Parksy's v4

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Thanks guys. Cogsy, I didn't realise it was fixed that easily. Next time I'll film holding the phone horizontally.

It certainly is that easy *except* there is an 'up' and a 'down' side of your phone you've got to be careful of. If you hold it the wrong way all your pics and videos end up upside down. For an iPhone your home button should be to the right for correct orientation (I'm guessing it's probably the same for other phones).
 
It certainly is that easy *except* there is an 'up' and a 'down' side of your phone you've got to be careful of. If you hold it the wrong way all your pics and videos end up upside down. For an iPhone your home button should be to the right for correct orientation (I'm guessing it's probably the same for other phones).

Haha, glad you mentioned that. Would have saved some frustration later.

Cheers zebdog. I'm really pleased with how it runs. I've definitely got the hang of making IC engines. I need a bigger lathe and mill now so I can make something with more cylinders.
 
G'Day Parksy,
Just fabulous & sounds soooo good mate. I have followed your posts intermittently & you should be very pleased with the result. Congrats on a great build.
Regards,
Don.
 
Does anybody know why I can't see any of Parksy's posted photographs? All I can see is some Photobucket notice. Thanks.
 
Does anybody know why I can't see any of Parksy's posted photographs? All I can see is some Photobucket notice. Thanks.

Photobucket wants us all to pay 400 bucks a year to make our photos show up again. That means we have to pony up the money or move our photos to a new site and relink them to the posts so folks like yourself can see them again. I have thousands of photos posted online so mine will remain that way until there is an automated solution.
 
Photobucket has changed all it's rules, and want people to pay $400 a year to host their photo's. Anybody who doesn't agree to pay, has their pictures blacked out. Apparently there are ways of getting around this and being able to view the pictures anyways, but I am not familiar with how to do this.
 
Is Parksy still around? I'm curious to know a little more about the firing order and valve timing on this V4.
 
Hi rubyfocus, yes still around. Life has been hectic the last year and haven’t been on here as much as I’d like. I’m fairly certain the firing order information is in this thread somewhere. Valve timing wise, both camshafts are made identical, and I’m also sure the specs are on here. Please let me know if you have issues finding it.
 
Here is what I've gathered so far (I think):

Cylinder numbering is (left to right and left to right) 1,2 and 3,4 the two pairs sharing two crank journals 180 opposed, where the firing order is 1-3-2-4.

#1 fires first (I'll assume that to be 0 degrees), then #3 at 180, #2 at 270, then #4 180 degrees later, which is 450 degrees, then 90 degrees later, back to #1, which is a total of 540 degrees, which falls short of two crank rotations, which is 720 degrees.

If all of this is correct, then I am missing something....

I would have figured that everything is evenly divided by 180 degrees, with 720/4 = 180. But then again, I'm certain that #1 and #4 don't fire simultaneously as would be the case if there was a spark at every 180 degrees. Knowing this then, means that the valve timing is uneven throughout 2 complete crank rotations.

But then of course I'm not even sure if I should be working with two rotations of the crank or one.

So I'm stumped. And from what I could tell there is little discussion in this thread that has been able to definitively solve the mystery. Can anybody offer up some explanation?
 
It's definitely not every 180 degrees. Using your numbering system, #1 at 0 (left bank, front cylinder), #3 at 180 *(left bank, rear), #4 at 270 (right bank, rear cylinder), #2 at 450 (right bank, front) - all as you suggest so far I think - then back to #1 270 degrees later at 720. This makes for the unusual 'beat' of a V4 (and the reason they sound so cool in my opinion).

I think where you made the mistake is assuming there's only 90 degrees of crank rotation between both banks. Going one way there is 90 degrees but going back the other there is 270 degrees because of the direction of crank spin.
 

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