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Discussion Starter · #1 ·
I've buzzed through numerous interesting threads after searching for "flywheel" but I find no answer to this simple question.
I ask, how many teeth are on the starter ring on the 1.9 flywheel?
One of you would certainly have this number in his head, others may have a flywheel totally visible and could please very carefully and accurately count the teeth for me?
I want to re-degree my cam, I know it isn't quite right, but my degree wheel won't fit with the engine in the car. :(
So I think maybe I can figure out how to use the ring teeth as a degree wheel...
Sounds almost logical, eh? As our Canadian friends would say.
Thanks guys, should this work I promise to share the procedure! :)
 

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Old Opeler
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Dang!

Jeff, You come up with some brilliant ideas - and a tricky question from time to time - no info in any of the many manuals I have so it is going to have to be a manual count - my nearest flywheel is 8.2 kms away .......
 

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OPEL-LESS!!!
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both the felxplates and flywheels have same number of teeth, the starters can be switched back and forth between one with manual trans and automatic trans.
 

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Old Opeler
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By the Tooth!

Just on 2 1/2 degrees per tooth ( 2.535 degrees) - close enough to 2.5 for a range of four or five teeth! With the starter motor off there will be enough teeth visible to use a pointer and move the flywheel (manual or auto ..) around 2.5 degrees at a time.
5 degrees initial advance - rotate back from TDC (determined by the ball in the flywheel) by two teeth! 35.5 degrees total advance - 14 teeth!
 

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Discussion Starter · #8 ·
Thank you, Jordan!
Baz, the degree wheel is hard to use with the engine in the car, I'm going to come up with a really really simple way to use the flywheel which is extremely visible under the car with the bellhousing shield off.
Righto, Jim.
Using Jordan's tooth count and some math (all fingers and both shoes off usually, but I cheated and used a calculator) I find that my cam (Isky # 625177) should lift an intake tappet .020 at 12-1/2 teeth before top dead center, an exhaust tappet would be up .020 at 28-1/2 teeth before bottom dead center.
How incredibly simple.
I know my timing isn't right for reasons we've gone over before, plus I goofed by letting the difficulty favor the advanced side, a good tip for street rods but not good for high rpm power. My mistake was simply backwards...
Tonight I'll continue work on getting more front wheel camber, last night I got the right side maxed out way beyond any stock adjusment possible, next we pull some covers, mark some flywheel teeth, and play with a dial indicator...
I'll share the results in this thread when finished. Thanks again, guys! :)
 

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Discussion Starter · #9 · (Edited)
Baz, can you change the title of this thread to match the title of this post, now that it isn't so much about teeth as it is cam timing? Plus I started it all in the wrong forum, we're tinkering with cams, not pedals... Sorry about that, but we're all making you work for your supper :D Thanks!
I got an early start tonight, skipped the camber project for now and dug into my experiment with degreeing. Pictures below will help keep this clear. It is so simple I can't believe it hadn't been thought of before...
You do not need a degree wheel.
Step one, put the timing ball on the pointer. I'll show you a trick for this in a minute, but once the marks are on, pull your tin cover off the bellhousing.
My flywheel is painted silver, helps you see it! With a straight edge and a Sharpie make a line on the flywheel as long as you can, trying to estimate crossing the center of the crank and continue this line outward, across the ring gear teeth, across the gap, and across the machined face of the bellhousing. This is shown in the first picture, we are under the car looking up on the left side of the engine. This mark is TDC, top dead center.
Then, I started counting teeth, marking every fifth one with a 5, 10, 15, 20, etc, rotating the crank a bit to keep going. At tooth 71 I made a big mark, call it BDC (bottom dead center). Keep going, till #140 and notice you have two teeth left before TDC. Notice this in the second picture, the teeth are numbered to help you keep track of where you are, and notice the big orange patch. That is the timing ball in the middle of the orange, boy, does that orange help you find the ball in the bellhousing window! Anyway, disregard the orange and the ball entirely in the rest of this operation, it is your tooth numbers and the line on the bellhousing you are using now!
Next photo shows the dial indicator on #1 intake at .020" lift. This is hard to do, the lifter pops up pretty fast. Takes a few practice runs to land this close to .020!
Last shot is of my lovely assistant Joceline somewhat obscuring the marks showing the whole world that my camshaft is exactly one flywheel tooth (2.5 degrees) advanced, or early. Which I knew when I built the engine, and that is with the timing chain a tooth off on the upper gear. See what happens when you mess with milling machines around block decks and head surfaces, especially the head purposely surfaced at an angle?
Were this a street engine I'd call it perfect. Advanced a bit is good for low end power. Now I need to make it retarded, some custom upper gear tinkering is coming next...
I ran through this pretty quick, hope not to have confused anyone, if anybody needs more explanation maybe Gary could help me make a detailed article about it... As we've discussed before, checking your cam timing is a pretty important detail in building any motor. Most people just hit the marks and call it good. That isn't good enough for me! To eat horsemeat for lunch my tiny motor needs to be perfect, as well as very totally textbook legal STOCK! ;)
 

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Old Opeler
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Removes the Doubt

Jeff, Another giant step forward for Opeldom. All the best ideas are simple - after they have been thought of. Now cam timing can be simply checked, removing no more than the rocker cover and flywheel tin sheild. Good one!
 

