A while back my 22RE started having some terrible rocker arm noises work got busy havent had time to tear into her yet. So this winter when work slows down a bit I'm going to pull the engine and get it preped for a vist to a machine shop. Questions I have. When I have the machine shop bore the cylinders I don't want too go to big and have the cylinder walls so thin they could blow out. I'm thinking 40 over. Would like advice on bore size. I'm also going to order a new head, camshaft, and rocker arm assembly from lceperformance. What is everyone's thoughts on their Pro torker head kit? I've also been told if I install a heavier flywheel I can produce more torque. Has anybody installed a heavier flywheel from lceperformance for torque gains, and does that actually work? Lastly does anybody know the performance gains I may get installing a header? I've been told I can get slightly more power and slightly better fuel economy is this true? Any advice and constructive criticism on this rebuild would be greatly appreciated thank you very much.

For what it's worth... I ordered a stage 2.5 long block from 22RE Performance and bolted a LC Engineering header on my 85 Sr5 and it runs great.  If you are looking for HUGE gains in torque and HP then it may be less expensive doing some sort of engine swap for a larger more powerful motor. Looking back I wish I would have done a swap in mine. The gains were minimal and the cost were excessive. Don't get me wrong they build one mean 22RE and it does feel like it has more power over the one I replaced but I wouldn't do it again.     

For what it's worth... I ordered a stage 2.5 long block from 22RE Performance and bolted a LC Engineering header on my 85 Sr5 and it runs great.  If you are looking for HUGE gains in torque and HP then it may be less expensive doing some sort of engine swap for a larger more powerful motor. Looking back I wish I would have done a swap in mine. The gains were minimal and the cost were excessive. Don't get me wrong they build one mean 22RE and it does feel like it has more power over the one I replaced but I wouldn't do it again.     

For what it's worth...   

As I said… everyone has an opinion.

Installing an LCE head (4-in-1) is a good header, but known to be better for high RPMs… not useable unless you are racing your vehicle and want to sacrifice some lower RPM torque.  The DT header would have been the better choice for that engine…. Just my opinion.

Gains and cost is all subjective.  Based on my recent experience gains and cost going with 22RE Performance long block IS way less expensive and WAY more reliable than practically anyone else’s DYI rebuild.

Engine swaps for “a large more powerful motor” are more often touted as easy and less inexpensive… they are not always.  The hours invested from start to finish and the actual dollars spent are almost always under estimated.

Gnarls.

Generally you should only ever bore to the next size up which cleans up any scratches or pitting in the walls. The extra displacement you gain from boring bigger is not going to give you any extra power. You want to only bore as much as necessary so if you need to rebuild it again in 300,000 miles (unlikely) you'll still have room to go.

I have the 35 lb flywheel from LCE. It's a bit pricey for what it is. It is not at all noticeable on the street, maybe a bit harder to stall off the line. Where it shines is off road. The truck is very hard to stall. It doesn't add torque as LCE claims, just adds rotational inertia and smooths out power down low. Without touching the throttle, the engine will go down to 250 - 300 RPM and keep driving. Stalls when it gets down to around 200 RPM. If I had it all to do again would I buy it? I'm not sure. It's pretty expensive. But I do have it and it does help and I'm happy with it.

Don't have much to add for your other questions.

Boring a 22 block to 60 over can be reliably done and will produce a very noticeable increase in power.  If my 60 over bore goes 200,000 miles, that’s about 10 years for me.  I’d rather have the extra power for 10 years than be concerned about rebuilding a 43 year old engine block.  A stock 22RE with a .060" over bore will produce about 5 lbs more peak torque, and average of about 4 more lbs of torque between 1800 and 5,000 RPMs, and will increase the peak HP by about 1 HP.  It is my opinion that 5 lbs. of increased torque at 3000 RPMs will be very noticeable in a stock 100 HP engine.

By the way... high performance 22 race engines are punched 80 over.  However, they are typically rebuilt after one season of racing.

The heavier flywheel DOES increase torque.  Lugging an engine down to 200 or 300 RPMs is foolish, especially when 4-wheeling.  Oil pressure drops too low for safe lubrication protection and there is virtually no usable torque at 250 RPMs.

Gnarls.

The hypothetical gains from boring 0.060" over are pretty small. It's also anyone's guess whether you could truly feel 5 ft-lbs increase. So I'm not going to argue that.

The flywheel does not add torque. Torque is force x distance. The force comes from the fuel air mixture exploding and pushing down on the piston. The distance is the offset from the rod big end centerline to the crankshaft centerline. None of that changes when you change the flywheel. The flywheel adds rotational inertia. The flywheel absorbs energy by increasing rotational speed, and released energy by decreaseding its rotational speed. When compared to a ligher flywheel, a heavier flywheel can absorb more energy at the same rotational speed, and correspondingly, it can realease more energy for the same reduction in rotational speed.

