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Hi All
Just wanting to know what can be done to a 2004 4.2 turbo engine to increase power & economy
I know i don't ask for much,
The 3.0lt common rail seems to do ok with a computer upgrade & exhaust!
I assume a 3 inch mandrel bent exhaust will be the first step, I know boosting the Turbo creates power but where do you stop, The vehicle will do the canning stock route one day so it needs to remain reliable
Any suggestions would be fanastic
i put a 3" mandrel bent on my TD42 as well as a few more PSI boost and made a heap of difference to power and better economy..
Thanks for your reply
Do you know how much it was increased by & How?
Regards Glenn
Standard boost is around 7-9Psi, increasing it to its safe maximum of 14Psi is as easy as fitting (and adjusting) a boost bleed valve which costs around $100. Increasing boost on it's own won't give a significant increase in power but it will lower your exhaust gas temperatures which is good for diesels. To get the full benefit from incresed boost the fuel system needs to be tuned to suit, this is something best left to the professionals because if you don't know what you are doing and get it wrong you could do some serious engine damage.
My suggestion would be to fit a 3" mandrel bent exhaust system including dump pipe, and fit boost and pyro gauges at the same time so you can keep an eye on the engine.
After that talk to a few diesel tuners about which chip they recommend and discuss increasing boost for more power.
Tony
swap you my tb42 :-)
Thanks Tony. Sounds like it is relatively easy to pull more power,
Do you know what sort of gain in power & torque to expect with this sort of mod?
The easiest things to do are exhaust and tune with higher boost.
Then the $$$ starts to pile up, the factory intercooler, airbox and turbo are really only good for around 15psi. A new turbo and intercooler running 19-20psi will give you around 140 kw at the wheels (safely) but will cost you around the 4k mark, much better than the 60-70 they come from the factory!
If more power is wanted, the injector pump will then need to be modified costing mega bucks
There are no chips avail for the td42, they dont have efi so it is just not possible. The td42ti models do have an ecu but all it does alter injector timing and may even control the egr valve, but fuelling is still done by the mechanical injector pump. You can prove this by disconnecting the ecu, the engine will still start & run.
I had local workshop put a 3' exhaust, upped boost and increased fuel supply on my GU1V ute. Max power up to 155hp (US dyno) at wheels and unbelievable improvement on driveability and over taking.
Fuel economy virtually unchanged after I got over boy racer with new toy syndrome. Boost gauge shows about 5 lb boost at 100kph and exhaust temp 300 although goes up to 15 lb and 450/ 500 quickly when under load but drops just as quickly when you back off. Most impressed.
GUte,
So if the ECU controls the injection timing on the TD42Ti couldn't you just lengthen the injection time to get more fuel in, like in petrol motors?
Thanks Flex
Welcome to the forum Flex.
It's always nice to post an introduction before asking questions.
The factory ECU (like all factory ECU's petrol or diesel) is not adjustable so you can't just 'adjust' it to add more fuel.
Also, injection timing refers to the start of injection, not injector duration or fuel quantity injected.
Tony
Tony,
Sorry, just introduced myself: Here
I'm a bit confused now on the comments that "GUte" said about un-plugging the ECU and the motor could still run. If the ECU controls the start of injection timing, without you would never get a "start" of the injection cycle i.e. no fuel.
Thanks for the intro.Quote:
Originally Posted by Flex
While the engine may (I didn't think they would but if he's tried it?) start with the ECU disconnected the injection timing would be a default base setting.
I need to do a bit more research because I thought TD42Ti also had fly-by-wire throttle control.
Tony
Tony, I check the wiring diagram I couldn't see any evidence of drive-by-wire. So the only way to increase the power on the TD42Ti is to modify the pump?
You will get some increase from a chip as it alters the timing like ignition timing on a petrol.
Modifying the pump may not be necessary depending on how much more power you want. If you keep the standard turbo but up the boost to 14Psi you can usually get enough fuel from the standard injector pump. Start fitting bigger turbo's and intercoolers and you will probably need to have a bigger plunger fitted to the injector pump to be able to supply enough fuel.
Tony
Would you still need to tune the pump if you change the injection timing? Because there is no electronic control of the governor?
To change the injection timing would require tuning and computer adjustment. To adjust fuel flow (which you do to compensate for more boost) is a manual adjustment but one that is better done on a dyno by someone who knows what they are doing.