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Excellent article Jeff, and as GTJIM said, "all the best ideas are simple..." Two Thumbs up. The next engine I pull down will have the flywheel marked before it goes back on. Jarrell
 

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Discussion Starter · #12 ·
Cam Timing Has Been Altered

As we have a weekend off from racing I decided it was time to finally get the cam timing closer to perfect. I started by getting the new timing chain with master link from OGTS, what a deal for only $26 and it was in my mailbox two days later. They are the greatest! I would NEVER AGAIN assemble an Opel engine without THIS chain.
Getting the old one out was simple enough, with the tensioner removed, all valve adjustment backed WAY off, I let the upper gear rest on the timing tab, worked a little flat strap in between the gear and the chain, and then masked off the entire area except for a few links of the chain. The handy dandy 3" cutoff wheel zipped through the chain in twenty seconds! After unmasking and cleaning up the mess I wired the new chain to the old one and started working it in. This took some patience... Meanwhile some mods were made to the upper gear.
Some time ago I made a tool out of an old three bearing camshaft. Cut off the front 1/2" of the bearing journal/gear mounting face. Then pulled out the indexing dowel and started experimenting. I found that when you attach a gear to this tool with the pin holes NOT matching up you get different indexing of the teeth. By drilling the gear using the tool's pin hole as a guide, in both locations, we now have three different settings!
Then I gave #1 intake valve .020" clearance on the base circle and rolled the cam over till the rocker just got tight. Then put the crank on the mark discussed a few posts ago that says "in op" meaning intake open .020.
I put the upper gear on with the pin in a hole other than original, put the chain master link in, tensioner in, and rolled it over two crank rotations, stopping just when the #1 intake rocker got tight again. Looked at the flywheel tooth marks and find the mark is one tooth beyond "in op", meaning the cam is 2-1/2 degrees retarded. Perfect for high RPM power!
But, then the Pocono 500 started and Mikey Waltrip is WAY out front so I can't quite finish adjusting the valves and firing it up yet...
By the way, I had checked lash on all valves before backing them off, all were pretty close to perfect, so my bizarre adjusting nut locking method works well. It works very well, and is easy to use, a 15mm wrench on the bottom nut and a 1/2" wrench on the top nut is all it takes, simultaneously of course...
 

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Discussion Starter · #14 ·
And it even runs!

I got her buttoned up and running, I am pretty sure it has a different sound now. And after coming up to operating temp it will settle into an actual "idle" at about 1000 rpm. Would never do that before! I am anxious to run it around the track in heavy Ford traffic and see if it pulls any harder down the straightaways. Sure hope it quits raining soon. You wouldn't believe how wet it is here.
 

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Hello Jejf
I am sure this is simple but please explain the metal tubes that lead from the camshaft area into the head on pic #3
 

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Old Opeler
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Positive Lubing!

azopelnut said:
Hello Jejf
I am sure this is simple but please explain the metal tubes that lead from the camshaft area into the head on pic #3
Got to be for positive cam bearing lubrication so the oil supply is not dependant upon the easy to block hole up through the head casting .....
 

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boomerang opeler
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GTJIM said:
Got to be for positive cam bearing lubrication so the oil supply is not dependant upon the easy to block hole up through the head casting .....
probably needs it with that poor girls hair stuck in the engine
 

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Discussion Starter · #18 ·
Oh, baz, you are hilarious!!
Yes, in studying the head oiling system and absorbing advice about how to make valvetrain parts work and last longer I came up with the "positive cam bearing lubrication" (thank you, Jim, it had not yet been officially named) because as far as this farm boy is concerned there is just no way in hell that itty bitty oil feed to the head is gonna get it done. We've covered this a few times in other threads about oil drain dams, but I just felt compelled to do something better.
Somewhere is a post about the details of exactly how it is done, it took some doing but it came out nice and as far as I can tell it works. I had the rear lifter out today while tinkering and there is no sign of wear on it, the hourmeter reads seven hours, that would probably be about half "warm up time" and half full throttle 6000+ rpm white knuckle driving time.
The other part of that oiling system is how I drain the oil out of the head, I damn sure don't dump it onto a rotating crankshaft/rod rotating mass! :eek:
 

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Discussion Starter · #20 ·
Funny you should bring this one up. I've been doing a whole lot of degreeing and valve/piston clearancing lately. Still trying to get an engine ready to assemble...
I'm now convinced that when building a very special CIH engine, it is wise to not let the piston manufacturer guesstimate where to put the valve reliefs. Venolia had it WAY off on these ones. Bummer is, they were too far to the right. So we're giving up some compression ratio here. This isn't going to be quite the performer we wanted, but what the heck, it'll run. The next one will be better...
The Isky tools for cutting the notches work well, but the process is very time consuming. Maybe when it's all over I'll write an article about what we're going through.
 
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