I agree 100% that lugging the engine down to 200 RPM isn't a good idea for exactly the reasons you stated. It was just a demonstration of how the engine is harder to stall with a heavier flywheel.

Rotational torque… a flywheel releases stored energy by applying torque to a mechanical load,  You can call it what you want.  I’ll stick with “torque”, you can call it inertia.

In my 22R I could “feel” and see the RPM drop by 100 to 200 RPMs when I turned on the AC compressor.  How many pounds of torque were required to spin the AC compressor.  I could also feel and see the RPMs drop when I turned on the lights.  How many pounds of torque does it take to spin the alternator under load?

Can an engine dyno measure a change in 1 HP?  How much torque equals 1 HP?  Is that a “hypothetical” measurement?


Gnarls. 

Physics police here! Others have explained some of this but I will shove my oar in as well 

Rotational torque… a flywheel releases stored energy by applying torque to a mechanical load,  You can call it what you want.  I’ll stick with “torque”, you can call it inertia.

Torque and inertia are completely different things. It's a free country and you can call them what you want, but these discussions will be much clearer if we all stick to standard definitions and remember the difference .

In my 22R I could “feel” and see the RPM drop by 100 to 200 RPMs when I turned on the AC compressor.  How many pounds of torque were required to spin the AC compressor.  I could also feel and see the RPMs drop when I turned on the lights.  How many pounds of torque does it take to spin the alternator under load?

Torque is not measured in pounds, rather in foot-pounds.

Can an engine dyno measure a change in 1 HP?  How much torque equals 1 HP?  Is that a “hypothetical” measurement?

You need to know the engine RPM to make that question meaningful. The equation is:

Horsepower = (Torque*Rotational Speed)/5252. Torque needs to be in foot-pounds and speed in RPM for this to work.

We shall now prove that a heavier flywheel does not increase the torque output of an engine.

Take a stock 22R with stock fuel system running at a fixed RPM. it can only suck in air and fuel at a limited rate. Therefore there is a theoretical upper limit on the power output of this engine, because there is limited energy stored in the fuel and it comes in at a limted rate.

Suppose that adding a heavier flywheel increased torque. By the equation above, horsepower would also have to increase. But there is no upper limit to this; by adding heavier and heavier flywheels to the engine, we could get horsepower beyond the theoretical upper limit to it's power output. We would have violated the conservation of energy.

Spoiler: Conservation of energy holds. Heavier flywheels may well help the engine not stall, but they do not increase torque output.

Thanks everyone for reading. Have a nice physics packed day! 

Lewis,

What do you call the FORCE that inertia applies to a rotating mass?

Gnarls.

...  a heavier flywheel does not increase the torque output of an engine.

True.

Gnarls.

Lewis....

Are we talking about a rotating flywheel?

In physics the mechanical work applied during rotation is the torque times the rotation angle:  W=r*theta.

The word torque is the correct word.

Gnarls.

I see a few posts about boring the block here. Boring the block IS a minimal gain across the board. BUT there are advantages to a larger bore, primarily in the flow gains with the proper combustion chamber work. You'd be surprised what an extra mm of clearance will do on the intake, especially one designed to flow sideways into the cylinder. IF you want easy gains stroke it. Stroking the 22R does require a bit of tuning beyond what can be done stock fuel systems. Done right it'll last as long as a stocker, especially at the RPM ranges used in crawlers. Do your homework on that one. Either way you look at it, the only way to get more out of any engine is efficiency. More efficient intake and exhaust. More efficient combustion. Less friction. Proper tuning. You can go with an engine builder with experience, probably best, or do it yourself, research research research. Know what you want before you start, find out what you need to get it, and then look at your bank account cherishingly as it's going bye bye. It is definitely true that a swap will have the best bang for the buck though, unless you're like me and don't care about best bang and insist on doing what you can with what was provided, y'know, I'm keeping the 22RE and no, I'm not super or turbocharging the thing.
Toyota has already proven the 22RE can be tuned for 140lbtq and 115hp. With a little tweaking and bolt-ons you can get another 10-20 lbft/hp. With another $3k you can get another 10-30 lbft/hp easy enough. The 22R really isn't a 'tuners' engine by any stretch of the imagination and all the stories your hear about big numbers, 200+ anything takes a lot of experience and even more money to get it.

Take any and all advise with a grain of salt. 1mm oversize valves don't do anything spectacular without the corresponding port work and grind. A 'new head' can be worse than a rebuilt stocker if the designer sucks. Aftermarket pistons are a turkey shoot. Machine shops are probably your biggest worry, a bad shop can destroy all your research and expensive parts for a lot of money. And of course, if all is done perfectly and the tuning isn't right your engine can put out less than stock.

Best to your build! Have fun doing it!

2 times that!!   

