A few years back I made a good gain in performance by relieving excess pressure in the exhaust manifold of a C.T.20 turbine on a 2lt engine by enlarging the wastegate and modifying the entrance leading up to the wastegate. Dougal thinks that it's impossible. I think it has to do with the flow of exhaust gas at high speeds, once the required boost level is reached then any excess pressure in the manifold is supposed to go out the wastegate, however gas travelling at high speed has a lot of inertia and wants to go in a straight line rather than take a sharp turn into the wastegate port. If the entrance to the wastegate is changed to allow some of that gas to exit instead of damming up in the turbine then there should be a gain in airflow across the engine.
turbo vs supercharger for 2B diesel, lots of mud and crossing creeks
- Thread starter Tin Tin
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A few years back I made a good gain in performance by relieving excess pressure in the exhaust manifold of a C.T.20 turbine on a 2lt engine by enlarging the wastegate and modifying the entrance leading up to the wastegate. Dougal thinks that it's impossible. I think it has to do with the flow of exhaust gas at high speeds, once the required boost level is reached then any excess pressure in the manifold is supposed to go out the wastegate, however gas travelling at high speed has a lot of inertia and wants to go in a straight line rather than take a sharp turn into the wastegate port. If the entrance to the wastegate is changed to allow some of that gas to exit instead of damming up in the turbine then there should be a gain in airflow across the engine.
They're the numbers on the entrance to the turbines, the other numbers are 15H and 15R.....
The 15 is the one you want.
A/R of 15cm = 0.59 inches.
Find a housing for the same turbo with a smaller A/R (like 11cm) and you'll get boost almost 30% sooner.
Damn! I've got 2 of these and can't use them!
Kalgoorlie- Capitol of New Zealand
Capital of Aus Zealand.
But the family I have are in Perth somewhere. I flew through there once for work at a small town further south. Spent 11 hours in the Perth airport terminal befor they had internet there.
Never actually got into down-town Perth.
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Seen one city-seen em all.
I justed posted some pics of turbo diesel power - just for Blownoiler. See my new post "1HD-FTE POWER"
You will notice foot to the floor without much smoke (cant see any thats significant). 24psi boost. And super practical. 750nm at 2000rpm, better than 600 at 1600rpm (cant actually test it at the moment). Not much lag, not much smoke.
So while your not in Perth to test drive, you can get a feel for it in the pics
You will notice foot to the floor without much smoke (cant see any thats significant). 24psi boost. And super practical. 750nm at 2000rpm, better than 600 at 1600rpm (cant actually test it at the moment). Not much lag, not much smoke.
So while your not in Perth to test drive, you can get a feel for it in the pics
If super chargers and diesels don't work together, then somebody better tell Gale Banks he's doin it all wrong?
Been covered, go back and read it.
I think that the real issue is application, each form of charging (crank driven versus exhaust driven) both have their good and bad points.
Having driven a rootes charged diesel in a higher mileage application (daily driver) (800-1000 kilometres per week) I realized that the noise levels of the old design blower were too high for my liking, I'm a bit older than a lot of you guys, and that old saying fits- "If it's too loud then your too old" .....well I must be too old because it's too loud, but then so are a lot of aftermarket exhaust systems in my opinion! (They weren't too loud when I was younger, they sounded "cool")
I'm not going to talk about how ones nervous system becomes more sensitized to loud noise with age here....oops I just did
, but noise is just one of the issues, if the car only got used on weekends then the noise level would be o.k. for most folk (as would a more expensive,quieter screw compressor). Other criteria would be initial cost, ease of fitment, legality, emission considerations,fuel usage, spares availability in your area ,drivability etc.. , I haven't even touched on performance here, because each application is unique so it's going to be difficult to do any comparisons between the two (or should I say 3- the crank driven turbine adds yet another complication). Gale Banks's build (among others) gives us a big hint as to wether superchargers and diesels work well together, it's a shame he didn't post some dyno graphs with the engine advertised, there isn't enough information on the net about these builds, but I think that we are going to see more in the near future! 
