Been extremely busy with my day job and other pressing realities, but have now found a bit of time to continue on with the project.
A recap of the "turbocharger" situation. There were recent comments elsewhere about using a more modern turbo, , efi, etc. While that is all well and good, I am going to use what I have planned to use all along - old technology - because that is what I have on hand, and I acknowledge the shortcomings. It is simple, has been proven, and most importantly, I have actual experience with it (don't underestimate the value of hands-on experience) and doesn't require complicated fabbing for which I have no $$$ or equipment. So there.
I eventually would like to go with some variant of efi, but that is down the road, and not now. I also eagerly watch the progress of Robert k., who's project is moving along as well. Unfortunately, we seem to be the only two who are actively doing something along these lines. Unless there are others I'm not aware of.
If you go back to some of my earlier posts, my calculations indicate the original 152t turbo (a trw b flow) is wholly inadequate for the flow requirements of a 196 turning maybe 4,500 rpm - max - and 7 lbs. Boost. An f flow, found on the later corvairs, is better, but marginal. In fact, too marginal for my comfort level. I have the f flow components, however. There was another possibility here, though. The trw turbo was sold off to rayjay, who upgraded it with an e flow variant for engines 200 - 300 c.I. So my plan is to put together a trw/rayjay turbo that has an e flow compressor, coupled with an f flow turbine. Here's the rationale for this: a trick used successfully (I did this, in fact) with the corvair setup was to marry a late f flow cold side with the early b flow hot side - this gives quicker spooling and greater boost and flow, to a point. In effect, I am going to prove this trick works with a 196. Since these engines turn so slow, the rayjay e flow would likely have late boost. In this way I
believe I can bring boost on around 2,800 - 3,000 rpm, by using an f turbine, which is smaller than an e turbine, which would meet my needs. That's my premise, and with my gearing of 3.73:1, I'm hopeful it will pan out.
Towards this end. A few days ago I sent off the stock IH trw "b" flow turbocharger compressor housing to be machined to accept an "e" flow compressor wheel. It should be back in a week or so, but there will not be time (vacation) for me to assemble it before, say, late August.
Today I performed another modification to the disassembled turbo. In the original 152t installation, oil is supplied to the turbo with a fitting that enters the center section, at about the 11 o'clock position. Due to the fittings, I am a bit nervous that I May not have underhood clearance for this. So I drilled a new oil feed, which will allow oil to enter the center section at about the 5 o'clock position. How can I do this? Easy. The IH turbo is the generic trw b flow, whose center section was cast with three webs supporting the bearing support (web every 120 degrees, interspaced with a drain boss every 120 degrees as well). Any of these can/were drilled according to application needs. So I chucked it into my drill press and did a pretty good job of lining it up and drilling it through. The old passage will be plugged with a 1/8" pipe plug. I broke through a little off center, but I have an extra center housing here where the factory machinist did little better.
with the corvair turbo, GM spec'd only one supporting web, and a drain in a particular orientation, which met their need, but limits its use for other operational needs. That's why these turbos don't readily lend themselves for fodder as an option to the 152t unit.
I had put a bunch of numbers into those "effective" compression calculators and came up okay. Please explain what's going on here.
