Limited disassembly of a 1980 IC 196

Hooked up the a/f gauge and went for a drive. Idle a/f is around 16.5:1. This is a hilly area so the following numbers vary but in general when I'm at 9" hg, I'm at 13:1, level cruise 14 or so (varies a lot), but when I hit boost I'm immediately down to 12.5 or so, heavier throttle 11.9. I again pulled 7 lbs. On a short, but steady grade and it held at 11.9-12.3.

On my favorite grade (driver's flat) I'm pulling an easy 60 at the top of the grade in 4th, 6 lbs. Boost. Before it was 3rd gear, floored, 45-50 mph.

This thing is still Rich, in my estimation. I'm going to try the original rod/jet combo. What's in there now is a modern duplication of "original" jetting but a +1 rod (Rich).

Got the choke set right. Starts right up and warms up fast.
 
While you are fat, you are cool and safe. Not a bad place to be.
Thought you said you had no power enrichment system? Looks like you do.
 
Brain fart/misunderstanding. There obviously is an enrichment mode, it just isn't a pintle-valve thing like in a Holley (think 1904 or 2210).
 
Just got done getting new aluminum rims and cooper discoverer atp tires for it, which involved my first drive down to Auburn. The old tires on it were made in 1998 and unsafe (duh). Now I have a smoother, and quieter ride, but the tire's quietness lets one hear all the other rattles and rumbles masked by the old knobby's road noise, and missing weatherstripping, bare floors, etc.

I pushed it a little more. I think my boost maxes out at 7 lbs.; which is okay by me. It gives decent performance going up the grades around here. We'll see what it does when I actually drive it up to tahoe one day.

Still working out some bugs. The exhaust system is terrible. It vibrates and rubs against who knows what, probably the underside of the bell housing. I have an nos right side tail pipe and can route it smoothly straight back along the passenger's side. That's probably a spring project at this point.

Another thing I plan on doing is based on Robert's comment about closing off the coolant to the exchanger in winter due to a much slower warm-up. I've sourced the heater shut-off valve for the '80s GM products; runs on vacuum. Cost is $14. However, vacuum shuts it off and the tvs needed is backwards from anything I've seen on IH iron. A light came on. My 1985 jimmy has a vacuum operated exhaust heat riser valve. In a cold start, it receives vacuum and closes off; when coolant reaches 105 degrees, the tvs that supplies the vacuum shuts off the vacuum and the heat riser opens. This is backwards from the tvs the Scout uses to prevent vacuum to the egr until the engine warms up. So I need a trip to picnpull to find a tvs on an appropriate GM product. The shut off valve will be shut off, preventing flow through the exchanger, until coolant is over 100 degrees, and then the flow will resume. By then the oil will have warmed to some degree.
 
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Regarding the previous post, I've located an efe ported vacuum switch for the application that shuts off vacuum at 130-140 degrees. That's even better.

Robert,
quick question: what a/f ratio would begin to make you nervous? Anything over 13:1?

I'm trying to listen for ping but don't hear it at this point. I say trying because this thing is like being in a drafty can. Let's say I don't have any, I.e., I'm running Rich enough. Then in theory I could pull a long grade floored, say, 7 lbs. Max boost if that's what it is capable of, and just keep going as long as the oil temps stay in check? The reason I ask such a simple question is that I still find the idea novel that this engine could actually run that way and not blow up. Didn't you say that properly done, of course, that these engines were quite capable of handling at least 10 lbs. Boost? I'm envisioning if I drive this thing to socal and pulling the grapevine outside of bakersfield. Several miles going from whatever bakersfield is to the top of tejon pass (4,200 feet), probably in boost mode.

I'm going to see if I can somehow post a pic of a section of data logging. Right now, I need to hook up the laptop and see exactly when my boost is coming on. In a hilly area, in 3rd, boost is almost immediate at any loading, so the turbo is already spooling. Haven't gotten any in 1st, yet...it's also late in 2nd.
 
Mark pietz said:
regarding the previous post, I've located an efe ported vacuum switch for the application that shuts off vacuum at 130-140 degrees. That's even better.

