So I understand everyone says that all Honda engines (except K and iirc L series) rotate counter clockwise. But, is this simply because of the orientation of the intake/exhaust ports? Like, for example, does a K series rotate clockwise because it's exhaust ports are on the backside of the engine? I'm confused by this?! I feel as though an engine's rotational direction is described as being clockwise/counter clockwise depending on how it's oriented in the engine bay! Anyway, I'm trying to figure out if the f22b1's crank rotates TOWARDS the exhaust side or the intake side? Thank you all in advance.

 

It also spins counterclockwise.

 

Ok so are you saying YES it rotates towards the exhaust side or NO it does not? Thank you for the reply.

 

Most common FWD engines are located on the right side of the engine bay, but Honda put them on the Left side. Engines usually run the same direction as the forward motion of the wheels.

Being the F/H engines are located on the left side of the engine bay, the engine rotates counter-clockwise, or some say backwards.
If you are looking at an engine you are not quite sure of, the belt/chain tensioneer is usually located on the 'slack' side. The crank will rotate to constantly keep the non slack side in tension. Usually a straight shot between the crank and the cam pulleys or Crank > Cam(s) > Cam(s) > ancillaries.

 

Ok, first, thank you for the reply. And now let me explain where I'm at: so I'm in the process of following ashb82's f22 turbo build using DSM pistons made for an Evo 8. The pistons I'm using are Arias, and in Ash's build log he used wiseco's which he said need to be rotated 180°. BUT his pistons had equal valve reliefs on both sides, mine do not. So what I have found thus far is that overall both engines (f22b1 and 4g63t) rotate in the EXACT same direction, except their belts and pulleys are on opposite ends so one engine is said to rotate clockwise and the other counter-clockwise, but as a whole both cranks turn in the exact same direction! So do I really need to rotate them 180°? It just doesn't seem like the right thing to do? Especially since the intake reliefs are lager!? Idk? But I need to be 100% before I commit and install them into my block, so any input will be hugely appreciated.

 

No. If that were the case then all engines would be considered rotating in the same direction. This is simply not true.

In the 90s Eclipse the 4G63 is indeed on the left side of the engine bay, however it rotates clockwise. The transmissions are four shaft units. There is a separate input shaft from the main shaft, usually these are inline and rotate in the same direction. On the 90s Eclipses this is not the case. Thus you have Input shaft CW, mainshaft CCW, countershaft CW, and differential shaft CCW.

In other words, the 4G63 does NOT rotate the same direction as the Honda F/H engines. Eclipse 4G63 transmissions have an extra shaft in them. I'm guessing with the later EVOs someone built the transmission in a traditional manner(or stuck in another shaft) and the input/main shaft are inline and rotate in the same direction.

You will still need to rotate 4G63 pistons 180° to install them in the F22. This is because piston wrist pins are offest, reason for this is for noise(piston slap) and performnace(piston dwell at TDC). If the piston pin was center of the piston the piston would rock and 'slap' causing unwanted noise. And two is to reduce rod angularity at maximum cylinder pressure, which reduces friction from thrust forces. The slap would be the piston thrusting against the cylinder wall.
Remember, the piston/rod powers the crank. The crank does not power the piston/rod.

To have the offset in the opposite direction would increase stroke, and by definition increase capacity. However this would also make the piston rise higher and piston dwell less at TDC. Ideally, if you can have the piston dwell longer at TDC, it can be used for better flame propagation and power output via increased pressure from combustion.


With that said, I have never had an F22 apart. I do not know if the pistons are offset or if the cylinder bores are. Conventionally, cylinder bores are centered over the crankshaft with the pistons offset to reduce piston slap and increase performance.

Personally I would look at the F22 piston and 4G63 piston, and install the 4G63 piston with the offset in the same direction as the F22, which is most likely 180° from stock for the 4G63.

 

There is no wrist pin offset in the F22 piston. If you have a piston that is offset you want to ensure that it is oriented the same as the engine they came out of. If it is a clockwise rotation then you will have to orient them 180° and fly cut the valve reliefs if the need be.

You can get custom F22 pistons for a couple extra bucks and save the hassle.

 

Thank you Mike, I really needed that clarified for me because it just wasn't making any sense. And you totally hit the nail on the head when you reminded me that the pistons are turning the crank and not vice-versa. lol! So again thank you.

Ghost, I really appreciate your reply. I know you're an f22 guru and I have seen you say on numerous occasions that custom f22 pistons can be had for just a bit more than the cost of the evo's. But I purchased these pistons and rods quite some time ago and am just now getting around to the actual build. To be completely honest this build was in no way planned. I just happened upon the pistons and rods at a price I couldn't pass up and from there the build kind of planned itself! lol! Don't get me wrong I always wanted to do something to upgrade my engine, I just never really seen it being a financial option, until, like I said, these kind of fell into my lap. So here I am. Anyway, again uber-grateful that you chimed in. I've read through your build log on numerous occasions and just LOVE what you've done with the Accord. Ok, so just to be clear, IF there's NO offset in the wrist-pin then I do NOT need to rotate them? Because as far as I can see they're dead center in the middle of the piston, and I don't have top of the line calipers, but they measure up the same on both sides too. Is there something else I should be looking for? Or somewhere specifically that I should measure from, to determine if there's any offset to the wrist-pins? Thank you in advance for any more insight you can provide into this, I really do appreciate it.