Tony
(hope I dont sound rude, not my intention)
What computer adjustment are you talking about YNOT? The only thing the computer does is a 'trim' of the timing control valve according to inputs from the throttle (tps) and needle lift sensor in number 1. A chip is not an option for the TD42Ti as the computer only controls ancillaries and not injection timings or quantities. Timing has to be adjusted manually, by physically rotating the injector pump and using dial indicator and adapters (cheap off evilbay) also the boost compensator diaphragm gets rotated to give the fastest off boost response to get the fuel into the engine to spool the turbo up. As YNOT has said though better done on a dyno and shouldnt be attemted without boost and pyro gauges.
Regards
Dave
I'm not overly familiar with the TD42Ti control system. My understanding and correct me if I'm wrong, is the computer trims the injection timing much the same as a petrol EFI computer can trim the ignition timing. Base timing is still set by rotating the pump housing.
Any information you can add about the TD42Ti control system is apprecieated.
Tony
Yeah YNOT that is pretty much on the money. It is a very basic form of emissions control. everything else works the same as a TD42T fuel system, it just has a trim, it adjusts stuff all really and can be uplugged (as well as tps and needle lift sensor and will still run fine. With the TD42Ti, the timing cant be adjusted much over .68 (I think) as it has a bit of a hissy fit. To get the best out of it though leave it all hooked up.
Do you have a list of pump timing settings for TD42 and TD42T, factory or what you have found works best?Quote:
Originally Posted by Bucky
I have a Nissan Y61 training manual that gives the spec for a TD42 (naturally aspirated) at 0.62.
While we're on the subject, do you have a timing setting for TD27T?
Tony
for a TD42T .72 - .78 and over depending on setup. can run alot more than that on a modded pump and turbo. TD42Ti .68-.70 this is a bit touch and go and should be done on a dyno or by someone who knows their stuff. sorry cant really help with the NA stuff, havent done much with them. I barely ever touch the max fuel screw, most of the tuning is done on the boost compensator and timing and boost. then you can maybe give a little max fuel.
(this is general advise and should be done in conjunction with pryo boost and afr readouts on a dyno)
OH they arent factory either. Ive found some TD42T\i pumps with timing as low as .57
That's interesting that you don't need to do much with the max fuel screw, I'd like to know more about the timing (I know how to adjust the timing and have the tools to do it) and boost compensator adjustments but that's for another time and place and for my own curiosity.Quote:
Originally Posted by Bucky
Tony
With regards to the max fuel screw, its all dependant on your egts. If after doing the timing, boost compensator and winding the boost up abit (im talking stock turbo) u find u have high or low egts u then can adjust max fuel to get your highest egt around that 550 degrees post turbo. we then get into one of the biggest issues with the stock setup, which is the highly restrictive inlet path from out.of the turbo all the way to the manifold. The best thing to do is to manufacture a 2in bolt on outlet for the turbo, then make up a 2in pipe to replace the stupid pipes that are stock. Some good gains are there to be had by small mods. The faster and easier you can get the air in and out of the turbo (compressor and turbine) the better. The better it all breathes, the lower your egts will be, the more fuel and air.u can get in therefore making better useable power.
I have a 2000 TD42 that devolpes almost no power untill it reaches about 2000rpm, I have done the following, 3" exhaust with 72mm? dump, EGT & boost gauge, Fitted factory nissan intercooler, Turbo hi-flowed by MTQ, I also played with the fuel screw and boost compensator by taking one of the shims out and rotating the plunger several directions but these made no difference, could my pump need a rebuild? I noticed the plunger had some "chips" in the chrome on it.
It starts very easy and runs smooth, although at about 1500rpm when cold it flutters a bit after it warms up no probs.
At 18psi and EGT of 520 deg it is producing 95kw at the wheels but still nothing down low, what should I try next and what order?
My thoughts were: Valve clearances, Injectors, Inj Pump rebuild (costly), Inj Pump upgrade with 12mm plunger ( more costly ), Inj pump timing?
Any help regards Dave
This is the power I got out of mine With standard pump and turbo.. Done on a dyno
http://www.nissanpatrol.com.au/forum...539#post211539
So the torque figure you said you had, almost 700.. that's in NM's? I just find that hard to believe!Quote:
Originally Posted by Lewy
With regards to the ilovebeer i would be getting in on a dyno the pump needs to be adjusted correctly from your compensator so it can get fuel in there a lot earlier with a good tune you should be able to get peak torque figures by 2000rpm.
As for the torque figure in lewys dyno its tractive effort theres no easy way to convert this to nm/ftlb etc that i have found yet.