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Discussion Starter #1
In parallel to building my Alfa 1600 engine I am working on another project which had run out of steam for various reasons, but not least as I couldn't finalise decisions regards the cam grind.
In short, the question is whether learning about effective modern profiles for Alfa's can be directly transferred to another "seemingly" similar engine?

I have a Daimler V8 2.5 Ltr which has been bored +52 for high comp pistons and stroked +75.
This Turner engine is basically four pushrod Triumph T140 Bonneville's blocked together; and the heads have been ported by an expert in Triumphs with larger valves etc.
Higher comp Bonneville pistons fitted to lift the CR to around 10 from 8.2.

The head construction of the Daimler appears very similar to my 1600 head (and likely more so to the 1300?) although with offset plug.

Values are: (my 1600 in brackets or JK target)

V8 Modified:
CC per cylinder: 347 (392)
Inlet Valve : 40mm (42.5 =+1)
Exh Valve: 38mm (37)
Inlet throat: 36mm (39 JK)
Exh throat: 34mm (33 JK)

Redline RPM as standard on the V8 was 6300 (Bonneville 6500)

Stock cam duration was 258 deg and 111 deg lobe separation. Max torque at 3000 rpm. This engine built to handle a 3 speed auto smoothly hence these specs; my car is a 4 speed manual with O/D.

The idea here is to create a torque engine and not a high speed HP unit so the redline appears no constriction.
Do some of the more recent Alfa profiles with similar duration but higher lift throughout form the basis of something which could be copied over (Intake and Exhaust combined with tightened LSA) to the V8 with some degree of certainty?

nb. Cost of billet cams for the V8 is prohibitive due to their distributor gear design and likewise 'experimentation'.
Am looking for 10mm lift (vs 7.5 stock) which i know entails work to the tappet check not least to stop them rotating in bores.

Any thoughts welcome!

thanks

Jim

V8 Head
Dv8.jpg
 

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For a similar engine, rpm range, and combustion chamber, sure, cams are cams. My MGA Twin Cam had a Kawasaki grind recommended by MegaCycles. Ran better than the stock one. Cam design has come a long way since these cars were built.
Good luck, my dad had an SP250 when I was a kid. Super interesting car.
Andrew
 

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Discussion Starter #4
Flat tappets have to rotate in their bores.
Ah yes...sloppy language.
I meant rotate out of their guides at longer travel with a higher lift cam.....although the chest has been in the shed so long maybe I'm making that up!
 
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