joebas

hi, new here, and aside from some strange threads this place seems to be pretty knowledgeable about smallblocks. So I have a question:

In terms of wringing the maximum efficiency from a smallblock, which is the best choice? I'll qualify that further by adding the requirement that it be streetable, from off-idle to wherever the peak may lie (no motors optimised for a narrow RPM range)

thoughts?

78novacaine

iTrader: (2)

for one, would prolly get better responses in the small block forum. but are we talking all year smallblocks? or just older stuff, cuz any year i would have to pick an ls7 crate motor - 505 very streetable hp from the factory out of a small block. and for older style sbc's, i would think a 400 small block or 383 stroker with midsize cam and a good set of heads would be your best bet for all around power

joebas

Any year, but thinking the later stuff is probably wringing more HP per cubic inch (normally aspirated)

I guess I should clarify, I am curious about efficiency in terms of maximum power per unit of fuel consumed, not overall absolute power.

Torovair

Which measure of efficiency are you considering?
MPG, BSFC, Thermal, Mechanical, HP/cid, HP/lb, HP/$ ???

joebas

as stated: "power per unit of fuel consumed"

(Brake specific fuel consumption would be equivalent, although the inverse - easily translated. Highest efficiency or lowest SFC)

Figuring the best gasoline engines are somewhere between 30-35% efficient, just wondering where the sweet spot for any of the small blocks is, and which is the best of the best.