Has anyone tried one of the 11" + blocks?We are considering building a long block using a 4.75 crank,4.535 pistons and obtain a 1.60+/- crank to rod ratio.The heads would be Dart Race heads.

Ccan,
I have been running the taller block (11.665") for a few years.. have had problems and still sorting it out. Hoping that Next year will be my year. I am running a 4.25" crank and 4.600 bore with an 8" rod.. 1.8 ratio.. everything is expensive. Sheet metal intake, special oil pan, etc.
I wish now I had gone with a longer arm to take advantage of the tall deck. If I can ever afford it.. the next crank will be 4 7/8" and Dart 14* oval ports... That would be a mule to test Bravo's behind.. *S*..

If I had it to do all over, I would look hard at off the shelf parts and build a BowTie 632 or 598.

Dick

I agree. I built the 598 because the bottom of the cylinders require some chopping for rod clearence in the 632.

All Dart products.

DAVE

For years rod stroke ratio has been argued. Longer rods being perferred. In the last 10 years this thinking has changed do to R&D. I would build the combo to achieve the goals you have set and let rod/stroke ratio fall where it does.

Basically,the thought for considering the 11+ block is directed at durability, on pump gas.The long rod should delay ring flutter,require a slower lift cam,reduce cylinder wall side load and hold the piston close to the head slightly longer.The down side includes added weight,angle matching the heads to the raised cam,the DRCE pan rails,front cover and the intake spacers.What did I forget? Meanwhile,we recently dynoed our first dry sump 615 blown non inter cooled that made 1,000 HP on pump gas w/5.4lbs.boost.The idle torque is 140lbs. @ 850 rpm.However,the block is 10.2 and the rods are 6.625.