Thanks for the info on the crank.

I am currently running 34 chokes. Will try 36s before buying 45 Webers. I think the stage 4 cam is only good up to about 7000.

I should know how it compares to other Zs with triple webers as we are having a track day at the end of the month and possibly 9 Zs af varying specifications will be running.

Hi Chris. I think you'll find your engine displacement is closer to 2599 cc.

I strongly suggest that you get your car on a good dyno, and find out what your air/fuel ratios are. It will also give you a chance to dial in the timing.

You may even be fine with 34's.

There is a lot of mis-information out in the world regarding Webers, but the dyno doesn't lie.

Another good idea, IMO, is to get a wide-band O2 sensor with logging ability, and drive with that for awhile. They're not that expensive and are very much worth it.

I now have some answers to questions asked earlier.

Bore is 88.5, Stroke 73.7 Swept cc 453.4 total 2720cc

Compression 10.2 - 1

I have had it on the Dyno and as predicted it is running out of fuel/air just before 7000 rpm

The graph climbs steeply from 5800 but plateaus in the low 6000s and falls away sharply from 6800

The maximum power is a slightly disappointing 176 bhp (Australian draft horses not US ponies!)

Torque is 742 lb at 5100

The next move is to replace the 40 DCOEs with 34 chokes with 45s and 38 chokes. This may have to wait awhile.

In the meantime we are having a weekend club meet at Collie raceway with up to 8 zs in a series of 5 lap driver training runs (or something of that nature).

Thanks for the interest in my engine.

Cheers Chris