Topic: Project: The '81 "Yoter"

[Ritchie]

Very nice... what tires are you running?

[a1gemmel [OP]]

37x12.5R17 Ironman All Country M/T, aired down to about 4 psi in that video. I've been pretty happy with them so far, for a "no-name" tire from Ebay the performance is really good and the road noise is minimal.

[a1gemmel [OP]]

Whelp, a couple months ago I wrecked the motor in the poor old nugget. It was parked in the backyard on mulch for a month and I guess the oil pan developed a crack (again!). I drove it to the gas station and it started knocking. It has an oil pressure gauge but I never looked at it. Pulled the dipstick, bone dry. Pulled the motor and tore it down the same day, number four rod journal spun a bearing and none of the others looked too hot.







I fired off the parts cannon and ordered a street stroker kit from LCE, took quite a while for the pistons to arrive. Fair enough since they are made-to-order custom units. Nice rods too. Also, LCE now uses 86+ ringlands in all their pistons, meaning it gets the thinner ring pack that should be worth a few horsepowers clawed back from parasitic loss.





After that, the whole works went to the machine shop. Block was decked and bored 0.020" over, head was decked and 1mm oversize valves installed. Also had the flywheel machined while I was there. When I got the head back, I did a basic port job. Gasket matched the intake, honed out the exhaust, cleaned up the bowls and removed all the casting flash. I know head porting is a contentious subject so I'm not posting any photos of that. Let me just say that there's almost no chance the minor changes I did could have "ruined" this head, I wasn't hogging out material all willy nilly.

Progress has been slow putting it back together what with the hundred other projects I have on the go, but here's where we're at.



It's getting there... to recap, here's the parts list:

LCE street stroker kit, 9.7:1 pistons 0.020" over. (2366CC -> 2527CC)
Crank scraper
1mm oversized valves
"Ported" head
Melling 27101 "Heavy Duty/Towing" camshaft
Flowtech shorty header 19000FLT

I hope to see 15-20% more torque at 3000-3500rpm, what do you guys think?

[Gnarly4X]

Wow..... BIG Project!!

Can you provide the camshaft profile/specs?

It was bored 20 over.  How much was the block decked?

What is the measurement between the top of piston and the deck?

What head gasket did you install?

I'm a big instrument fan, so I look at the gauges all the time, and at the oil pressure gauge EVERY time I start the engine.

Gnarls.

[a1gemmel [OP]]

The specs for the Melling 27101 taken from Summit are:
Intake Duration at 050 inch Lift: 214
Exhaust Duration at 050 inch Lift: 224
Duration at 050 inch Lift: 214 int./224 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.417 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.429 in.
Valve Lift with Factory Rocker Arm Ratio: 0.417 int./0.429 exh.
Lobe Separation (degrees): 110

Block and head were decked a total of 0.011". I know both were virgin before.
Honestly I didn't measure the deck clearance, I would expect it to be 0.006" less than stock numbers.
Head gasket is an OEM + 0.010" thickness set from rockauto. I did that to avoid needing an adjustable cam gear. Time will tell if a generic gasket holds up I guess.
 

[Gnarly4X]

Thank you.

I'm just curious...

What intake and carb are you going to install?

I can plug these numbers in my dyno software and see what the torque and HP numbers look like.

Gnarls.

[a1gemmel [OP]]

Factory for both.

When I'm done I'm going to take both this truck and my 1986 22RE 4Runner to a dyno for baselines, if I consider the 1981 stock power (97hp) vs the 1986 (113hp) it should be possible to draw some conclusions about gains. It will be skewed a bit since the 4runner has an LCE header and we can't know how much exactly that's worth.

[Gnarly4X]

Hi a1gemmel,

I ran some quick numbers this afternoon in my Performance Trends Engine Analyzer v3.2.
This is just a snapshot of the “data” and may not be what a SuperFlow SF-902S would produce.

Based upon your parts selection, the numbers you provided, and your work on the head, I calculated as close as my experience at doing this since the year 2000 will allow.

9.5 CR. The cam profile has 4.7 degrees of overlap, so it probably will have a relatively smooth idle, perhaps a slight lope?.

I used the same Running Conditions as my location that I’ve used for years, as a base.

I can change the Running Conditions and they will affect the numbers.

Barometric pressure:  29.82
Intake Air Temp: 80d F
Dew Point: 37d F
Elevation: 1000 feet
Fuel Octane: 87

RPMs Start: 1800 to 5400
Number of RPMs 10
RPM Increment: 400
Peak HP at RPM 5000
Pk Tq: 157 – Avg. Tq: 142
Pk HP 131 – Avg. HP 97.8
Peak Tq: 157 at 3400 to 3800 RPMs
Peak HP: 131 at 5000 to 5400 RPMs

It takes me about an hour+ to run the numbers by every 100 RPMs.

