I currently have a A15 in my 1200 sedan with a 25/65 cam running a 32/36 webber. I like the torque but i love to rev the crap out of it but there is no point as the torque band stops pulling after about 5500-6000 rpm.
I would like to know would the a14 be a better option as it revs very similar to the a12, get the thing reving to about 8000-9000rpm with a big cam etc or what can i do with the a15?

The other thing i have read on this site is to put the A14 crank into the standard a12(dizzy at front) little bit of work to fit it, use 120y conrods and use a15 pistons. I think the engine volume was something like 1435cc's sounds very tempting.

I just love revs and the a series sounds great when its reving like the clappers but is it worth it in power output verses torque.

Cheers, Anthony

It's not worth it unless you are racing, high revs will wear the engine quickly.

The A15 will rev up very nicely, you just need more cam, better exhaust (use headers/extractors) and a bigger manifold. Also of course stronger valve springs.


8000 rpm A15

go for more torque..............

A wide torque band is the best ,, if you can acheive that you will make the car very driveable which means you dont need to down change the gears as often and short shift on the up shifts ..if you desire .. But Maximum acceleration is at maximum torque ... Horsepower sells Cars .. Torque wins races !

Quote:
If you use the 120Y rods, you will need to have the wrist pin hole increased in diameter to accomodate the pins in the A15 pistons.
These rods seem to have a little more meat in this area than the 1200 rosds, or at least the ones that i have are.
In all fairness, i bored out my 1200 rods when i used A14 pistons in my 1200 engine. They have seen two sets of pistons & two full service lives without problem, so any A12 rod would be useable i guess.

You will get 1434cc if you use a 77mm bore, which is the second oversize on the A15 bore size. If you use a later A12, you should have no dificulty at all with the 76mm pistons which is the stock A15 size. I will need to go to this size as my bore is already 76.5mm, & it's worn.

after reading all the data you gave me on this dodgeman, thie engine will have the goods but some of the machining costs start to ad up when looking at having it done professionally. Unless you trust the machinist and are competent at building this engine yourself or have a person that can do it for nothing or almost nothing in their spare time...... id be happy with a strong a15 as this peson already has, just do the valve springs, twin carbies and work with the already highly desirable package that it sounds like you have there, less costs and also measurable performance increases for you.

Still i am collecting these parts still for the a12 big block... a14 crank is the killer.

I checked some replacement A14 pistons against the used A15 one that was laying around. It looks like the only diference between them is in the top. I had thought that the skirt & the boss below the pin of the A15 piston had been shortened to accomodate the A15 crank, but it looks like it isn't.

The underside of the piston seems to be the same below the wrist pin & in the skirt. If you machine about 100 thou, or 2.5mm from the top of an A14 piston, you will have a flat top piston of 76mm [or larger] that will work in a stroked A12.

This machining will remove the ring that forms the rim of the bowl, so only a relatively small amount would come from the floor of the bowl. I think that we have some second oversize A14 pistons in stock, so i thought about using these instead of the A15 ones, but the compression would likely be so high that running on Methanol [alky] might be a proposition.
I gave the idea a miss. I want something in the 9.25, up to about 10 to 1 compression range as fuel that i can buy anywhere is usually happy with that.

The things you learn by looking.