Quote:I don't remember the source but I seem to recall that the A10 cam had a few thou more lift than a 1200 cam, but that's all that there was in it, a few thou.

All A10 engines use the same cam, so a coupe one won't offer any advantage.
Remember that these single carb cams are designed for 'relatively' low engine speeds to allow little old ladies to tootle around high density urban areas at low speeds, so a stock A10 or 1200 cam should be fine in a blown engine, at least untill you get the bugs sorted.

EDIT

OK, OK, here's the goods on cam timing from my factory go-fast manual.

ONE CARB, Std CAM. Part No. 13001 - H1000 [stock 1200 cam]
Working angle. 248 degrees.
Intake opens 14 deg. BTDC
Intake closes 54 deg. ABDC
Exhaust opens 56 deg. BBDC
Exhaust closes 12 deg. ATDC
Overlap 26 deg.
Valve lift 8mm
Valve clearance when checking 0.35mm

[remember these figures are measured at the valve]
Lobe separation is not mentioned but you should be able to figure out what it is if you do some maths. It's late & I'm too tired

I also have details for the GX cam as well as three factory optional race cams if required.
I hope that this is of some help.

Sure it'll go good with a supercharger. I dunno if it is the "optimum" cam profile, but it'll work fine.

Regarding the Datsun 1200 camshaft compared to Datsun 1000:
Quote:
Sounds like they just modified the ramps. But maybe the duration is substantially different.

All the factory cam specs (except A10) are listed in Camshaft

The difference could be in the carb and exhaust rather than the camshaft grind?
I do notice the coupe engine to be more spritely up high than the standard b10
with less torque than what little old ladies would like in the kb10.
The coupe seems to enjoy the freeway cruising and overtaking over the stock a10.

I cant work out the lobe sep so will await when you have some time if possible?

The KB10 engine makes more horsepower. For one thing, it has a GX-like twin-outlet cast iron header (exhaust manifold).

Its got teeny outlets compared to a gx but helps with revvs up high thats for sure

just going back to what Chris said about the rods having a 4mm difference to the a12
that would mean the conrods of the a12 are 121.5mm - 4mm = 117.5mm ???
I always thought A10 had 119mm rods ???

Rods
•12100-H1000 A12 CONNECTING ROD 121.5mm/4.78" center-to-center
•12100-18500 A12A CONNECTING ROD 121.5mm/4.78" center-to-center
•12100-16200 [1974] A13 CONNECTING ROD 133mm/5.24" center-to-center
•12100-17200 A14/A15 CONNECTING ROD 133mm/5.24" center-to-center

117.5mm then? Chris will know for sure.

Would like to use the a12a rod but then Im limited to a flat top
piston which will need a slightly bigger chamber a a shim or some
serious swirl to stop detonation at 10psi.
Motorbikes like cbr1100xx run 12:1 comp with 10psi and get away with it
but an A10 will need a swirl head we never got here.
Although very restrictive for power going from an a14 to a10 would be grand.

Ok fellas I found on my datsun 1000/1200 manual finally
that the Datsun A10 conrods measurements are:

116.97mm - 117.3mm so thats one for the Wiki

however camshaft specs none for a10 b10 or kb10

So A10 Conrods are about 4mm shorter than A12. That fits in with what the Datsun service bulletin says:
Quote:

A bit late as usual, but here goes.

The engine in the KB10 differs from the A10 engines in other models in the following areas & this is gleaned from my parts book.

Cylinder head. Half a point more compression. Pistons are the same but the head has a different part number for the KB10.

Exhaust manifold. Dual outlet design but with provision for stock, single carb inlet manifold heating. Just the ticket for a 'stock' 1200 engine & as a bonus it has no flapper valve shaft to leak & make noise.

Distributor. Different cam for the points & different advance curve.

Carb. Different sub model with different jetting.

This added up to an additional 4hp at something like 6,000 rpm. It should be noted that the coupe is the heaviest in the B10 range so this was possibly done to allow it to keep up with the others LOL.