My 22R stroker build has been fully broken in with nearly 3000 miles on the truck, I just took it in for a dyno baseline to see what kind of numbers I'm pushing. I also brought a set of 31x10.5R15 tires to try and get information that's closer to a stock truck.

First, the facts on the build:

- 1981 22R motor
- LCE Performance "Street Stroker" kit
- 0.020"/0.5mm overbore
- Actual displacement: 92.5mm bore x 94mm stroke = 2527cc
- 1mm oversized valves
- Melling 27101 camshaft (specs below):
- Ported head and intake (mostly just smoothing the bowls and plenum, cleaning casting flash, gasket-matching ports. Nothing crazy)
- Flowtech shorty header 19000FLT
- 10:1 compression
- electric fan conversion
- crank scraper
- stock intake manifold and carburetor
- thin late-model style piston rings (part of the stroker kit)

The rest of the drivetrain:
- L52 transmission
- Dual 21 spline transfer cases
- 5.29 yukon gears with a grizzly locker
- 37x12.5R17 Ironman All Country M/T tires

Camshaft specs:
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

The truck in question:



Photos of the build and a few more details are on my build thread: https://board.marlincrawler.com/index.php?topic=105193.150.

The dyno results:

Keep in mind that the large torque spikes at the beginning of the pull aren't true observed numbers, and just an artifact of how the dyno cell loads up. As such, the peak torque numbers written in ink are incorrect. I've written the correct peaks in pencil.



This is an overlay of the best pull with my 37" tires (light colours) and the best pull with a set of 31x10.5R15 tires (dark colours).

As I drive the truck, where I drive it, as observed:
63.3whp@4053rpm, 103lb-ft@2290rpm
With correction factor of 23.2%:
78.0hp, 127lb-ft

Throwing on the 31" tires to see a closer-to-stock result:
74.3hp@4134rpm, 109lb-ft@3170rpm
With correction factor of 22.7%:
91.0hp, 134lb-ft

Wow. That's a pretty wild result. The 37" tires rob an enormous amount of torque, moving the peak torque down almost 900rpm. The difference accounts for 13 peak horsepower, and at least 5hp throughout the whole curve. I'd also imagine that since this is a 2wd dyno, the real world gap is close to double those numbers.

The correction factor is measured by the dyno - taking into account temperature, humidity, and barometric pressure it calculates a correction factor to an ISO standard day at sea level. The corrected numbers are more useful for comparing to other dyno results on different days and at different facilities.

The mud terrains also created some weird data right off the hit, likely a lot of sidewall flex creating vibration until it damps out. Here's the three pulls with 37" tires:



Interestingly, the truck made more power on each consecutive pull, in both sessions. The dyno operator figures that's due to getting the header up to temp, it was quite cold today and the truck loses heat quickly. The gap was about 5lb-ft throughout the pull which is fairly substantial for this engine.

Fluff/Feelings:

It's pretty cool that on a stock-ish tire configuration with altitude correction factor, I'm making pretty much the factory crank ratings at the wheels. With the true 28.5" stock tire the results would look even better.

I do only really care about the torque band from 2800-3500 because that's where I drive it on the street. I expected peak horsepower at a higher rpm, but I've now realized that I didn't account for the increased displacement of the stroker when I picked the cam. I probably could have gone one step wilder without losing much (if any) down low torque, since the increased displacement effectively compresses the power band.

I suppose that the stock carburetor may also be a bottleneck on power at this point, it is a fairly small 2 barrel. I have some edelbrock 4 barrels sitting around which are far too big for this motor, but I could try getting my hands on a 2 barrel and hacking it on for some stopwatch testing.

Overall, the feeling of this motor is pretty good. As the graphs show, it has huge torque off-idle, I can drop it into 3rd gear at 1200rpm with low throttle and putt around town streets. I can also start in 2nd now, gingerly (but why?). The idle sound is much more diesel-like than the stock 22R. Very deep and throaty.

Pulling grades, I'm mostly a gear higher now. I can almost hold the speed limit up I70 through Floyd Hill and feel like much less of a hazard. On the highway, I'm shifting into 5th much earlier/often and on flat sections I can actually accelerate in 5th. Holding 70mph on flats is no trouble in 5th where before I might be working hard at 65 in 4th. The dyno results have corroborated what I felt to be about a 20% gain in torque.

Hauling a trailer, the higher torque is definitely noticeable from a dead stop. I'm not slipping the clutch as much to get moving, and the wider torque band is nice.

Offroad - not a huge difference I've felt. I can lug the engine lower in rpm, but with the gear reduction we use that's not very noticeable.

