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If you are not 100% sure, do not answer this question(not trying to be a dick but need the RIGHT answer)

ok, so most of you know im doing the major build on my 02 R6, engine and cosmetic...


I'm no newb to building/rebuilding engine's but this is my first "small" engine rebuild. I finally got my parts to get my engine going back together and heres my question

Since i have the head off the bottem end, how would i tell on this engine when it would be the compression stroke so i can get set for TDC?? I dont want to end up 180 out on this and have to redo it all...
 

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If you remove the oil pump cover (and be careful not to remove the timing chain guide dowel when you do that), there is the pickup wheel. It should be a 4 tooth design w/ one of the teeth alot thicker than the other 3. Either that or its a 4+1 design, meaning 4 teeth spaced 90 degrees apart, and one extra tooth thrown in for good measure. That one extra tooth or the long tooth will mark TDC on the piston. When its perfectly aligned w/ the pickup, you should be at top dead center. At that point, you should be able to install the head and make sure the cam notches are lined up correctly and you're good to go. You can't get these engine 180 degrees out like cars because they fire using wasted spark ignition systems. Meaning that both cylinder 1 and 4 (and 2 &3) fire simutaneously, even though one is in its compression stroke and the other in its exhaust stroke. You just don't get any power out of the one that isn't in its compression stroke.

I'm not explaining this well, sorry. But basically as long as cylinders 1 and 4 are TDC, and you mark up the hash marks on the cams, it will run correctly. If you put the cams in 180 degrees out of wack, when you think cylinder 1 is firing, cylinder 4 will fire. It should still run fine though because its carbed and only a sequential firing fuel injection system would be messed up. Even then, it would still run, but it would be down on power.
 

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Thx agent, thats what i was thinking, wasn't 100% sure tho so i went with my gut judgement and started the job.

My intake cam is perfectly lined up but the exhaust cam is being a lil bitch, its prolly 10-15* out of sync so im working with that at the moment. These lil cam chains aren't my fav thing right now.

but, i do have my motor right here beside the comp in the house so thats 1 + to doing it now...lol
 

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AWDXTCY said:
Thx agent, thats what i was thinking, wasn't 100% sure tho so i went with my gut judgement and started the job.

My intake cam is perfectly lined up but the exhaust cam is being a lil bitch, its prolly 10-15* out of sync so im working with that at the moment. These lil cam chains aren't my fav thing right now.

but, i do have my motor right here beside the comp in the house so thats 1 + to doing it now...lol
Yea just make sure you get that exhuast lined up perfectly. buddy had to do some head work on an 02 and when he lined up the timing he said the exhiast cam's marker was maybe a mm or so off the marker on the tier. Well needless to say he ended up with 4 horribly bent exhuast valves. I believe he said once he got it all back together that the main reason he couldn't get it to line up right from TDC was something to do with cam chain tensioner. So you may ask agent or search around. If the guy was still alive I would call and ask what it was he had to do the second time to line it up right.
 
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