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Premium Member
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Discussion Starter #1
I have just had my 89 spider veloci engine overhauled.the guy that did this told me he has done many of these upgrades ,he used 10:5 pistons,bigger cams new distributor and coil,headers and exhaust,and duel webers.
After a little messing around I think I finally have this thing dialed in.My question is, we used the original 2L block with a spica head.going by the manual the initial timing should be set at 11*
(Some say thats to much initial timing) but it seems to run and start great at this setting,so do you go by the manufactures timing based on the engine block or do you use the timing that would be correct for the spica head,which I have no idea what vehicle the spica head came out of so I don't even know how to find the timing specs.for that head.
Do I time it based on the block or the head?
 

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Premium Member
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Hi there, hope it's a fun car for you. I'm a bit lost on where the 11* comes from but let's give it a shot anyway. Need some more info. You say bigger cams, new distributor. Do you know exactly what cams, is it a new electronic distributor like 123 or something? I can't see anyone putting a new points distributor in these days. I don't believe there is a mark anywhere on the engine that is 11*. Ignition timing, if electronic distributor, since the car is already running then the rule of thumb is to set max advance at the M mark on the front pulley at 5000 rpm and where ever idle timing falls, that's just where it is. You say it starts great, so that's good.
Cam timing, you would be advised to find the old shankle cam timing templates online, print them off scaled correctly and glue them on something stiff and thin. Then you can use those to see what your front cam cap marks are and then likely make changes to those. Make sure you have a couple new lock tabs on hand for the front nut before you start changing timing. Depending on what cam you have will depend on where it wants to be timed. There is way more experience on here than me about cam timing so hunt those threads out, alfaparticle, Alfar7. These two also have lots of info on here about Weber tuning, which I'm thinking is where you are likely going to be spending the most time as there is no baseline setup for your engine. You will need to know what model Weber. Should be a fun path getting it all correct.

Cheers,
 

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Richard Jemison
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7,183 Posts
Ign timing

"Initial" ign timing is dependent on the distributor`s total advance.
The critical timing is the max advance at 4000 RPM up.
Typically the 2 liter with higher compression (above 10 to 1) responds maximally between 32 degrees max advance and 34 degrees max advance.
Set the distributor for that max advance and see what you have for "initial" advance. Older distributors often have an issue with returning the "flyweights" controlling the advance to the rest stops due to weakened springs and friction, leaving idle RPMs high, & that is the indicator of that problem . If the timing seems to drop very slowly or not at all, but can be brought down by a little load on the engine and the idle continue smoothly at the low rpm, then you need to address that issue.

Some of the Bosch & Marelli (inc. Plex) have too much advance range and at too low a RPM point where advance starts. With those setting max advance for your 2 liter commonly results in too little advance at idle and a dying engine as a result.

After Ed`s (alfaparticle) extensive test with the 123 distributor, most "performance builds" work extremlty well using the "D" curve.
It has (from memory) a total advance range of 20 or 21 crankshaft degrees, starting at about 1100 RPM. So if set at 32 degrees max it will drop to 10 or 11 degrees initial advance. setting your idle speed to whatever you want it to be will(Should...) result in a stable & responsive "acceleration" off idle.
If off idle is hesitant then likely initial advance is too little/low.
 

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Agree regarding cam templates. Timing marks varied through the years. I suggest that you start with a "safe" 104/104 timing. Then read about checking piston to valve clearance and see if you can move to 101 intake and 107 exhaust.

Setting ignition timing depends upon what kind of distributor you are using. 5 to 10 degrees of static advance should get you started but max advance is more important. I would set that to 34 degrees BTDC provided you run on premium fuel. Use at "P" mark on the pulley and verify that it is lined up with the pointer at TDC, then use a variable timing light. If you want to use a simple fixed timing light then make a max advance timing mark on your pulley. d = pi * D * 34/360 where d is distance from P mark, D is diameter of pulley.
 

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Discussion Starter #5
thank you guys for the info, I will check this out and see what happens.I am going to get a 123 distributor and play with that.I can't wait.
 
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