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Discussion Starter #1
A classic theme but need some help... My 2.0L engine probably is fitted with an Alfetta head with mixed parts. My intake camshaft has an inactive variator with part No. 116860320001 and my exhaust one has part No. 105200520000. I had always the impression that my timing was not correct, so decided to recheck. The photo "initial" is my first setup and the "final" is the current one. The marks were existed and it seems that intake is advanced(?) a little bit but in this setup the engine starts noticeably easier, keeping immediately idle even cold and the idle is stabilising 100 rpm higher than initial setup. In a very short drive test engine seems to rev in a more vivid way. Any comments would be really helpful if this OK or not! I have no experience from variator and I am afraid to touch anything on this. My cranck is absolutely in TDC confirmed by a ruler in No. 1 cylinder and coincide with pulley mark.
Thanks!
 

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I would check the marks on the caps with the templates available from Centerline. Then you'll know where your lobe centers are.
 

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Different years and markets had different marks on the cap, so yes, use the CL template or similar to figure out what marks you have there, then time to what you want.
Andrew
 

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Discussion Starter #4
Last (and final) update... Reading numerous post for the same issue I realized that since the variator is not working anymore I shall use the 102 deg. mark and not the 114. Also the cam marks shall be aligned with the outer side line of the cap marks. If I am wrong please correct me... The pictures show the final status while #1 Cyl. is at TDC and chain fully tensioned as it should be. The engine has the optimum operation over the last months (as expected) with corrected timing and the small hezitation in the area 1500-1800 rpm (transition to main jet) almost dissapeared. I am now waiting to test new idle jets so to touch the perfection! 🙂
 

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Richard Jemison
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You are close to where they should be now. But download the Centerlinealfa.com templates and verify that those marks are 102/102.
With the cams where they are now, (predicated on the marks being 102/102) your exhaust is advanced too much. Retard it back to the 102 mark. That will open the exhaust a few degrees later lengthening the power stroke (more HP & Tq.)
\Your intake as well needs to be right on the 102 mark.
But I wonder if your VVT is really not working. Unlike later solenoid activated VVTs the ones used in the Alfettas was centrifugally activated. Unless the VVT had been modified to keep the valve in it from opening to oil pressure which advances the unit (7 degrees) then you might have a problem with piston to valve clearance . Without a VVT working, "For Sure" you could try advancing the intake 1 notch in the VVT (3 crankshaft degrees) which would move your LC from 104(where it appears to be now) to 101 LC which will close the intake sooner reducing reversion and putting more fuel/air into the compression stroke. Again improving power.

First verify that your TDC indicator is really showing the engine at true TDC.
 

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Discussion Starter #6
First of all thank you for the detailed reply! Starting from the end my TDC marker on pulley verified with a ruler inside plug #1 hole, so it's safe and correct. My VVT is the late type with oil pressure thus inactive for sure. I will check my cap marks but engine unfortunately seems to be a combination of different parts... Engine no is falsified so not sure what I have. It's a 2.0 L engine with 105.12 flywheel, Dellorto DHLA40H, blanked the fuel pump base, oil dipstick to the exhaust side but front cover it's not a Spica setup.... My cams are mix, in 116.86xxxxxx and ex 105.20xxxxxxx. Just now I found a pair of 105.48 which is the right one for 2.0 L European engine and I will go ahead with them. Their marks (as per Shankle catalogue) is 99.5° in & ex, so I will redo the whole job again. If any comments would be welcomed!
 

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But Mad North-Northwest
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I asked about this a while back and the recommendation for the 10548s is more like 102/102 or 104/104. Do a search on 10548 and you can probably find more details.
 
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Discussion Starter #8
I asked about this a while back and the recommendation for the 10548s is more like 102/102 or 104/104. Do a search on 10548 and you can probably find more details.
I checked everything that I could find... everywhere is mentioned that factory setup is 99.5/99.5 and some variations where for emissions control, like e 99.5 / I 104 or something close. Other variations seems to be on a test and trial basis. So, think to start from factory setup.
 
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