building a mild Daily driver 318

AJ/FormS said
So if I understand this right, the ActionPlus, and a 600, and a 340type cam, dual exhaust,a valve job on stock teener heads, with the bowls mildly opened up, will make in the neighborhood of 310hp;more power than a stock, brand new 1970 340 engine?
What are you thinking? what did I miss?

No, almost certainly not. Much more likely somewhere solid in the low-mid 200hp area. Should be around the place a 302 swap that doesn't see excessive port and head work (enough to buy a Magnum motor) would go. More than that- it's relative. I find it hard to believe the numbers in the 300s would be actual on most builds.

Now gearing and 904 not the same- yeah, it could be quicker than a factory 340 car if it's down a bit of HP or closer to a '73 340. I think it'd run the numbers with the rest of the car around it even if it didn't

AJ/FormS said
For a Streeter that spends most of it's life at under 3500 rpm, I will take Compression over flow. 3500rpm is about 38 mph with 2.94s in a 904-first gear. Even with 3.91s, 3500 gets you about 30mph.Your heads could flow 700 and it wouldn't be worth a hoot. But 3 points of compression will pay back big time,all the time, every time.

The reason I'd think about it the opposite way is I've never had a 2bbl run near as good as a 4bbl, even the ones that were acceptable. Everything before is not too complicated, makes it easier or no more difficult to obtain good reliable consistency from it, and everything before will help some towards the ultimate goal. It'll run a little bit stronger on the topside with just a 4bbl, it'll pull a bit harder with headers, it'll have a stronger sound with the headers, and it'll be easier to make it run near perfect with the 4bbl. Its condition and reliability are primary, then comes the rest. The thing about compression is if you have only the compression and the rest of the build's not there to match, not only will it be about as much a dog- but it won't behave well either or will need higher grade fuel. Been there, done that- won't again. Sure, it's fine to band-aid in a car that only ever has a driver and never really gets beat on- but best case you're gaining nothing or on the worst hand you're losing reliability.

Off-idle's important but the modern performance most are trying to replicate is higher HP and less torque. Steep trans gears and steep gears make up for the lack of grunt the motors themselves possess. Sure, a stock 318 has loads of low-end grunt but if you're not trying to have a yard cart- it doesn't need to keep it all and most given up to gain mid and upper range will be better rather than worse. In a 4800 lb truck, I'd rather give up off-idle if it means a healthy mid-range and there's no reason for any different in a far lighter car with less driveline loss. A meaty bottom end is far less fun than the healthy mid-range it'll cost. Part of the problem is the perfect "torque" build is stock. Not one thing different. 10:1 in a motor with a tiny cam with a small carb and small ports would be a nightmare- it'd be slow, but you wouldn't have the low hassles of a stock motor.