Increase Power. Stdt Fuel Pump...

[adrian_gti 0]

Hi guys,

I've just found out my TT needs either a total rebuild or a turbo rebuild so it seems I'm stuck with the STDT for a while. I've been told about getting more power by adjusting the fuel pump but i'm not even sure where it is.. I followed the fuel pipes to a bit at the fron of the car that has more pipes going to to where the heat plugs are. Could this be the fuel pump? On it looks like a screw with a small hole in the top.

 

If this is not the fuel pump does anyone have a photo showing where it is?

 

If it is the fuel pump what direction and how much should I turn the screw for best power / smoke ratio?

 

Are there any other mods I can do to get a quick cheap power increase?

 

cheers guys.

[Anthony 1,003]

The fuel pump is the thing above the alternator that the injector pipes and fuel lines connect to.

 

I'd seriously look at an intercooler before whacking up the fuelling though - the addition of that alone should give you a fair bit more power/torque (without more smoke) and give you more scope for tweeking the pump. The engine was intercooled in the 405/BX applications as well as in Rover 218/418td models, and from memory that alone was a difference of 12hp (78 vs 90) and a similar percentage torque increase.

 

Remember that on a diesel.... more fuel = more boost = higher intake temperatures..... and on an non-intercooled engine that's not too clever

 

The method to tweeking the pump is the same as 306's (there's a guide somewhere if you do a search) although you'll need to check whether you have a Bosch or a Lucas-RotoCAV pump (as the method differs)

[adrian_gti 0]

thanks anthony. looks like it was the pump i was looking at but i'll source a intercooler before doing anything.

cheers

[Anthony 1,003]

thanks anthony. looks like it was the pump i was looking at but i'll source a intercooler before doing anything.

It's a bit of a ballache of a job though, as you'll need to remove the inlet manifold and access is pretty lousy (remembering that the diesel engines have the inlet and exhaust on the same side of the head, and which of course is the rear of the engine bay where you can't see a damned thing)

[Guest BrainFluid]

Remember that on a diesel.... more fuel = more boost = higher intake temperatures..... and on an non-intercooled engine that's not too clever

 

Does the turbo's waste gate not need tinkering with too to get it to that point? I thought the wastegate stopped the boost from getting to high. Or does the wastegate work exponentially with the added fuel/ exaust fumes thus making what your saying true? (honest curiosity)

 

 

 

It's a bit of a ballache of a job though, as you'll need to remove the inlet manifold and access is pretty lousy (remembering that the diesel engines have the inlet and exhaust on the same side of the head, and which of course is the rear of the engine bay where you can't see a damned thing)

 

Yeh, theres a 13mm bolt in the middle of the lower back of the inlet manifold to remember not just the allen bolts!

 

Plus there isnt enough room for the turbo to come out/go back in if its still attached to its manifold that goes between it and the head.

 

And then theres no room to get at the two bottom bolts that connect the turbo to its manifold, you need too half slide the pair of them joined together away from the head to get at the buggers.

 

Nate.

[Anthony 1,003]

Does the turbo's waste gate not need tinkering with too to get it to that point? I thought the wastegate stopped the boost from getting to high. Or does the wastegate work exponentially with the added fuel/ exaust fumes thus making what your saying true? (honest curiosity)

The primary thing limiting boost on diesel's is fuelling. On a standard car, you could completely disconnect the wastegate and it would make no difference at all to boost level. If you chuck more fuel in and get more boost, then yes, if the level exceeds what the wastegate is set for then the wastegate will be the limiting factor.

 

From people I've spoken to that have done this (on 306's), most of them didn't need to touch the wastegate.

[Galv 0]

I used to run a STDT and as you know I've tuned around 800 306 Dturbos

 

I would not touch the boost on an STDT until you have an intercooler, Just increase the main fuelling a little.