300tdi - More POWER!!!
Discussion
So, Ive got a 3.9L V8 manual D1, it eats fuel and has faulty electrioncs which Im fed up of dealing with.
Ive driven a couple of TDIs, tweaked, standard, etc, and theyve all been really slow and felt rubbish, but since Ill never get 25mpg from the V8, I suppose its best to look at other options.
So - Im thinking a VNT, a larger intercooler, and a dual port inlet manifold, with fuelling modifications to suit of course.
How much power can I expect the engine to take before it goes bang?
Thanks.
Ive driven a couple of TDIs, tweaked, standard, etc, and theyve all been really slow and felt rubbish, but since Ill never get 25mpg from the V8, I suppose its best to look at other options.
So - Im thinking a VNT, a larger intercooler, and a dual port inlet manifold, with fuelling modifications to suit of course.
How much power can I expect the engine to take before it goes bang?
Thanks.
hidetheelephants said:
I suspect 150 is about as much as you're going to get without grenading and at that level a careful eye on the EGT would be needed when using the power.
That should be adequate if I kept the weight down, I dont intend on having a roofrack or a rooftop tent etc, but I do occasionally tow, and I guess towing up a big long hilly A-road at 50mph is really when the EGTs would climb.Generally, whats the accepted EGT for these? I guess theres a "It should sit at X most of the time" and an "So long as it doesnt peak at more than Y" figure?
It's a bit of a "how long is a piece of string?" problem, depending on exhaust valve material, position of the EGT thermocouple etc., for longevity I'd fit an EGT and establish what the temperature is with a standard set up towing a full load, for example up a long climb where you can put your foot down and not gain speed much, then apply the tuning measures and avoid exceeding that temperature. Simplifying the issue the increased fuelling increases EGT, lowering intake air temperature with the bigger intercooler reduces it, I'd expect people offering diesel tuning to offer a balanced package that doesn't need an EGT but I'm an engineer and perversely like staring at gauges. Were you planning on using a specialist or doing a homebrew?
hidetheelephants said:
It's a bit of a "how long is a piece of string?" problem, depending on exhaust valve material, position of the EGT thermocouple etc., for longevity I'd fit an EGT and establish what the temperature is with a standard set up towing a full load, for example up a long climb where you can put your foot down and not gain speed much, then apply the tuning measures and avoid exceeding that temperature. Simplifying the issue the increased fuelling increases EGT, lowering intake air temperature with the bigger intercooler reduces it, I'd expect people offering diesel tuning to offer a balanced package that doesn't need an EGT but I'm an engineer and perversely like staring at gauges. Were you planning on using a specialist or doing a homebrew?
Definately DIY, if I paid a specialist to do it for me, A.) I wouldnt learn anything and B.) I may as well pay for the fuel my V8 drinks...Regarding valve materials etc, theyll all be standard. Opening up the engine and making major changes isnt something Ive done before, although if I was to do it, I guess a 300tdi isnt a bad place to start.
And yep, Im studying engineering too currently, and have always been keen on cars, all very interesting stuff. So the way to go about it is, make sure the engine is standard and in good condition before installing the EGT sensor/gauge etc, no blocked intercooler, no fiddled boost or fuel pump, cooling system working well with the right coolant ratio, standard bumper with nothing blocking the radiator etc, then load up the thing up as much as possible within the specified limits, find the longest, steepest hill on the hottest day in June, and drive up it flat out in 3rd or 4th gear several times and see how high I can make the EGTs go? Then make sure that whatever changes I make, it never exceeds that temperature? And that generally lower=better for EGTs, so long as its not smokey (thus running too rich), just when driving around normally?
Thanks!
In standard tune it tows nicely but you just need to remember the TDi isn't built for speed. Don't forget that most engines are now going to be 30yrs old too.
IMO most of the problems people experience with poor performance is often down to poor maintenance:
Fuel pump 'Boost' mechanism seized.
Delaminating and collapsed hoses.
Gummed up intercooler.
Valve clearances.
Etc...
If you want more power, fit a bigger engine.
M
IMO most of the problems people experience with poor performance is often down to poor maintenance:
Fuel pump 'Boost' mechanism seized.
Delaminating and collapsed hoses.
Gummed up intercooler.
