Sean,
Depending on where I look, I get block weight diff between 302 and 351 at 25-45 lbs, all up motor weight diff between 70 and 100 lbs. The difference in deck height won't bring your center of ballance up much.
I don't recall how much torque I'm making, but I think it was somewhere just over 500 ftlbs.
My motor is standard stroke, the increased displacement comes from the bore. My motor is built to spin, I wanted to recreate the sound of the original cars, just with more hp. Besides, it's not like these are heavy cars. My wheels spin any time I want them to. Don't really need any more torque. Heck, I don't need the torque I have.
For yucks, I looked on another Ford site...they're getting 425-450 bhp on pump gas out of 347s. Of course, I don't know how much they've spent on internals or heads, but another 75 to 100 bhp with the same compression limits seems like a lot to ask for. Hope it works.
Hi Ron
The standard stroke big bore 351 definitly has appeal, hence my questions. From what i have read a complete 351 weighs 100lbs more. If ablock is even 50lbs more its on top as the weight comes from the taller deck. Plus the reciprocating mass is heavier too.
With a aluminum 302 block and light weight callies crank, olive rods diamonond pistons I think there is a saving of 180 or so lbs.
It laso depnds what block you have motorsport dart dart sportsman, they seem to have a40 or so lbs weight variance.
Butr yes if one went with an aluminun 351 block and lightweight internals with clevland journals the weigth difference might be on the order of 70 or so lbs maybe less.
Either way as you say its a light car, certainly light for the power. To me less weigth equals better braking and cornering, although maybe 100 lbs with this power is imaterial. But 200lbs is the weight of a passenger. Hard to say as I have only ever driven one Gt40 and that was a pukka 427 big block, yeah I loved the way the power came on, hence the continued interest in a 351 style motor. Can you let me have more info on your motor and who built it?
There are two types of 347's. One type has a 3.4 stroke and close to stock bore, the other type has a 2.25 stroke and a 4.125 bore which is possible to do with a dart block. A 3.4 stroke 347 with hydraulics is a 450 hp motor. But if you are running hydraulics and rev limited then might as well do both the big bore and big stroke 302, a 363 of which even ford sells a 500hp version.
So if one does a big 4.125 bore and a 3.25 stroke with solids and great heads like afr 205s then 525 hp is apparently attainable on pump gas with a 347, plus its supposed to be really snappy. With race fuel and 14.1 a 347 is over 600hp. Of curse no 347 is going to have the robustness and longevity of a 351 based motor. But if it lasts 15k track miles before refreshing I am ok with that.
That all being said a great 351 with great internal balance and revable does sound appealing.
How many miles have you done so far, before you are looking at the valves.