As for fuel economy, highway has stayed about the same at 16mpg (but now I'm probably averaging 10mph faster) and so has city driving. I think the larger displacement is offset by the fact that I'm no longer driving WOT all the time, so the 15:1afr of cruise is more economical than the 12:1 of power.

Bench racing

- Timing adjustment may yield more power. I'm running 1 degree advanced of FSM, as is common for high altitude setup.
- An adjustable cam timing gear may also yield power, head and block were decked 0.011" which does retard cam timing just slightly
- The factory carb may be an airflow restriction
- The engine may benefit from a larger camshaft
- A good compromise for power / capability could be moving down to the Kenda Kleaver 35x10.5R17 and a set of alloy wheels. That combination may shave 20lbs per corner which is significant.
- My exhaust setup is 2.25" all the way through and hardly a performance muffler. There may be gains there putting in a 2.5" system with a high flow muffler.

Final thoughts:

Building a 22R stroker is probably not worth it in most cases. You're going to get way more power by swapping in a 3RZ or any other engine. I spent about $2500 on this build all in, so a junkyard engine swap would be fairly doable for the same cost. I mostly did this for the originality of the truck, keeping the factory power plant and the legend of the 22R alive. I've pretty much just clawed my way back to stock tire size power on 37s, the truck is probably still slower than a bone stock '81. I do enjoy the accomplishment of building an engine start to finish, adding it to the list of all the other drivetrain components I've rebuilt on this truck.

Thanks for following along, I hope this information is helpful.

All I saw was that you can hold the speed limit on Floyd Hill on I-70. If that with 37inch tires you have been successful.  I’m pretty sure that my ‘85 truck on 32inch tires would have been reduced to 3rd gear. My 4Runner was actually pulled down into 2nd on Vail Pass eastbound if memory serves and again the the Eisenhower tunnel approach.

For a stroked, carbed 22R with nothing more than adding the stroke I'd look for a 15-20 lbft increase. Wouldn't consider power increases without a bit more work. You didn't mention the generation of 22R you used. The later model is better for performance really. From what I see here you're on par with what would be expected.

Factory carb in vactory tune isn't good enough for many mods, unless you've done some extensive work on it you'll never get the potential out of your build. BRD Racing mods the 22R carb for circle track, might be able to help you there. I would suggest a Weber 38DGES if you want a better low end torque or a 40DFEV for mid to upper power with a single 2 barrel. An Offy or Cannon manifold will help a bit as well. Otherwise a set of side draft carbs would be the way to go, lot to get into there. Learn to tune the carb.

Maybe I missed it, but headers?? The 22R really likes improvements to the exhaust. If you have the early exhaust manifold, the "reactor" type, get the type with the 4-2-1 design, it'll help.

Cam? Bigger is not always better. Intake ports will dictate how much cam you can get away with. I'd look for a cam with more gross lift, maybe up to .460" My favorite cams can't be had any more, that company is long gone, but there is WEB cams that can get you a good grind with .443" lift and a 208 in and 220 ex @ .050". I'd have them grin the intake at their 216 dur .050" with .441" lift with that 220 ex. Be careful with the cam duration when cranking big tires.


A cam will MOVE your torque better than uncrease it. The intake port can do more if done right.

Combustion chamber and quench (later engines) need some attention as well. At least have the valves unshrouded and polish the chamber. Do it right and it could be worth as much as 5lbs of torque from your 22R. The higher your compression gets, 10-1 is pretty high for a 22r, the more attention you need to pay to the combustion chamber.

I used to do a bit of work on the distributor. The mechanical curve can be adjusted with a drill, Dremel and some tungsten. Springs can be gotten from the Chevy and Ford distributor kits. Ditch the vacuum advance. I've found the best performance curve peaks at 28-30 degrees total with my 22R builds with an initial of 8-10 degrees initial. Don't listen to the racers if you plan to drive this thing everywhere, locked at 30 degrees only does well if you're racing.

Sorry, I get excited over 22R/E builds. My favorite 4banger lump. Well, next to the 4AGE anyway.

Good points deuce. The carb is definitely going to be the low hanging fruit for next upgrade. I've looked at the Holley Sniper as an option, the Weber would be a far cheaper stop-gap. I do have to pass emissions every 2 years and the Weber isn't certified for that, but I've passed the 2-speed idle before with a Weber 32/36 in my '79 Subaru when the greasy teenager running the test wasn't jive enough to notice it during visual inspection.

I did note in the OP that I'm running a Flowtech 19000FLT header and the whole motor is a 1981 configuration.
Soon I'd like to do some backroad stopwatch testing with a timing sweep to see how much total advance the engine wants, if there's anything to be gained there.

