Please help!! 1.7 8V twin carb cam profile timing - Alfa Romeo Forum
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Please help!! 1.7 8V twin carb cam profile timing

I have searched high and low, but haven't been able to find the standard cam profiles for the 1.7 8V twin carb motor. The reason I want to know is because I want a basis to go from to choose a high performance street cam.
I've measure (roughly) my lift which is about 10.3 mm, and from what I can see it has roughly, 295 degrees duration.
This leaves me confused as in the 33 cd manual that I have it states the intake timing at 54 BTDC & 84 ABDC, that means its 318 degrees duration!!!! I find this impossible to believe for a standard cam.
I have been looking at 'road max' C&B camshafts, but after doing some research on the standard cam profiles, these cam profiles seem to be a poor choice at best, with only 11.2 mm lift and 280 duration.
I need to find out the specs of the standard cam profiles so I can move on with this project. I've put 16 valve pistons in, which should bring the compression to around 12:1 so I would like to match that compression with a suitable street cam.
Any help would be greatly appreciated.
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Hi bolide, a standard cloverleaf cam is 252 degree and 9mm lift on the inlet side, exhaust is 236 and 10mm lift! These figures are for the 1.5 but am pretty sure the 1.7 is the same or slightly less as some people seem to think. The 252 refers to the actual time the valve is fully open, not the total degrees they'r open. Think thats where your going wrong, i have 296 fast road in my 1.5 and they'r spot on for road use... i had piper 349 race cams in my 1.7 and they'r actually 308 degree and 11.5mm lift and don't come in till after 3k so not ideal for road use... Piper cams can reprofile your standard cams to just about any profile you want and they'll advise you on specs to use for fast road or race... They quote 180 for reprofiling 2 cams plus shipping

Have you put valve pockets in the top of the pistons and or done any other work to them? I'v looked at using 16v pistons in an 8v before but was advised against it as compression is too high without modifying them!

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Thanks sudboy. No, I haven't modified the 16 valve piston as there is no fear that there will be piston to valve contact. Simple reason being that the standard pistons are deep dished in the centre with a flat part all around the outside of the piston which meets flush with the block and also covers a small area where the inlet and exhaust valve open. The 16 valve pistons also have a neutral deck height, only difference being they are relatively flat and do not have a deep dished centre. So to cut a long story short, whatever 'off the shelf' cams they have for the standard motor, will be fine in this setup.
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