Robert,
quick question: what a/f ratio would begin to make you nervous? anything over 13:1? Assume at max map, then
12- 12.5.
I'm trying to listen for ping but don't hear it at this point. I say trying because this thing is like being in a drafty can. Let's say I don't have any, I.e., I'm running Rich enough. Then in theory I could pull a long grade floored, say, 7 lbs. Max boost if that's what it is capable of, and just keep going as long as the oil temps stay in check? The reason I ask such a simple question is that I still find the idea novel that this engine could actually run that way and not blow up. Didn't you say that properly done, of course, that these engines were quite capable of handling at least 10 lbs. Boost? I'm envisioning if I drive this thing to socal and pulling the grapevine outside of bakersfield. Several miles going from whatever bakersfield is to the top of tejon pass (4,200 feet), probably in boost mode.

Mechanically they could take way more than 10#, the problem becomes thermal over time at load. Oil temps (you have that covered), hot spots in the head, spark plug temperature, valve temperatures. Be sure you ate running at least one heat range cooler on your plugs. Then go beat on it for a period of time so temperatures stabilize like 1-2 minutes at max torque/boost. Pull the plugs and look closely for signs of excessive heat. This is where you dial in your optimum afr and spark lead.
A astute observer can feel any loss in power like when it starts to lay down after a spell at high load.

I'm going to see if I can somehow post a pic of a section of data logging. Right now, I need to hook up the laptop and see exactly when my boost is coming on. In a hilly area, in 3rd, boost is almost immediate at any loading, so the turbo is already spooling. Haven't gotten any in 1st, yet...it's also late in 2nd.
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123
 
Robert kenney said:


123
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Thanks for the response. I feel a little like the dog that chased the car and then actually caught it. Now that this thing actually runs, I don't want any unforeseen surprises.

I'll change the plugs after the gv show this weekend. It looks like waaay more work than I want to do tomorrow.

The plan is to put some miles on it and drive up and down (or is that down and up?) the I-80 freeway to get a sense of turbo loading, etc. Down is towards sac - no load, cruise conditions. Up is towards colfax and beyond - climbing grades that culminate in tahoe, etc.

Regarding your comment about what gets hot and makes a mess of things. I feel pretty good about the oil heat exchanger; that's easily monitored. The other things are unknowables until something happens.

My thought is this: assuming the turbo is actually now a little undersized with the b flow turbine in that it comes on a little too early in 4th gear, notwithstanding boost limited to maybe 7 lbs., I would be willing to put the f flow turbine on it. This would delay turbo boost, which is really not a bad thing if I need to pull long grades. I had the f flow turbine on it when the e wheel stuck. I was getting boost on my "favorite" grade at the time. The point is more power at higher elevations. I don't want a choice between no boost and full boost. I believe the f flow compressor is just right.

But in going over - again - my after-action analysis and reconsidering mcinnis's material, I can see that the e wheel was way too big and May have hammered out the bearing due to surge, now that I have a much clearer understanding of what surge is. A compromised oil feed didn't help, either.

Is my logic somewhat sound?
 
Mark pietz said:
Is my logic somewhat sound?
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Yes I think so. I also think your expectations are sound..

Are you about 12.5-1? If so after you return from "Grass Valley days" , put aside a good day to tune what you have. You need to know what it sounds like if it pings. Ignition timing requirements should be very predictable. For 0 vacuum lets say 34 degrees mech. Advance, then pull 1.5-2.0 degrees/pound out above 2 pounds.

Frequent plug checks paying close attention to rounding of corners using a eye loupe. Color should still be visible say 1/2 way + up the insulator. Using new zinc plated champions only, on an already up to temp engine drive a little low speed to get color on the plugs then, make a good hard 30 second -1 min wot pass up your favorite hill. Pull over and look for heat on the ground strap around and down on to the threaded body. The zinc plating should stay basically untouched on the threaded end.

Its a hard process to translate with out being there.
 
Robert,
I really wish to thank you for sticking with this and being patient with me as I stumble through. I have so much to learn and there are so many little tricks to all this that I do not know. I also do not wish to blow things up because I was ignorant. I've done enough of that along the way. I hope others have also learned from this sojourn.

Last night I put some high temp rtv on the underside of the long stud on my adaptor. I knew I still had a tiny vacuum leak. Fired it up a little while ago and warmed it up and let it idle. Now ether has no effect on idle and my a/f gauge (wow, that's the 8th wonder of the world!) showed a noticeable decrease in ratio. I adjusted the idle mixture screw to around 14.5 - it actually responds and you can see the effect of any adjustment. Wow. How did we live without these things?

