I have been reading some of the older stuff on here and a couple months ago you guys were talking about twin cam heads, the subject of Mazda DOHC 16 valve heads was mentioned and i wonder if anyone can tell me more.

I think this would be a great alternative to a transplant.

Could it be done?
Has it been done?
If so, how?
Does anyone know what the HP limits of the standard A series block and bottom end are, along with any potential improvements ?

where in the old stuff was this mentioned? i too would be interested in the posability of a twin cam head, especially for the a14.

I'm yet to get a B6 head to try.
Apparently the bolt hoses for the head bolts are spot on but the rest I don't know yet.
One I find a donor B6 I'll let you all know.

As far as the bottom end is concerned. Ever heard of anyone throwing a rod or breaking a crank ????
I haven't.

i actually do know of an a12 that threw a rod out the side of the block. I will be damned if i know how he did it though.
My mates bought the car with this problem,
took the engine out and also the rod and piston, put the engine back in and drove it back to sydney.
I also know of an a10 breaking a crank, bit with only three main caps who is really suprised?

But in all my experiences i would have to say that the a series is one of the strongest bottom ends around!

Yeah they're strong until you put boost through them. As for Twin cam heads (B6 or BP) one of the clutch guys out my was fiddling with this a couple of years ago, then he got the ####s and brought an EVO 5

poor guy
doesnt know what hes missing out on

I wish I had taken pics. when I worked for a local dealer, we had a B210 come in on a hook with a dead A14. the owner had left it in 1st gear and was towing it behind a motor home at 65 mph. number 2 and 3 rods went through the left side of the block, numbers 1 and 4 were still in place but bent.
taking the time to figure for gear ratios and speed, it was turning about 16,000 rpm before it let go. funny thing was that the oil pan and the cylinder head were not damaged.

Wow, that's a good story.Quote:OK guys, remember to keep your A14 below 15,000 rpm!

I did go so far as to bolt a Mazda B6 head onto a A12 block. While I didn't go any further with the idea I did have an engine builder look at it and he reckoned that the conversion could be done. The head bolted up fine but work needed to be done on matching up oil and water galleries etc. There obviously would be quite a bit of time and $$$ involved but it would certainly be cheaper than some of the other twin cam head options talked about in the earlier forum on this subject.

i know twin cam is better but what is the actual advantage it gives? and this head gives overhead cam, whats the advantage there?