RE the head gasket - I did use a fairly cheap gasket kit (ITM ENGINE COMPONENTS 0901553) including their head gasket. If it fails, not a big deal to R&R it and do some more head work while I'm in there.

I hate to poke a hole in your result theory regarding stock tires and the stroker rebuild, but with the 31's and 5.29's, you are 22.5% over geared compared to the stock 4.10's and 28.5" tire, so the 91HP result with 31's is not close to what the stock tire/gears would be with the stroker motor, your results with the 37's are.  The reason for this is that the difference between 28.5's and 37's is 23%, and the difference between 4.10's and the 5.29's is 22.5%.  The stock tires/rim having less rotational mass than the 37's should put the stock tire/stroker combo above the 78HP corrected altitude, but not by more than a few ponies.

Given the info about the dyno correction for altitude only and not drivetrain loss, your actual HP/torque gains should be higher.  Using the corrections that 22re Performance used for drivetrain loss in their the '91 truck with a shell and heavy lumber rack of 23.6%, which is probably close to what should be used with the 37's MT's, it puts your HP at the crank at 96.4HP or virtually the same as the stock engine HP but at 800rpms lower.  The stock '81 22r was rated at 97Hp and 127ftlbs at the crank at 4800rpms.  While the HP increase at the crank is non existent, the torque increase is, as your corrected torque for drivetrain loss would be 157ftlbs at the crank at 4000rpm.

If you want better overall street performance for daily driver type uses, a set of 35's would perform better, they about 5% smaller than 37's, and the 5.29's are about 4% over geared for 35's, when compared to stock tire/gear combo.

Do you have a link to the 22re Performance drivetrain loss numbers? I'm not sure I understand how a shell and lumber rack factor into that.

Here is the 22re link https://www.youtube.com/watch?v=r-f-oWhNCc0. 
They used two separate drivetrain percentages, one for the '87 4-Runner, and another for the '91, I am assuming they used a slightly higher value for the '91 due to the extras making it weigh more than the '87.  The weight of a difference of one vehicle to another running the same engine/trans will effect how much engine power reaches the rear wheels, just as axle ration and tire size do.  The general rule of thumb for drivetrain loss is 15-20%, generally 15 for manuals and 20 for auto's, not exactly sure why they used a more specific value. 

I'm not sure I can wrap my head around why gear ratio would make a tangible difference on a Mustang eddy-current dyno. It's much more straightforward in my mind on a dynajet inertia dyno, where lower gear ratio (or smaller tires) actually yields less observed horsepower. I actually wrote a much longer reply waxing poetic on the kinematic math that goes into how these dynos calculate power, but I'm not 100% on it so I don't want to muddy the waters.

You seen the difference results between the 37's and 31's, the results would again have been higher with 28's, or lower had you put on a set of 40's.  You would also get a higher HP value if you ran the test in 1st or 2nd gear and lower had had ran the test in 4th or 5th, the same would be true with running the same tire size at higher and lower gear ratio's.  The reason for this, is that gear ratio's be it transmission or diff gears, effect how much of the engine's power is put to the ground through the rear wheels, which is exactly what dynos measure to get a WHP values.  This is why when you take your stock Toyota and throw on some 37's you lose all the power you had when it was on 28's, the engine is still putting out the same HP at the flywheel, but the power you were once putting to the ground with stock tires, is now being absorbed by the larger wheels before they even begin to spin.

I wish I could get my hands on a bone-stock truck on 37s and 5.29s locally to do a true comparison. I put out feelers locally when I booked my dyno session but didn't have any takers.

It is my understanding that your rig is set up now with 5.29 yukon gears with 37x12.5R17 Ironman M/T's? If you aren't running 5.29's, then your results with 31's would be closer to stock numbers.

Just for gits and shiggles I ran some numbers in my dyno software.  See attached Excel sheet below.

The 22RE factory stock is just for a reference based upon my running conditions:

Barometric Pressure: 29.82
Intake Air Temp: 70d F
Dew Point: 37d F
Elevation: 1,000 ft
Fuel Octane: 87


a1gemmel's specs (22R stocker) as close as I could get, Longmont's average yearly weather:

Running conditions:

Barometric pressure: 29.82
Intake Air Temp: 81d F
Dew Point: 42d F
Elevation: 6,000
Coolant Temp: 195d F
Fuel Octane: 87

I have never seen a flatter and longer HP curve in any of the comparisons I've done.

His peak torque is in a nice sweet spot for RPMs.

If stroking a 22 does this... I'm excited to find out how LCE's 22RE Stroker's numbers will look like!

Is it worth it to stroke a 22?? HELL YES!!

Gnarls.