'55 R-122 rehab


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Golden Jubilee
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Post Tue Feb 20, 2018 5:03 pm

Re: '55 R-122 rehab

Thank you.

You'd think I lived in BC or NL for all of the rain we've been getting (the last few days) and are slated to get over the rest of this week. The machine shop won't likely get to planing my manifolds for 1-2wks. That's alright though.

Even with all of the rain I wrote a few chips and drove them today. :whistling2: I might have forgotten to mention that I bought a chip reader/writer, some good tuning/data logging software, and a handful of chips. ;)

My primary focus with the 1st chip was to make the bottom end (20-60kPa from 400rpm -1600rpm) stronger. I had to slip 2nd gear, or use the Granny gear to get the truck going previously. It's still a bit soft, but much better now. With the 2nd chip I started worrying about getting my fuel pressure back down to a more manageable level. I don't know exactly where I'm at, but I do know that I'm down below about 15psi at the moment (current gauge stops here; I'll change it out for a 0-15 when the rain lets up). Once I get the fuel pressure levels back to stock (12-13psi) with good BLMs and AFRs I will work on strengthening the bottom end. By the logs I have I believe the engine still wants more fuel down low. I'm hoping to get a another data logging run in this afternoon and possibly a 3rd chip before the day is done.

As an utter newbie to the "tuning" game I need to keep reminding myself," One thing at a time Dummy". :t3724:
Last edited by VWJake on Thu Feb 22, 2018 5:55 am, edited 1 time in total.
'55 IH R-122- BG265 w/TBI fuel injection
'64 Porsche 356 C
'68 and '73 BMW 2002s
'86 Cadillac Coupe Deville
'14 VW Passat SE TSI
3 Vintage Sears garden tractors ('66-'74)

Golden Jubilee
Golden Jubilee

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Joined: Fri Nov 30, 2012 6:32 am

Location: Minnesota

Post Tue Feb 20, 2018 5:15 pm

Re: '55 R-122 rehab

Jake,
You amaze me with your knowledge and workman ship, and all the work you have done.
kevin
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Golden Jubilee
Golden Jubilee

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Joined: Sat Jun 29, 2013 12:58 am

Location: Central IL

Post Tue Feb 20, 2018 6:25 pm

Re: '55 R-122 rehab

Kevin,
I too am in total admiration of the work you’ve done to your truck. The risk ( in my eyes) your took blowing your truck was/is no small feat. I have the utmost respect for you for taking the plunge on that one. I've always had a healthy fear of an improperly fueled turbo engine. I’ve seen boosted TBI injected engines... *wheels turning* lol

I can’t take much credit for the EFI swap. Folks have been putting this fuel system on any and everything for decades now. I found some IH specific stuff on Binder Planet in the FI forum. That is where I found the seller of my initial "chip". There is some contradictory and possibly misleading information (generally from the same keyboard...) and some "I'm superior" attitude over there, but if you can get past all that there is some really good how-to's to get you started. After hours and hours of reading on thirdgen.org, Gearhead EFI, and others I still don't know squat, but I can tell you for certain that I would not "buy" another chip again. For less than $200 I can now write/re-write chips to my hearts content.
'55 IH R-122- BG265 w/TBI fuel injection
'64 Porsche 356 C
'68 and '73 BMW 2002s
'86 Cadillac Coupe Deville
'14 VW Passat SE TSI
3 Vintage Sears garden tractors ('66-'74)

Golden Jubilee
Golden Jubilee

Posts: 1054

Joined: Fri Nov 30, 2012 6:32 am

Location: Minnesota

Post Tue Feb 20, 2018 6:36 pm

Re: '55 R-122 rehab

Thanks,
When I ordered the turbo, I picked up a short block BD at the same time, I don't think I could grasp the FI. Still 6 volt here, I'm gettin old and for sure don't energy your have.
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Golden Jubilee
Golden Jubilee

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Location: Central IL

Post Wed Feb 21, 2018 7:23 am

Re: '55 R-122 rehab

If you can figure out how to pressurize a carb and get it to deliver the right amount of fuel all of the time I think you could manage a bunch of 1s and 0s. The 6v thing on the other hand...
'55 IH R-122- BG265 w/TBI fuel injection
'64 Porsche 356 C
'68 and '73 BMW 2002s
'86 Cadillac Coupe Deville
'14 VW Passat SE TSI
3 Vintage Sears garden tractors ('66-'74)

Golden Jubilee
Golden Jubilee

Posts: 1054

Joined: Fri Nov 30, 2012 6:32 am

Location: Minnesota

Post Wed Feb 21, 2018 10:24 am

Re: '55 R-122 rehab

I am running an old school type draw thru system, the blow thru is another animal. One of the guys with a blow thru explained that system one day, fuel pressure has to be 10 lbs higher that the boost, modified carb, and the newer electronic stuff he can retard the spark when in boost.

