Low speed torque and driveability ?

ir3333 said

When driveability is discussed concerning longer duration cams it is the the low rpm power that is questioned.
I've often mentioned that when i ran the mopar performance .474 or comps XE268 low rpm torque was not strong.
if i hit it when driving slow, acceleration was lazy until higher rpms were reached. Everything else was fine.

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Here a 340 torque stock on the left fully modded with an xe268h cam on the right, it's not showing under 3000 rpm but it's unlikely the xe268h is making less stock to at least 2500 possible 2000 rpm.

So your driving around at say 2000 rpm you hit the throttle, at 3000 rpm all these mods make more power that even stock peak torque so that's no problem, under 3000 rpm how long do you really spend there 1-2 seconds ? Say the xe268h takes a somewhat drastic drop off in torque, at 2500 rpms there tied and by 2000 rpm it's 20 lbs-ft shy of stock 340 is that really the cause of this lazy part. Say where talking 280 lbs-ft that would mean any small engine like a 4 cylinder would be lazy at any hp eg.. 400 hp or a big cammed 440 that's got soft bottom that's still making more torque than these 340's wouldn't they have no choice but to be lazy the whole time. It's just not making sense to me.




Phase 1:Stock 340 baseline, Chrysler electronic ignitionPhase 2:Replace small production AVS with Edelbrock 800 CFM carbPhase 3:Replace factory HP manifolds with Hooker 151/48-inch headersPhase 4:Replace factory iron 340 HP intake with Edelbrock Performer RPM Air GapPhase 5:Replace SSI springs and retainers with Engle #604LS retainers and #993 springsPhase 6:Replace stock 340 HP cam with Comp Xtreme Energy 268