Gnarls.

[a1gemmel [OP]]

Thanks Gnarls, that would be a pretty good outcome.

Take out 20% for drivetrain, 4% per thousand feet at 6k elevation + 1k density altitude on average - that would leave me with (131 * 0.80 * (0.96^7)) = 79WHP sitting on my driveway. All this effort to make a rounding error of the HP I'm shooting for with my 409 SBC build 

[Gnarly4X]

Hey a1gemmel,

At 6,000 feet elevation, ambient air temp at 70d F, all else the same:

Barometric pressure:  29.82
Intake Air Temp: 70d F
Dew Point: 37d F
Elevation: 6000 feet
Fuel Octane: 87
RPMs Start: 1800 to 5400
Number of RPMs 10
RPM Increment: 400
Peak HP at RPM 5000
Pk Tq: 135 – Avg. Tq: 118
Pk HP 105 – Avg. HP 81.1
Peak Tq: 135 at 3400 RPMs
Peak HP: 105 at 5000 RPMs

Gnarls. 

[Gnarly4X]

Just for a comparison.... this is what a STOCK 22R looks like at elevation:

Barometric pressure:  29.82
Intake Air Temp: 70d F
Dew Point: 37d F
Elevation: 6000 feet
Fuel Octane: 87
RPMs Start: 1800 to 5400
Number of RPMs 10
RPM Increment: 400
Peak HP at RPM 5000
Pk Tq: 108 – Avg. Tq: 95.9
Pk HP 81.3 – Avg. HP 63.9
Peak Tq: 108 at 3000 RPMs
Peak HP: 81.3 at 4600 RPMs

Gnarls.

[Gnarly4X]

Here's what a 1986 STOCK 22RE looks like...

Barometric pressure:  29.82
Intake Air Temp: 70d F
Dew Point: 37d F
Elevation: 6000 feet
Fuel Octane: 87
RPMs Start: 1800 to 5400
Number of RPMs 10
RPM Increment: 400
Peak HP at RPM 5000
Pk Tq: 119 – Avg. Tq: 99.3
Pk HP 81.0 – Avg. HP 65.8
Peak Tq: 119 at 2600 RPMs
Peak HP: 81.0 at 4600 RPMs

Gnarls.

[a1gemmel [OP]]

Some progress



Crank scraper because it was cheap and every horsepower counts on these pieces of junk 







Sandblasting and painting all the pieces takes more time than any other part of the assembly but it's sure looking purty.

[a1gemmel [OP]]

I also built a trailer for hauling the toys around for longer trips - next time I go to Moab I don't really feel like white-knuckling the yoter through the mountains for 8 hours again. Plus I'd feel better trailering it out to some of the more wicked trails I'd like to try next year. Started with a bare RV frame, cut 3 feet off the end and beavertailed it. I'm in it probably $1900. My advice for other folks - avoid these old RV platforms, it's not really worth it for most applications. One of the hubs had 2 broken lug bolts, I failed to extract them so the hub had to be sent out to a machine shop. That side had left handed lugs so I just had them make all 4 RH with helicoils. The 70's Lafayette/Dayton RV hubs are pretty much unobtanium so repair was the only option. They also use 1/2"-13 lug bolts which aren't made any more, and on a wheel pattern that isn't made anymore either. All that and the deck is only 6'2" wide, just enough for our minitrucks but forget about anything wider. Still, for the money I have in it it'll do what I need.
 

[Cheesemaker]

Looking good buddy.  I recently picked up a new replacement 22R to replace the rebuilt turd I had originally put in my truck.  And it's .040 over, crank scraper, balanced bottom end.  And first thing I noticed, the crank scraper adds depth to the pan a little, like an extra 1/2 quart of oil.  And if you run a larger oil filter you will you will put in like 5.5 quarts of oil.  A balanced motor, and a crank scraper definitely makes the motor smoother on the revs. 

[a1gemmel [OP]]

Good point on the scraper adding oil capacity, didn't even think about that.

[a1gemmel [OP]]

Went down hard for a while - big sinus infection that lasted 3 weeks, stung by 15 wasps and was the Michelin man for a few days, put an exacto knife through my hand and got a bunch of stitches. Anyways, we're back on track. Motor should drop in tomorrow inshallah.

Spent some time building the MegaBracket™, this will run my welding alternator and a york 210 air compressor. So much easier doing this while the engine is out.





Truck is pulled in and ready to accept the powerplant.