Okay. I'll go to the next colder plug and monitor things. I'll also be sensitive to swapping out the b flow to the f flow. I don't want to always be in boost because of any sort of load, gratifying as it May be. Boost is for when I really need it, not for whoooopie. Also, years ago I had purchased a pressure switch when I owned my corvair, with an eye towards water injection. I still think that would be desirable for, say, boost over 2 or 3 lbs. Just because. Would be easy enough to do.

Looking forward to Grass Valley.
 
Drove it up to gv and back. Engine runs smoothly, but the exhaust system rubs/vibrates/resonates, and as I flog it around with its new-found power, my brand new tires and rims reveal other suspension problems - I'm all over the road, needing shocks and possibly a steering box rebuild.

I got 16 mpg out of this tank of gas, this with my foot always in it.

Saw bill's efi setups on a number of rigs, and what they do for the four bangers is amazing. I can clearly see that I need to feed my beast with a modern fuel management system.
 
123 is 123.:icon_lol:
because I quoted your post and added red text within the quote bubble, I had to type at least 3 characters before I could post hence 123.
 
Robert kenney said:
123 is 123.:icon_lol:
because I quoted your post and added red text within the quote bubble, I had to type at least 3 characters before I could post hence 123.
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An easy first step in tuning this is that I removed the metering rod and carefully sanded the tapered end to reduce its diameter by 0.001" to increase flow; the diameter of the taper of the next richer rod is smaller by 0.002". I have the specs for these rods and its easily done by chucking into a drill and miking as I go along. A blast up my favorite grade shows I enriched things by 0.3-0.4, so I'm now in the mid to high 11s. Might go another 0.001". I don't wish to go richer across the board, just in the boost range, which is when the taper comes into play. Tomorrow I'm going to pull a plug to see exactly what it was I put in there. I also just discovered how to export the data from my dynolicious app for each of the runs. It saves to the photos on my iphone, then I hook up the phone via cable, to my computer to import. Then I can post it here. Have to do that tomorrow.

I do like how smoothly the turbo operates. I pump the pedal once to set the choke and it fires right up and the choke comes off after a few minutes. One thing I noticed is that 1st and 2nd gears are "shorter". The Holley 1-bbl has a 1 11/16" bore, and this carter has a 1 1/2" bore, so it runs out of breath in those gears sooner during a full-throttle blast. But when it goes into 3rd, the boost really comes on. Because my suspension is loose and crappy, I have trouble gauging its performance on my favorite grade which has an "ess" turn to it - I "outrun" the suspension and have to back off. Once I get the richness better dialed in when running up to 8 lbs., I'll go down to the interstate (I-80) where I can have straight line blasts and pay attention to shifting instead of one eye also on a gauge, which is distracting.
 
Here's a hastily taken pic of me going into boost. I've seen it go to 8 lbs.

Also is a pic of the dynolicious screen shot of one of my few runs with the turbo. You can see the shift points and that I dropped off when I hit 4th and didn't recover (I was keeping an eye on the boost gauge and also the a/f ratio gauge and was beginning to get sideways). This run was 87 hp (rear wheel). I'm still looking for a decent place to get a straight run, without distractions. I'm considering my baseline to be 70 hp, and am thinking that I will actually end up around 100 hp (rear wheel) or so once I get a better tune and a clean run.

I'm currently running champion rj12ycs. I see where I must have chosen to run a hotter plug than the book says, which is a rj10yc. I pulled #1 plug (easiest to get to) and its color is a nice light tan or brown. No blistering or anything unusual as far as I can see. But I'm going to switch to the rj10yc which was the stock plug. No reason I should go even colder, is there? At least for now? Plug access is now a lot more difficult.

IMG_1914_2.jpg

IMG_1939_2.jpg
 
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All of your data looks good. I would also leave the metering the way it is. 11.5 is really good and richer could take away from the energy to drive the turbine.

Another opinion from the peanut gallery. :ihih:
your stock Holley is 1-11/16. That is for the stock 196 air flow. @ 8 pounds you are flowing a minimum of 50% more air and fuel. I think you're woefully under carbureted even with the Holley. You stepped down to a 1-1/2 venturi?

Let's just look at some relative numbers and tell me what you think.

Stock 196 @ 3800 rpm and 75% ve can flow 161 cfm.
Add 50% (8#) you're now flowing 242 cfm. I bet you could see 10# with adequate carburation.