Golden Jubilee
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Location: Lyman, IA

Post Wed Feb 21, 2018 10:42 am

Re: '55 R-122 rehab

You can build a box around the carb, but then the controls must pass thru the box, or you can modify the carb to blow air around the throttle shaft (choke doesn't matter as the only thing that would leak was air). Fuel pressure needs to be regulated to normal fuel pressure plus what the boost pressure is at any one time, so fuel pressure regulator needs to be variable, controlled by boost pressure.
Blow thru allows for an aftercooler and therefor higher boost pressure, but is more work.
Blow thru is a lot more work, but if you are going to do some serious boosting, it is better.
Most electronics are 5v so can be modified to run on a 6 v system, The problem is the IAC motor and Injector solonoids, are 12V IIRC. Simpler to change to 12 v and use a solid state 12-6 convertor to run the gauges and wipers.
I had started down the road to build a turbo Slant 6 many years ago, almost 40 now, never got it done, and good rust free "A" bodys were getting hard to come by.
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Golden Jubilee
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Post Sun Feb 25, 2018 6:24 pm

Re: '55 R-122 rehab

I've managed to get the fuel pressure back down to 13psi. (good factory GM setting), I created the adapter to mate the 2bbl TBI unit to the 2bbl intake- Thanks again PAULH for the manifold! The manifold made a measurable difference (on the butt dyno) in mid-range and top end over the small diameter 1bbl mani and adapter. I deleted the preheat flap/spring from the exhaust manifold and sealed those holes to reduce the chance for fresh air leaks in to the exhaust stream (skewing the o2 and WBo2 readings). The assembled manifolds went to the machine shop for planing and came back in 2 days. Turns out they had another manifold to mill so with the machine set up already mine got bumped up on the list.

Still by no means a pro at this stuff, but I burned and logged 6 diff chips today. Quite pleased with the outcome.

I've got the VE (Volumetric Efficiency) tables tuned to the point that the BLM (Base Learn Mode; long term trim adjustment to VE table fuel request values per RPM/MAP kPa value) tables are within 4points of stoich. (128). Now that the fuel seems to be happy I'll drive it around for a few days logging data and start formulating a plan to add some timing. I wouldn't be surprised if it'll take at least a few degrees across the board without any trouble.

While most of my off-idle stumble (for my easy going daily driving style) has been tuned out with fuel adjustments I still feel that it is "soft" off idle. I haven't tried it yet, but I don't think I could just bury the pedal and light-em-up. I suspect there is likely a healthy bog before it figures out whats going on and gets with the program. I'll do some testing next week and monitor progress with the timing tuning. If joy is not found I will be looking at "AE" (Accel Enrichment). Basically it's a digital accelerator pump. Then there is the matter of a sorta "flat" acceleration in the upper RPMs. I know it's not a racecar, but there's another item to tinker with that may help fill out that area. It's called "PE" (Power Enrichment) or power valve. The idle is a bit rough as well. There's a pile of other settings to monkey with to possibly improve that, but I'm not going to worry about that for now. As it is the truck idles around 700 and I'm happy with that.
'55 IH R-122- BG265 w/TBI fuel injection
'64 Porsche 356 C
'68 and '73 BMW 2002s
'86 Cadillac Coupe Deville
'14 VW Passat SE TSI
3 Vintage Sears garden tractors ('66-'74)

Golden Jubilee
Golden Jubilee

Posts: 4032

Joined: Thu Nov 29, 2012 9:28 pm

Location: Lyman, IA

Post Sun Feb 25, 2018 6:44 pm

Re: '55 R-122 rehab

TBI needs some "carb heat" to vaporizes esp at low throttle settings. The low fuel pressure of the TBI unit mean the fuel is in bigger droplets then higher pressure FI. Does it have a heated air snorkle? Look for frost around the edges of the throttle plate, which can keep injected fuel in liquid form by cooling at the pressure drop across the throttle. TBI has many of the same problems as a carb in terms of cooling around the throttle plate, but will respond to the same fixes (hot spot, heated air intake) as a carb would.
The Hot Spot on IHC manifolds aren't real aggressive, you might want to try re-installing it.
Might try playing with the advance curve off idle as well, on a mechanical carb'd engine, I would say advance with an off idle bog, but that is without the benefit of an O2 sensor in the exhaust, you have more info to look at and decide if it is lean mixtures (needing advanced timing) or poor fuel mixing/vaporization.
I'm sure you will solve it.
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Golden Jubilee
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Joined: Sat Jun 29, 2013 12:58 am

Location: Central IL

Post Sun Feb 25, 2018 7:31 pm

Re: '55 R-122 rehab

In a manner of speaking the preheat is still there. It just lacks the diverter flap to force the exhaust flow directly against the bottom of the intake. I will monitor the temps. I’ve already pondered creating a new adapter with cooling passages built into it if required to provide more
Pre-heat if needed. Time will tell. I’m hoping to make some more good progress soon.
'55 IH R-122- BG265 w/TBI fuel injection
'64 Porsche 356 C
'68 and '73 BMW 2002s
'86 Cadillac Coupe Deville
'14 VW Passat SE TSI
3 Vintage Sears garden tractors ('66-'74)
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