Offroad-Express

Looking for someone who knows their arse from their elbow when it comes to n/a TD42s. A "Diesel Tuner" in Whangarei (may also be called "wizard" or "guru")

I am wanting to give it a bit more poke, without major expense (ha - ha!) The injectors are due for a once over, so it would be my intent to have them shimmed for higher crack pressure. This will have the flow on of having to up/ retard the Injector pump
- I would need someone who knows numbers etc that can be achieved on the stock IP. Preferably without an EGT (that is also on my long, long list of expenses due)
-OR- is the pump the kind of thing i can bore and spin up a new (bigger) plunger for in the lathe?

I intend also to stick an electric pump inline (at the tank) so the old mechanical isn't sucking her guts out.

I'm handy with a spanner, but have no experience diesel tuning. There was a fulla an the north shore of Auckland(?)who was going to get me a set of injectors on an exchange basis.

Any recomendations? Advices?

no point increasing crack pressure, that might cause other issues.

tuning NA diesels is tricky. you need egt gauge for it.
my understanding is they get hot really quick. also you have to figure what your leeway is. eg dirty air filter reducing air flow may be enough to cause piston/head failure. if you push the limits it doesn't take much to do damage.

with the reco'd injectors look at tweaking the timing up a tad. the old pump is probably running the timing a bit retarded.

talk to darinz he'd be able to point out a wizzard from a muppet up in the rei

tweake wrote:no point increasing crack pressure, that might cause other issues.

tuning NA diesels is tricky. you need egt gauge for it.
my understanding is they get hot really quick. also you have to figure what your leeway is. eg dirty air filter reducing air flow may be enough to cause piston/head failure. if you push the limits it doesn't take much to do damage.

with the reco'd injectors look at tweaking the timing up a tad. the old pump is probably running the timing a bit retarded.

I must ask, issues like what?

It was my understanding that higher crack pressure would lead to retarded timing, I also believe these pumps are retarded from factory (and given the state of everything else, probably untouched by p.o.) so I thought that if I raise the crack pressure and take up any slack in the timing, I'd be on the money. Or am I missing something?
OK, have to get an EGT. that will put my plans back a few months. Bugger!

MihiT wrote:

tweake wrote:no point increasing crack pressure, that might cause other issues.

I must ask, issues like what?

like a worn pump failing completely due to the extra work the pump has to do.

tweake wrote:

MihiT wrote:

tweake wrote:no point increasing crack pressure, that might cause other issues.

I must ask, issues like what?

like a worn pump failing completely due to the extra work the pump has to do.

Which brings me back to supplementing with an electric?, and can I spin this (plunger?) in a lathe or is it too much like real work?

I'm not meaning to be a smart-ass, just trying to get my head around this.

MihiT wrote:
Which brings me back to supplementing with an electric?, and can I spin this (plunger?) in a lathe or is it too much like real work?

I'm not meaning to be a smart-ass, just trying to get my head around this.

machining the plunger? very tight tolerances and rather importantly the surface finish.
realistically not worth even thinking about.

i'm trying to recall the exact effects of increased crack pressure setting has on injection spray. i will have to look it up.
but in any case its a complication that won't really achieve anything, especially on a stock engine.
afaik there is no simple trick with the injectors to improve performance without adding more fuel.

electric lift pump can help increase internal IP pressures which helps with timing.
but it won't do anything for injection pressure.

i would simply just get reco injectors and possibly the pump timing checked or even advanced a bit more.

tweake wrote:

MihiT wrote:
Which brings me back to supplementing with an electric?, and can I spin this (plunger?) in a lathe or is it too much like real work?

I'm not meaning to be a smart-ass, just trying to get my head around this.

machining the plunger? very tight tolerances and rather importantly the surface finish.
realistically not worth even thinking about.

i'm trying to recall the exact effects of increased crack pressure setting has on injection spray. i will have to look it up.
but in any case its a complication that won't really achieve anything, especially on a stock engine.
afaik there is no simple trick with the injectors to improve performance without adding more fuel.

electric lift pump can help increase internal IP pressures which helps with timing.
but it won't do anything for injection pressure.

i would simply just get reco injectors and possibly the pump timing checked or even advanced a bit more.

OK sweet, thanks.