We decided to go with a stronger foundation (Dart Big-M block) for 2012.

We know the aluminum blocks are faster (due to lighter weight) but we also feel our old block had been damaged enough it was probably not up to the 1000 HP runs anymore. We decided to go with the Dart Big-M block with steel billet main caps. We ordered the 4.600 tall-deck block and I figured when it arrived it would be ready to clean up, hone it a bit to get the right clearance for the 4.600 pistons. OK, so I expected a bit too much. The block needed a lot of casting flash removal, the edges of the lifter bores were razor sharp and Roeder Performance massaged just about every edge on the block. While the block is killer-strong it surprised me that we had to do so much hand-grinding to obtain proper clearance for the crankshaft, rods and pistons on what I expected to be pretty much ready to go. Jay, owner of Roeder Performance, spent over 30 hours with the hand grinder notching out pan rails, removing part of the block casting and removing some lower cylinder wall to get the 4.750" crank and the rods to clear. I would think that since this is Dart's biggest bore tall-deck block and some of the pan rails has been CNC-machined they would have finished the clearancing for a 4.750" stroke crank. They do not and I just want you readers to be aware of that. It is not a deal-breaker but it is a time consuming project if you do not have a CNC program and the machinery to do  it the quick way.

That said, the Dart Big-M block is a monster as far as webbing, oil system upgrades and I am sure our 1000 HP goal won't stress it to its limits at all. We did learn a few other things that the home engine builder might want to take note of. The block is a very dense and hard cast iron. Honing it with a basic small-shop hone takes a lot of time and patience (as Jay will attest to!) Came out perfect but not a two hour job for sure unless you have the latest state of the art honing equipment.

Once the block was clearanced and the rotating assembly balanced everything went pretty smooth. Just relied on "Jay's machinist touch" to get all the little things to fit and clear. One such item was the belt drive cover had to be machined to clear the oil galley plugs and due to time limits he had to fabricate the special spacers we needed to use the valley-located head bolts. Dart offers these but the warehouse we use did not have them.

The cylinder heads are our trust Dart Pro1 355-CNC aluminum heads. Nothing special done to them and they have been excellent for five years with basic maintenance.

We are trying the new Edelbrock Victor 632 intake manifold. Much larger plenum and an improved and straighter shot at the intake valve. Looks good and the ports were so close to matching we didn't touch the intake so it is "out-of-the-box".

We are still relying on the Comp Cams roller camshaft to produce the power. It is a "smaller cam" in that we only wanted about .760" lift and a profile that would be easier on valve springs. One thing I have learned about radical cams; you can win the race if you are breaking springs.

We reinstalled the Billet Fabrication oil pan that gave us fits with oil pressure in the shutdown but as I write this we have had the dragster out a couple times and that problem was solved by running 11 qts of Comp Cams Break-in Oil in the pan and 3 more qts in the Moroso Accumulator. That is a lot of oil but I don't care, we have oil pressure and that is more important to me than 5 or 10 horsepower.

Once the engine was assembled we were "leaning" on Jay to get it on the Roeder Performance Stuska dyno the same day. We topped the new intake with our tried and true Quickfuels 1250 cfm gas carb.

After a couple easy pulls to make sure all was well and a quick look at the vales lash it was time "to make me nervous". Something about standing outside a window and watching all that money and time sitting there being wide open against the dyno's water brake for what seems like a 5 minutes (although I think it is like 10 seconds).

First pull: Ran good all the way through and I think it peaked at about 986 HP and 860 ft/lbs of torque. 34 degrees timing.

Second pull: We added a car spacer so we have two-1" open spacers. Timing was 34 again, two more turns on vacuum pump relief valve (to add some vacuum), 997 HP at 6200 RPM and 871 ft/lbs torque at 5500 RPMs. Average H.P. on the sweep (5000-7000 RPM) was 933 H.P. and 821 ft/lbs torque.
We tried a few things the next three pulls, took 2 degrees timing out, took one spacer out but the 997 H.P. was still the best pull. Pretty stout considering the dyno was pulling in 95 degree outside air with about 40% humidity and a 28.8 barometer. Corrected altitude was about 3600 feet.

The on-track  results of the engine rebuild will be in the next issue of DRO. Hope you check it out.