 100% safe. Which is great, cos my addled brain aint gonna remember all those complicated things like waiting 30 secs etc. I mean, I'm still getting used to waiting for the coily light thing to go out before turning the ignition key (Mango lets me know when I havent waited though!)

[ICB]

Essentially Turbo timers came about for the Boy racer element typically quite small Turbos with a high RPM sped for the petrol 1.3 to 2 litre market the problem that came about was that after thrashing up the road the turbo would still be whizzing away for up to 30 seconds after switching off the engine without any oil being delivered for lubrication of the turbo bearings.
As previous posts have mentioned unless you are continually revving the engine high and then switching off immediatlly then a timer may not be of benefit.
Also a simple action of sitting at idle for 10 seconds while you apply the handbrake, remove your seatbelt etc will suffice for most. I think as well that Most Bongo Drivers are a steadier breed anyway.

Couple of points about what John says there, firstly I don't think petrol and diesel turbos per se will have much difference in the top-end RPM (probably around 40-50,000) and those fitted to diesels will typically be running at higher pressure so may actually be running faster, other factors being equal. Also they'll kick in earlier, around at around 1750 RPM vs 2,500 for a small turbo on petrol, up to 4,500 for a big one that takes longer to spool up. Having said that the turbo in a diesel is under less general stress as exhaust gas is at a lower temperature and they don't have to change speed as much due to the shorter rev range. Likewise turbodiesels, especially older ones, do tend to be more over engineered than turbo petrols and probably have larger turbos on the whole.

I don't know what turbo is fitted to Bongos, or whether it has a braided steel oil feed pipe, but even larger turbos with later spool like a Garrett T3s will benefit from a cooling down period, not just the little ones like T25.

Some of this does depend on driving style but if pulling over into a lay by after a run on a dual carriageway or in the mountains I'd be tempted to give it a minute or two, if the ambient temp isn't too hot I stick the heater on full blast as well. This is probably all a bit anal on my part though.

On a personal front I find a well tuned sports coupé is the perfect accompaniment to a Bongo and I appreciate the weight and feedback of steering, taut handling and suspension in the 200sx all the more since getting the Bongo. High performance cars can be enjoyed by the older lady and gentleman with less likelihood of planting them backwards into a telegraph pole and hence more affordable insurance.