Pistons.
Cast pistons are inexpensive, can handle the pressures and heat cycles that are typical to our stock to medium tuned 22Rs, but these are where the iffy section is. The alloying process and the foundry processes make huge differences in the quality.
Hypereutectic pistons are great pieces. Just keep in mind the addition of silica to the aluminum create an insulating effect in the metal so the heat stays in the piston. The HE alloy tends to reduce the expansion characteristics of aluminum allowing really tight clearances to the cylinder wall, The heat retention does raise the heat in the piston rings necessitating an increase in the ring end gaps. Pretty much all of the failures I've seen with KB hyper pistons was from ring seizure. All it takes is a hard run up a hill or a little overheating in the engine to close up the gap enough to need a tow truck. Look into the recommendations on increasing the end gap by intended use.
Forged pistons.
Really can't be beat, if your budget allows. There are several alloys available, choose the one that best suits your application. I'm not recalling the alloys right now, but if your app. is for daily or frequent use avoid the alloys that have the greatest cold clearances, they're noisy, even when heated up. The loose clearances also tend to accelerate cylinder wall and ring wear.
Rings.
My suggestion for a long life is to go for the thicker rings. The thin rings will require a rering in half the time. Thinner rings have less friction that will result in better output and economy. If you think 5lbs of torque and 2 miles per gallon are worth the shorter time to opening up your engine are worth it in your application then that's the way to go. For longevity go with rings that have more meat on them. I like to use Deeves rings, sweedish steel rings that are more flexible than the typical rings you'll find everywhere. I've found them to be thinner than regular rings with lower tension while still having a longer life than other thin rings. Zero gap rings offered up by Total Seal and Childs and Alberts are a good investment as they keep the gasses in the cylinder and out of the crankcase which increases cylinder pressure improving output and economy while reducing emissions and oil contamination as well. Reduced oil contamination can increase engine life too.

Bearings.
Look at the bearing builds. A manufacturer that makes bearings for a V8 engine (Clevite) knows how to build a bearing for a brute engine. Pretty sure you won't see the same bearings in an Indy car. Definitely be sure to get bearings with a soft break in layer. Also consider the oil you would like to use, bearing make-up will vary from one oil type to the other.

Head.
Rebuilding the old head may be better than getting a new head, especially if it's not been done before. Either way, old or new, I always install bronze guides and get a good lotta angle valve grind. If you plan to go with bigger valves, don't do it without corresponding port work. Just installing bigger valves can hurt flow. If you want better flow numbers and better charge characteristics in the cylinder have the combustion chamber worked. There is quite a bit to be gained unshrouding the intake valve.
The piston head clearance should be at least .025", no closer than that, unless you want to do it all over again. Best would be .030" no more than .040".

It doesn't.
True.
The moment of inertia is more complicated than that because it depends on the shape of the spinning object as well as its mass.
As I said before these discussions are much clearer when everyone involved uses the correct terminology  for the correct concepts.

The last thing I have to say in this debate, which others have already said:
A heavier flywheel (Actually a flywheel with greater moment of inertia) stores more energy at a given RPM than a lighter one. This extra energy can be used to help your engine keep spinning between cylinders firing at 200 RPM, or it can help your rock crawler tire climb over a bigger bump. These are good and worthwhile things but do not mean that the flywheel added any torque, just more stored energy in reserve. Like having more money in your savings account without changing your monthly income.

I hope some of this is informative. Have a nice day everyone!

Sorry Lewis...  you are wrong and your "physics police" badge is bogus.

The measured force is TORQUE which is a real, indisputable measurement of the actual force - inertia- created by a rotating mass with a given radius from its perpendicular location - axis of rotation - the end of the crankshaft.  A 30 pound flywheel will produce more measurable torque than a 10 pound flywheel with the same radius and spinning at the same RPMs... it's simple physics.

The moment of inertia is the rotational mass and the torque is rotational force.

Here... I'll make it real simple for you....  here's handy calculator.  You plug in your numbers and see if FORCE changes and if FORCE can be calculated as TORQUE:

https://www.omnicalculator.com/physics/centrifugal-force

Gnarls.

Alright guys, you're mixing apples and oranges here. .... A flywheel neither increases nor decreases an engines output.

S…..  I see your point.

We’re not talking about apples and oranges, we’re talking about the laws of physics, and specifically a rotating mass, inertia, and centrifigal force.

Would you agree that the engine creates inertia in the flywheel?

Is inertia a force?

If the engine stalls at 550 RPM while climbing a steep rock with a 10 pound flywheel, why does the engine stall at 250 RPMs with a 30 pound flywheel?

What is the stored energy, or force, or whatever you want to call it that is being applied to the input shaft of the transmission while climbing the rock as the engine stalls at 250 RPMs?

In the science of physics, what is that force called?

Gnarls.