What to expect?

[dr_airtime]

The 2.5" Exhaust is definitely the best mod out there for L300's. Got my side-dump 2.5" done at Hoegler's in Richmond like most on Delica.ca.

2.5" drops RPMs by 300-400 on highway. Also this helps hugely with climbing as the Deli has more power (torque) before a shift into overdrive that occurs earlier with a stock muffler. Pretty much a must-do Mod if a lot of your driving is around North Van on and Sea-to-Sky.

I'm going on two years of second hand ownership using 200:1 two-stroke oil with every fill up and still on original IP and deli running great (175k and original IP with likely never any tune). I've done three semi-annual seafoams removing the fuel filter intake/outake hoses and going directly into IP but didn't notice a difference on last two seafoams so going to reduce this to annually. I think the Sea to Sky hills makes sure the heat is there to clean out the carbon deposits compared to driving in a lot of other places because of short sprints.

I don't have an EGT guage but try not to run above 3500 rpm for more than two minutes at a time on Sea-to-Sky. I wouldn't try going above 3000 rpm on Coq or Duffey though without an EGT.

[FalcoColumbarius]

• My two bits:

I've got a two and an half inch SS pipe (w/mandrel bends) but I can't see how that would effect the kick down linkage for the transmission, which governs which gear you're in, ergo the RPM. The stock pipe on the Starwagon is one and a quarter (or so) inch diameter, adding the two and an half pipe does help cool the exhaust temperature a little and as Bionic noted ~ sounds way cool (also looks cool) but the trade off is a little less back pressure, which helps push the turbo. You got to remember that heat is power to a diesel engine and although too much heat can break your head, not enough heat and your engine performance sucks.

My experience with the EGR valve is as follows: I got into an argument with friend of mine about the EGR valve. His view was that they serve no real purpose and should be removed. In the meantime my wagon was working fine and I had an EGR valve, so my argument was "after 150 years of being in business, wouldn't Mr. Mitsubishi know what he was doing by now and why would he put this thing in the motor if it served no real purpose?" His response was that it wasn't Mr. Mitsubishi's call, it was some bureaucrat in the Japanese government that knew better than everyone else. The idea behind the EGR as I understand it is to reduce nitrogen oxide emissions from the engine's exhaust, which are the result of the heat of the combustion and believed to affect the ozone layer in a negative fashion. By reintroducing inert gasses that have just been processed by the engine, the combustion is thought to be cooler because of the use of less combustible oxygen in the process. So one day I pulled my EGR valve out and took it apart for inspection. What I found was what appeared to be glazing putty pushed into the aperture of the valve. What I did was clean the mess out, put it all back together and drove off. Well, my mileage went from eight point five kliks per litre to six; I experienced a loss of power; my engine was running very hot and I was dumping clouds of soot out my tail pipe. I was livid. So I installed a mild steel blanking plate. My mileage went back up to eight point five (30% increase); power resumed; engine ran cooler; no more soot out the tail pipe.

Then I discovered galvanic corrosion. It turns out that steel and aluminium, especially under heat, tend to argue and steel wins. I was driving out of Kamloops, up that big hill that goes to Merritt, when I suddenly felt a dramatic loss in power. In my researches I went to undo the two bolts that hold the EGR valve to the intake (where I installed the mild steel blanking plate) and to my surprise they both pulled out with my fingers. On closer inspection I noticed little springs wrapping around both bolts. Then I realised that these springs were in fact the threads from the females that the bolts screw into. Perhaps I may have tightened them too hard but I'm sure that the mild steel plate had something to do with it. In the end I spent an hundred bucks and had quarter inch aluminium plate seal welded to the intake and a losange shaped steel plate for the exhaust manifold end, though I had to make a gasket that would stand up to the heat so I purchased some brass shim material, so far so good.

I was considering turning the turbo boost up until it was explained to me by a few mechanic friends that there is an optimum collection rate that the compressor works at and that the sweet spot is between eight and nine PSI and if you turn it up over nine PSI it of course spins faster but collects less air, therefore pushing less oxygen into the chamber. This is why there are twin turbos on the market. There is a design of turbo on the market that intrigues me: The twin scroll turbocharger.


"Twin-scroll or divided turbochargers have two exhaust gas inlets and two nozzles, a smaller sharper angled one for quick response and a larger less angled one for peak performance.
With high-performance camshaft timing, exhaust valves in different cylinders can open at the same time, overlapping at the end of the power stroke in one cylinder and the end of exhaust stroke in another. In twin-scroll designs, the exhaust manifold physically separates the channels for cylinders that can interfere with each other, so that the pulsating exhaust gasses flow through separate spirals (scrolls). With common firing order 1-3-4-2, two scrolls of unequal length pair cylinders 1-4 and 3-2. This lets the engine efficiently use exhaust scavenging techniques, which decreases exhaust gas temperatures and NOx emissions, improves turbine efficiency, and reduces turbo lag evident at low engine speeds." (Wikipedia)

I'm more interested in the reduction of turbo lag than I am in the EGR aspects but it looks interesting.

When it comes down to it one must remember that we are talking about the 4D56T 2.5 litre engine, not a V12. It's a diesel and has to be driven as a diesel. If you "drive it like you stole it" you are likely going to blow the head.

If you adjust the fuel on your injector pump, remember that: 1/ A quarter turn is too much, you're turning in small increments, degrees; 2/ too rich and it gets hotter but bear in mind that if is too lean then you have too much air and it will still be too hot. There's a sweet spot.

Pyrometer? Cockpit ambiance.

Would I race a Ferrari F40? Certainly, so long as I got to pick the track. Think: Tortoise and the hare.

Falco.