Valve clearances.
Etc...
If you want more power, fit a bigger engine.
M
camel_landy said:
In standard tune it tows nicely but you just need to remember the TDi isn't built for speed. Don't forget that most engines are now going to be 30yrs old too.
IMO most of the problems people experience with poor performance is often down to poor maintenance:
Fuel pump 'Boost' mechanism seized.
Delaminating and collapsed hoses.
Gummed up intercooler.
Valve clearances.
Etc...
If you want more power, fit a bigger engine.
M
Yeah, Ive driven a few of them, all standard turbo, some tweaked, some not, all hopelessly slow. Im hoping for V8-ish performance, I want to be able to tow something heavy up a steep hill at 50mph. If the 300tdi just isnt up to it, then I suppose thats fine, Ill look for something else. Its such a shame we never got the 2.8 here...IMO most of the problems people experience with poor performance is often down to poor maintenance:
Fuel pump 'Boost' mechanism seized.
Delaminating and collapsed hoses.
Gummed up intercooler.
Valve clearances.
Etc...
If you want more power, fit a bigger engine.
M
LotsOfLaughs said:
Yeah, Ive driven a few of them, all standard turbo, some tweaked, some not, all hopelessly slow. Im hoping for V8-ish performance, I want to be able to tow something heavy up a steep hill at 50mph. If the 300tdi just isnt up to it, then I suppose thats fine, Ill look for something else. Its such a shame we never got the 2.8 here...
A healthy TDi should do 50mph but you might have to drop to 4th....but if you want V8 performance, you're gonna have to use a V8.
M
100SRV said:
VNT seems the easiest way to spread the torque curve.
No replacement for displacement.
Yep, and a 2.5L engine with a bar of boost has more displacement than a 3.9L V8, theoretically.No replacement for displacement.
It seems that the 300tdi head is absolute rubbish when it comes flow, I cant think of why else it makes so little power, compared to other 2.5L 4-pot diesel 4x4s and pickups
LotsOfLaughs said:
Yep, and a 2.5L engine with a bar of boost has more displacement than a 3.9L V8, theoretically.
It seems that the 300tdi head is absolute rubbish when it comes flow, I cant think of why else it makes so little power, compared to other 2.5L 4-pot diesel 4x4s and pickups
Maybe Land Rover didn't extract the most from the engine because they were concerned that the two-pinion differentials and monkey metal half shafts wouldn't cope.It seems that the 300tdi head is absolute rubbish when it comes flow, I cant think of why else it makes so little power, compared to other 2.5L 4-pot diesel 4x4s and pickups
100SRV said:
Maybe Land Rover didn't extract the most from the engine because they were concerned that the two-pinion differentials and monkey metal half shafts wouldn't cope.
Well you say that, but the TD5 and puma engines make a lot more grunt, so does the V8 actually. The R380 gearbox, as the name suggests, is built to handle 380nm of torque, and at 4000rpm, thats about 160hp, I think. Presumably its a bad idea to fiddle with the governor and make it rev more?100SRV said:
Maybe Land Rover didn't extract the most from the engine because they were concerned that the two-pinion differentials and monkey metal half shafts wouldn't cope.
Diesel technology has come along massively in the years since (remember the 200TDi is 35yrs old and even that was based around the previous TurboD). I suspect it's a case of they didn't have the tech back in those days, for it to be affordable and reliable.Then there's also the question of it needing to run on very poor grades of fuel.
M
LotsOfLaughs said:
100SRV said:
Maybe Land Rover didn't extract the most from the engine because they were concerned that the two-pinion differentials and monkey metal half shafts wouldn't cope.
Well you say that, but the TD5 and puma engines make a lot more grunt, so does the V8 actually. The R380 gearbox, as the name suggests, is built to handle 380nm of torque, and at 4000rpm, thats about 160hp, I think. Presumably its a bad idea to fiddle with the governor and make it rev more?300TDi would definitely benefit from a wider torque spread though, my 110 CSW is only just adequately powered when empty.
I've fitted an Allisport intercooler, increased the boost a touch to 0.95 Bar and rotated the boost compensator pin.
It really needs a VNT as the next step.
Gassing Station | Land Rover | Top of Page | What's New | My Stuff