Looks like a small 2bbl Holley May be better. Boost will come quicker, turbine speed May drop due to being under more load and you'll have better afr adjustability.
32/36 dfev weber. 240 cfm, progressive 2 barrel. Has vacuum actuated power enrichment system. Easy enough to port manifold vacuum to the power system so you get it when you need it.
 
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I know I can flow a lot more if I were to put a bigger carb on it. Right now I don't know how much boost I can actually generate until I ensure I don't go lean and detonate (perhaps with my jetting mod I've settled that for now). I backed off at 8 lbs., and there was more. I'm also running a 2 1/4" muffler and tailpipe instead of the full 2 1/2" piping, so I'm squeezed down there a bit.

Going back to the original 152t setup. They were sucking air and fuel through that teeny Holley 1904. I'd guarantee that restriction was quite limiting for boost, although probably by design to keep them out of trouble. The corvair setup started with a carter yh with a slightly smaller bore and b flow, then they upgraded the carter to the 1 1/2" bore and f flow. That's essentially the setup I am running. Exhaust was a full 2 1/2" piping, as was the 152t. So it was choked at the front end.

I don't want to run this thing on the edge, although it would be cool to safely generate 10 lbs. If needed.

Right now I have other tuning things to focus on. Yesterday I pulled a plug and am running champion rj12ycs, which are one (two?) step hotter than the rj10ycs listed in the fsm tune up specs. I just came back empty handed from napa because they no longer show a rj10yc listed. What plug do you recommend in this case, since I should try the next step cooler plug. You said you run champions, so what do you have in mind? In pulling the easiest plug I pulled the wire out of the boot now have to fix that, and removing the big trapezoidal heat shield to access the plug itself was a chore. A lot of the corvair guys ran webers so much so that clark's corvair includes them in their catalogue with sizing recommendations. Something for me to keep in mind.

Edit: to document some data that just came to my attention, the trw b flow turbo flows 320 cfm @ 120,000 rpm (max); the f flow is 430 cfm, likewise. So I believe my instinct about combining the f compressor with the b turbine was spot-on. Early spooling with greater flow for an engine that turns relatively slowly. This is why my boost comes on relatively quickly. I got my datalogging feature working again and went for a couple of runs. I'll see if I can post a screen shot. I can now verify exactly how early I'm generating positive pressure. It also appears that I can make a simple modification to my megajolt module and simply plug in a certain wire from my a/f meter and it will track the a/f ratio along with the other data. In my recent data-logged run, I was pulling my favorite "test" grade and had to pull back near the top because of the esss turns, and the Scout's handling isn't compatible with the acceleration occurring at that point . Think how you scrub off speed when you enter a sweeping curve, and I also can't keep one eyeball on the a/f ratio gauge. I was at an easy 60 mph (before would be maybe 45-50 mph) and 6 lbs. Boost. Once I am certain I am not detonating, I found a different grade (6%) that should give a straight line shot without handling compromises. I pulled an easy 8 lbs. And then backed off - there was more. That's why datalogging is so important - to coordinate all the data.
 
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Ya like I said "another opinion from the peanut gallery.

You need to worry about timing as much or more than being afr between 12.0 and 11.5.
 
I don't know how to tackle finding optimal timing settings. I'm fairly confident that my basic timing table is close. Running it n/a, I only had a few tweaks to eliminate pings here and there, and then overlayed subtracting 2 degrees per pound boost anywhere I figured I'd have boost. So if anything I May be a bit on the conservative side. I guess one approach would be to select a particular boost (say, 4 pounds), and then incrementally advance until detonation, but that sounds kind of cave man and hard on an engine.
 
There is another member of the IH community that actually has an original Scout 80 (or 800) with the original 152t setup. He lives in the denver area. He recently replaced the puny Holley 1904 1-bbl with a weber 32/26 and said it really perked up the performance. He is also planning on replacing the muffler with a straight pipe. I am urging him to install a boost gauge so he can monitor his boost and stay out of trouble. My hope is he'll chime in here with his progress. Here's a pic of the weber installed. Too bad it's a very small .jpg file.

You can see from the pic that the clearance from the top of the turbo to the ledge/lip at the firewall is probably 3" or so. The comparable clearance in a Scout II is around 3/4", if that. The reinforcing web on the hood's underside is the closest spot.

Pretty cool, isn't it?
 

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