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Discussion Starter #1 (Edited)
For reasons I can't recall I ended up with one euro 10548 cam and installed it on the intake side of my rebuilt 2 liter head which has yet to be mated to the block. Is it worth sourcing and installing one on the exhaust side, or will it play nice with the stock USA cam I presently have installed on the exhaust side?

Edit - browsing this forum I just came across this from RJ:
http://www.alfabb.com/bb/forums/engine-rebuilding/398361-can-i-swap-camshafts.html#post6111753

Seems like I have a good setup. Maybe I knew what I was doing after all?
 

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If you have one Euro and one stock US then the Euro should be on the intake and the US on the exhaust. RJ may suggest optimum lobe centers if you ask him.
 

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I have a 1750 in my 71 Spider that has been converted from SPICA to a full Euro Intake Weber set-up. While my engine was being rebuilt, I asked my Mechanic, who is an Alfa Specialist (Home) to install some mild cams - I wasn't looking for a performance engine; just a better match for the Webers and a little more zip.
He chose a 10548 - intake only- as the best set-up.

The engine is very sweet and smooth - but I made so many changes at the same time (rebuild, euro intake, 123 distributor, rejetted carbs) that it would hard to quantify any performance improvement and attribute it solely to the cam.
 

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Discussion Starter #4
Thanks guys. I titled my post wrong but got it right in the body... I have the 10548 on my INTAKE and stock USA on the EXHAUST. So it sounds like I have the right setup for a mild bump in performance.
 

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What valve timing - lobe centers have you set them to?
 

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Discussion Starter #6
I don't have them set up yet - I just have the cams set to their marks so I can install the head at TDC, which I hope to do later this week.

Any suggestions?
 

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What year is the head? The timing marks varied quite a bit during the 70's. Alfar7 can give you better advice than I, but 104/104 should be close to optimum.
 

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Discussion Starter #8
What year is the head? The timing marks varied quite a bit during the 70's. Alfar7 can give you better advice than I, but 104/104 should be close to optimum.
Presuming the head was never swapped, its 1973. I'll get in touch with RJ if he doesn't post here...
Thanks
 

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1973 timing was 114 intake and 102 exhaust. You should download the cam timing templates from Centerline. The intake mark needs moving for sure.
 

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Richard Jemison
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Cams

104/104 is fine.
However its smart to turn the crank a few degrees to get the pistons below the lop of the liners and roll it back to TDC after thead is torqued down, then install the chain and time the cams.
 

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Discussion Starter #12
Is printing out the template and remarking the cap the best way to set the cam angles? What is the professional way of doing this?
 

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Is printing out the template and remarking the cap the best way to set the cam angles?
As Quadrifolio posted a degree wheel is the most accurate but the cam templates are good enough for the cams you are using. The resolution of the vernier adjustment of the cam timing is 1.5 degrees and you can get that close with the templates if you are careful.
 

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105480320051 Cams

I think my post got lost somewhere. What is a 105.48.03.200.51 camshaft? They are installed in my Spica HP - Alfetta. Measured lift is about 10.55mm. Does anyone know the rest of the specs? (The numbers are all cast, not stamped.) Thanks.

Mr. Goose
 

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Some info about your "mystery" cam on RJ'S website ; it is some sort of Euro original equipment cam.

quadrifoglio says you need a degree wheel and an accurate TDC mark. The latter part is fun. Alfa provides a TDC mark on the crank pulley and a stamped steel pointer attached to the water pump. Th pointer can be easily bent a few degrees one way or another.

It is possible to retrieve the true TDC indication by using a dial gage on no. 1 (or 4 if you really must) piston. But wait; turning the crank back and forth to try to establish TDC will get you nowhere for two reasons:
- the piston motion around TDC is infinitesimal
- as you move the crank backwards the backlash in the lower chain will defeat what you are trying to achieve.

I attach a degree tape (can be printed from an excel file, adjusted in length to correspond to the pulley's circumference) to the lower pulley. The trick is to adjust the pointer such that 30 degrees BEFORE TDC gives the same dial gage reading as 30 degrees AFTER TDC, always rotating the crank forward. A bit tedious, easier done when the head is off.
 

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105480320051 Cams

Thanks, ALFAPARTICLE. I read all those posts from 2008... wow! I'm going to pull the cams and run them on my homemade "degree machine". (Haven't used it in years, but I could draw very nice and accurate graphs from it.)

It sounds like Alfa could have ground different pr0files on the slug marked 105480320051. (On my cams those numbers are all cast, not stamped later.) One person says the lift is 10mm and the other says it's 11mm. Well, using pretty good electronic calipers on 8 lobes my lifts averaged out to be 10.55mm. So, I want to run a complete profile to see what my .51 cams really are.

For the record, they were purchased in 1985 from A.F.R.A., and the buyer (previous car owner) requested GP1 cams... I have the original paperwork on that. The engine runs good, but I am just scoping out what I have, to see if everything's set correctly. So far I've discovered the lobe clearances are all set way too tight, scary tight!

Mr. Goose
 

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It is a common misconception that you can gain power by tightening up on the tappet clearances. Every cam was designed for a specific clearance and you will most likely lose power by changing it.

The minimum adjustment of the cam timing is 1.5 degrees of crankshaft rotation -that is one hole on the cam flange. I firmly believe that you can achieve that accuracy using the simple templates that are on the Centerline site. I determine TDC with a dial gauge that fits inside a spark plug housing. It is simple to use and inexpensive to make. I posted pictures of it in another thread. You should be able to find it with a search.
 
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