1994 FZR600R engine transplant

[plodder]

What are the firing orders for each of the engines?

[Evilchicken0]

Because FZR's all have two coils they fire fire top and bottom dead centers so the real firing sequece is 1+4, 2+3, 1+4, 2+3 .... and that's usually the same on every four stoke IL4. The cylinders fire (as in explode) on the the top dead center of the compression stroke thats usually 1, 3, 4, 2 in order to balace the engine ... vibrations are caused by the 3 to 4 and 2 to 1 fireing order which is where the honda V4 comes out smoother.

What I think happens with the 400 > 600 loom is the wires into the CDI are in different places in the block connector or they change further up the loom.

[plodder]

I understand the wasted spark thing but got the impression from the previous post that the 600 and 400 had different firing order, so would need a rejig of the coil wiring but that doesn't sound like what you're syaing.

I was thinking just use the 400's CDI, loom and coils. With the 12500 limit imposed by the speedo restrictor being removed then the limiter is 12.5K as opposed to 11.5K but as long as it runs it then it's somewhere to start from.

What are the pod filters like as I don't want to be cutting up my 400 airbox or my tank?

If this job isn't as straightforward as I had hoped, I may sell this 600 engine on and just thrash it as a 400

[Evilchicken0]

Ask FZRtim how he sorted his out.
I don't know about changing the wires to the coils. It follows they fire in either 1 or 2 position as do the cylinders, if you know the firing order you can simply change the HT leads to suit. To find the firing order take the plugs out, and poke a long thin stick down the hole of No1 hand crank the engine until the stick is high and the marks shown TDC top dead center. Now find the corresponding cylinder (probably 4) which should be the lowest. The HT leads from one ciol go on these ... if it doesn't fire but you get a backfire ... it's the wrong coil.



Probably.

[fzrtim]

Sorry if i have caused confusion by saying firing order, I think the firing order is the same but the timing is different. Also the plugs on the 600 cdi are totally different to the 400 and cant just be plugged straight in. I had to chop and swap the plugs from each loom to graft the 600 into the 400 loom.

[plodder]

But my point is how different is the timing? I've looked up the 3TJ and it's 37°@3500rpm, whereas my FZR1000 EXUP is 40°@5500rpm. (I have a curve for that and it says 33°@3500rpm). The curve is also different for different countries, which I assume is either an emissions or restriction thing. Unfortunately I have not yet sourced a curve for the FZR600R

If the pickups are the same or can be swapped then I see no reason why the whole unadulterated 3TJ loom cannot be used to run the 600 motor?