|2/19/01: Over the past few weeks I have been revising the shop so that I could better proceed with the project. I finally installed the mondo air compressor I bought at an auction last year, with plumbing to the shop and the garage. It will store air to 175psi which will be good for tests on the air injection systems I’m fiddling with. I also horse-traded my way into a nice, small but very useful milling machine. With this, last weekend, I created the MK 2 version of the plate under the carb where air is routed into the cross-drilled throttle shafts in the AFB carb to make it “boost-worthy”. This plate also acts to thermally isolate the carb, straighten air, increase plenum size(maybe this isn’t a good thing….)and serve as the mount for the water/alcohol injectors. These are counter-sunk into the bottom of the plate, mounted to spray at a 45 degree angle into the plenum directly below the carbs. I am keeping track of the orifice size of the little welding tip jets which I screwed (and lock-tighted) into place. I used a “0.8” on one side and a “0.6” on the other side. I debated where to aim and where to place the jets, but decided to split the difference and just shoot for the center. At this point, I am about ready to bolt the whole shebang back together and start to sort out the new problems I have created when I removed the old problems…..|
2/25/01: Wirbelrohr- Well, in an old Dick Datson publication, he mentioned in passing the Vortex tube. I had heard about this device in Popular Mechanics as a kid. In that article, the device was being used to possibly HEAT the cockpits of jet fighters using compressed air rammed into a tube on the front of the plane, but the more common use has been to cool air. In industry, these are used to cool machine tool cutting bits without solvent for years. When operating correctly, the device makes a whirring sound and is sometimes called a Wirbelrohr, though I would rather come up with a French name for it…… The story of how these came about is fascinating and can be found in a thin little book published by Scientific American in November of 1958 called the the AMATEUR SCIENTIST by C.L. Stong “The Hilsch Vortex Tube” pp514-519. I was able to find it in local college’s library. Seems this French scientist named Ranque was experimenting before WWII and came upon the principle of air temp modulation. When the Germans came thru, they systematically scoured for new technology, and discovered Ranque’s work. Hilsch was the scientist charged with the duty of developing the work for the Nazi war effort. A scholarly, but very interesting note on it is found at: http://www.amasci.com/wirbel.html
I managed to build one of these things and have quietly been experimenting with it for about 12 months. The question is where to best use it. I’m sure it can be made more efficient, but at this point it does use a fair amount of compressed air to operate . It might be used just to cool a piece of metal somewhere in the turbo housing, to process air injected in to “power-up” the turbo preventing lag, or as part of an intercooling device. I have plumbed in the device as part of the air injector at the turbo compressor blades (see 1/8/2001). The injector does spin up the blades effectively on command (on the extra turbo) using about 75psi. This seems to work better than when I tried to spin up the exhaust side turbine blades. I’m thinking that the maintained psi will need to be higher than what the turbo alone will be able to store, and an air conditioning compressor will be necessary to provide blasts of cold air which I am after. See the links for on board air compressors I have provided. These compressors will not necessarily be running (robbing power) when I am hot-footing it. I’ll use the electric clutch they have with a relay to disengage when the Hobbs switch (see above) flips on. Or, it may be that I will be able to keep “ahead of the game” if I augment the tank pressure with periodic stops at the gas station tire pump. We’ll see……
2/26/01: Spent the day putting the manifold/turbo/carb back on the engine. It looks like everything will fit, though I’ll need to make a few changes to get the regulator where I want it, and the throttle linkage now needs more radical revision. A 53′ Champ air-cleaner will nestle in over the turbo with dual stock filters looking very much at home. This will be attached by rubber tube to the stock 90 degree elbow fitting from the inlet of the turbo (cleaned up and with some holes plugged it looks really right….). The waste gate pivot attached perfectly to the cannister/adjustable arm assembly. There is enough room up front for the tubing I’ll need for the adjustable plenum, and there was enough room by the pitman arm for the adjustable runner. I was able to find the cause of the oil leak at the front of the block (a thru-bolt was missing which went into the crankcase just above the oil pan). The profile still puts things above the “hood line”, so for now I remain a hoodless hoodlum….. I read in an old turbo book that the 67′ Pontiac had a combination vacuum/pressure control on the distributor which could be used to retard ignition on boost (about one degree per pound boost). It is Filco #VC189X. Also, late 70’s Fords had vacuum controls made for the smog vehicles which apparently could advance and retard (two nipples). I will try to find one and adapt it to my distributor.
Home page Next chapter