I also spent some time working for the enemy - my friend's sweet J10 rolled in for a header install and I fabbed up a duct for his fuel cooler after having a good laugh at him for how ineffective his mounting location was.





I also made him this cowl hood a few months back, it's been a huge game changer for air and coolant temps bombing up I70.

[a1gemmel [OP]]

Engine is in and mostly hooked up, might even start it tonight. Fabbed up a battery tie down since the factory one really doesn't fit my battery. I'm also going to an electric fan which is probably worth more horsepower than any of the other mods!

[a1gemmel [OP]]

Foiled, ran out of mig wire welding up the exhaust connector to the header. To be resumed on Wednesday.

[Gnarly4X]

Foiled, ran out of mig wire welding up the exhaust connector to the header. To be resumed on Wednesday.

Running out of mig wire is like running out of TP....... happens! 

Gnarls.

[a1gemmel [OP]]

Break-in went reasonably well - engine fired first crank with the distributer plugged in after cranking to prime oil pressure. I ran it for 15 minutes varying the RPM with a friend watching the engine. It sounded a bit rough which I'm going to attribute to timing/valve lash until I have reason to believe otherwise. Next chance I have to wrench on it I'll change out the break-in oil, check the cam/lash, check the compression, and actually set the base timing.

[a1gemmel [OP]]

We're looking pretty damn good now fellas. Oil was minimally shiny, got the timing dialed in (was way off on the break-in), coolant is bled, lash checked out good, compression came back at an adjusted 160psi all around. Although I've just driven it a few miles I can tell that it's got a noticeable increase in overall pep. Haven't taken it over 4k rippems yet. Once I get some midgrade in it I'll throw some more timing in it, I set to factory spec but I know I can already add 2-3 degrees for altitude and then maybe some more on top of that.

Still a few more things to button up but I'm feeling good about it.

[a1gemmel [OP]]

Also, I don't think I ever mentioned it but we had some brutal hail in the spring and the topper was cracked in at least half a dozen places. It'll be back on after I can do some fiberglass repair to it, I can't get rid of that signature look!

[a1gemmel [OP]]

Two more things that came to mind:

1. Look at these two piston/rod combos. One of these is for my 100hp 22R. The other is for my 500hp 409 small block chevy. Which is which will surprise you 



2. As you might have caught in that photo, neither of those pistons have stock-style rings. LCE has moved to using late-style ring packs for all of their pistons, which changes to 1.5mm first/second rings as opposed to 2.0mm/2.5mm first/second rings in the OEM pistons. Hot Rod did a test* a while ago of thin piston rings in a small block chevy and found about 8 hp gain throughout the curve. Let's extrapolate that to 4 hp on an inline 4 such as the 22R. Every bit counts 

* : https://www.youtube.com/watch?v=-29IWc-zrv8

[a1gemmel [OP]]

Working on welding in some frame stiffeners and shock hoops, I started one side a while ago and never finished it. I'm throwing some heavy duty air shocks in to prop up the front suspension, my homebrew SUA setup has sagged quite a bit and I'm not liking the ride too much. Fun experiment and I don't regret the learnings I got from doing it, but I'm going to three-link the front end soon.







The angles look goofy at full droop but I promise it works 

[a1gemmel [OP]]

Air shocks are a big success, major improvement to front end ride quality. Pumped them up to 80psi and they level the front end (truck is sitting about 3" higher than normal without the topper and all the gear in it).
Interesting thing is that the fittings Monroe supplies make you tee the two shocks together and inflate them together. I suppose that's actually a benefit for articulation since pushing one tire up forces air into the opposite shock and pushes the other tire down.

Next up is fixing the tailgate area of the bed. I bet most of you California folk are lucky enough to never have experienced sitting on your tailgate and having it break right off with a chunk of the bed...





This chassis is beat, man... Still, we persevere.

[a1gemmel [OP]]

Hinge brackets - just steel flat bar with holes drilled and nuts welded on the back. Notched where I thought they might fit, mount the tailgate, tack in place.



Fully welded, ground flush, slathered with an inch of rustoleum.

[a1gemmel [OP]]

The '86 Camaro I parted out had a great interior - I thought that would all be the quickest to sell but I've had these seats in my storeroom for almost a year now. So, I threw them in the truck. Comfy buckets and they have back adjustment which offers the benefit of comfort as well as access to the back of the cab. I made 1-1/2" spacers for the front mounts to get them at the right angle for the pickup.

 

[a1gemmel [OP]]

I had a friend in the truck who has driven it before and he thinks 20% gain in power. Dyno soon...

[a1gemmel [OP]]

Putting light sipes in the tires in anticipation of the coming winter, takes about 40 minutes a corner and seems to make a big difference on icy roads.