iOnic wrote:Mr Revhead wrote:While there maybe some samness in some angles etc there is bugger all else the same between the 4AGE and BDA.
Yeah aside from bore, stroke, porting, valve sizing, power output and ancillary placements - they have bugger all else in common. But that's a whole other topic on it's own.
Actually, bore, stroke, porting, valve sizing, power output and ancillary placement are all different.
I gather we're talking of the Atlantic spec BDA?
Bore is 80.962 4age is 81mm
Stroke is 77.6 4age is 77mm
cc is 1599 (Atlantic spec) 4age is 1587
Inlet Valve is 31mm 4age is 29.5
Bore spacing is different. None of the manifolds will line up.
Porting was to suit the bigger valves. Other than the general look none of the dimensions match.
Power, BDA was a racing engine of varying sizes and tune. Power output varies accordingly. I'm sure you'll find a spec to match the 4age. However in Atlantic racing the 4age retired the BDA.
Ancillaries, BDA is based on the Cortina block, has the dizzy in the block. 4age, cam driven off the head. Other accessories were mounted either Cortina style or off custom mounts for custom racing applications. Again I'm sure you can find a mount similar to the 4age.
In addition, bore spacing, deck height, rod length, valve angle, almost everything other than general layout is different between the 4age and the BDA.
The issue with the BDA is that it's not a single point of comparison. It's a wildly varying racing engine from 785cc to 2137cc. I'm sure you can find similarites between it and almost any engine of the same basic DOHC layout.
By the way.... FT-86... FUGLY in my books. Still I'm not a fan of most modern styling. 350Z, GTR, RX8, all FUGLY. Give me a Batman or a ST205 anyday.