If im running an A15 with flat top pistons, ported head, 40mm DCNF Weber & 4-1 extractors, what will be the best cam profile for mid range torque and a kinda smooth idle?...so far, the reccomendations i received is 270deg. How will my idle be like if i use a 270 profile. And, where will my peak torque be? ( estimation )

What is the stock profile?...is it 240?
Thanks alot mates....

Quote:

with a heart shaped chamber it will be in between
270=1000-6000
280=2500-6500
290=3200-7000
300=3800-7500
310=4300-7700

more important than you pistons and carbs are your gearbox and diff and wheel size\type size when choosing cam (take it for a drive with a tacho and figure out where in the rev range you want your torque (no matter how good or bad your engine is this will be the same rev to speed ratio) (i always go for the revs that the motor drops down to after you have changed gear at your desired peak then you start at good torque for the next gear) eg: out of corners or off the line. then once you have your cam installed you tune your carb and ignition to match the cam

Yup, i got u...as for now ( engine still stock ), my peak torque is at about 3.3k, so that makes me shift at abt 5k on 2nd gear so that the rev drops to 3k on 3rd gear. But it takes time to reach 5k on 3rd or 4th gear. So, im planning to get the cams working best from 3000-7000rpm's. So, i hope 290deg should be good.

Anyway, what's the stock profile?

Stock Datsun 1200 for A12 is 248 degrees. See Valve Timing.

I would guess that A15 cams are similar, the bigger displacement will move the torque curve down a bit with the same cam profile.