The Heart of the Beast

Pressure gauge w/line adapter

Ford Small Block Dry Sump

Unlike most of this project, I decided at the outset to build a dry sump motor. For two reasons; 1) a dry sump pan is only about 4″ high which meant (I believed) that I would not have to alter the cross member as is typically done with V8 transplants in MGBs and 2) because I had never built a dry sump motor before and wanted to give it a go.

As it is abundantly clear if you have read my Dry Sump SBF write up, building this kind of motor has absolutely no financial advantage over building a more traditional wet sump power plant. In fact, it’s quite the opposite, the dry sump parts alone will cost in the neighborhood of $2,500 -$3,000 (in comparison to say a typical wet sump set up costing maybe $500) and then there are the engineering challenges of locating your oil tank, running all of the plumbing, finding a place for the belt driven pump, getting the motor moved back far enough to accommodate all the business hanging off the front of the motor (drive mandrel, gear, etc.) and we’re not even getting into the snickers you need to prepared to endure when you start asking questions of people who actually know how to do this.

It has been, to put it mildly, an adventure. I’ve learned a ton along the way and, I’m sure, provided at least a start on the college education of the children of several of the parts vendors I’ve used. It’s nice to be valued.

The Block—This is a scratch-built motor that started with what is popularly called a ‘seasoned’ block. ‘Seasoned’ is a euphemism for used. It actually means the same thing but it sounds a lot nicer. In my case, my ‘seasoned’ block cost me a hundred bucks—hands down the least expensive part that went into or on the motor—and came to me with the factory cross hatching still in the cylinder walls. I probably could have installed a set of standard bore pistons and been done with it but I wanted a little extra displacement so Edger Engines (where the block was prepped) bored it .30 over. From there, the cam journals were lined bored and the crank, pistons, and rest of the rotating assembly were balanced. Yes, probably over kill but I’d never bothered to have it done before and figured this was my chance. We’ll see if it has any effect on power output.

Jack Edgerton, the block builder and local engine guru to the roundy-round crowd in my area, suggested decking the block to a near-0 (.005) tolerance to raise the compression of the motor, about 10.5:1. I’ve previously decked blocks only to make sure the surface was flat so this was the first time I had it done to actually increase performance, although it was (and maybe still is) a common practice “back in the day” to make more power. As I said, this has been a learning experience and, in this case, a re-learning experience. Having the block bored, the rotating asembly balanced, and the decking were the extents of my outsourcing on the dry sump motor. Everything else was done out in my garage.

V8-on-a-budgetParts and Pieces—One of the ways I saved money, maintained a high level of quality, and managed my budget to get the most horsepower for my buck was to become a religious visitor to e-Bay as well as any other car forum and aftermarket supplier that might have Ford small block parts…that, and to have read George Reid’s, “How to Build Max Performance Ford V-8s on a Budget” so many times I could quote it chapter and verse. Tom Monroe’s book, “How To Rebuild Small Block Ford Engines” is also a great resource.

The big deal here is to put a plan together and build to your plan, which is what I did. This enabled me to shop How-to-rebuild-SBFfor the best deals and be patient about sourcing parts. It also helped me develop options for parts, cylinder heads as an example. The Max Performance book called for a particular specification on the intake and exhaust valves for the heads. These specs fit a number of cylinder heads which meant I could pick and choose from not just one, but several makers and get the best deal. In my case, I was able to purchase a set of brand new, aluminum Ford Racing “z-heads” for less then $500 from a fellow who was removing them from a newly purchased crate motor—about half of what they would have cost me new. Good thing too, I would need the money when it came to buying all of the dry sump parts.

Pistons were Speed Pro hypereutetic and came from e-Bay from a builder who unwisely purchased his .30 over high-end cans before he actually had the motor bored. Oops! Turns out he needed to go .40 over and was happy to sell me his now useless pistons for $10 each. Again, less than half of what they would have cost me new. I won’t go through the entire parts list, but you get the idea. If you want to make big power on the cheap, start with the facts, put a plan together, figure out at least three options for every part you’ll need, and then be patient and diligent when you shop. It’ll all pay off when you’re done.

The Specs—As mentioned, I basically used the recommendations straight from “How to Build Max Performance Ford V-8s on a Budget“, including several of the specified manufacturers (Weiand, Autolite, and Ford Racing to name a few).

  • Block—Ford 302, bored .30 over, decked to near-0 tolerance, with the oil galley plugs tapped and threaded plugs (instead of the press fit kind) installed. The cam journals were also lined bored, brass expansion plugs installed. After it had been thoroughly cleaned, the block was painted with two coats of Ford Grey engine enamel (brushed on) except for any mating surfaces.
  • Rotating Assembly—Crank was a new stock Ford 302 nodular iron crank, nothing special, standard (not over-sized) bearings. The rods were also stock C80E Ford rods but with larger diameter, 3/8″ ARP rod bolts installed. Pistons were Speed Pro hypereutetic, with the fly cuts deepened just a taste to accommodate the lower deck height (and resulting deeper valve movement). The entire assembly was balanced including the counter balances on the crank (not just weighing the pistons, rods, etc.). Damper was a 50 ounce from early 302 that was quite a bit shorter than the stock damper.
  • Cam Shaft – Ford E302 roller cam with a 107 degree lobe separation, opening at 224, closing at 284. A little milder than what the book called for  but a better choice for the carburetor and intake combination as well as for the street.
  • Valve Train—New aluminum Comp Cam 1:6 roller rockers, new Ford Racing pushrods to match the lift of the cam.
  • Cylinder Heads—New Ford Z-heads, 2.02″ intake valves, 1.60″ exhaust valves, rocker studs and guide plates installed. These flow significantly better than the popular GT-40X heads.
  • Pistons—Speed Pro hypereutetic, fly-cut with matching ring set (don’t scrimp on the small stuff)
  • Flywheel—Fridenza aluminum, 50 ounce imbalance. Faster spin up, dead drop when you’re off the throttle. These take a bit of getting used to to drive on the street but it’s not my first one so I was comfortable with the choice.
  • Intake Manifold—Weiand Stealth, dual plane bought used for $75. This is where I departed from the specs in the book, which called for a single plane manifold…they’re great for racing but not a good choice for the street. I needed one that would give me good all around performance. Yes, I’m sacrificing something at the track but I also don’t need to keep the RPMs above 4,000 to make good power. It’s always a trade.
  • Carburetor—A vintage Autolite 4100, vacuum choke (set it and forget it) worked over by Pony Carbs in Texas (sadly now defunct) to flow 560cfm, set up for today’s ethanol laced fuels and matched to the rest of the engine specs. It flows less than what the build sheet called for (750cfm) but was better match for the manifold.
  • Timing—New Trick Flow double roller chain and gears. Ford 351C short-nosed water pump (reverse rotation) and matching timing cover. This helped with the motor set back.
  • Clutch—Grip Force heavy duty (good to 425 horsepower or so)

Assembly—I put this motor together “by the book” meaning I observed keeping things clean, matching mating surfaces, and using the correct lubricants (anti-seize, assembly lubricant, locking compound, etc.) where called for. Every fastener was brand new and everything was torqued in two stages, then re-checked at least 48 hours after to ensure the proper specification had been achieved.

According to Jack Edgerton and both books, this particular combination of parts and pieces should make something in the 450 horsepower range. I’m skeptical but, if it even gets close, I’ll be beyond thrilled. My guess, given the carburetor and manifold changes is something more like 350-375 on pump gas. That estimate flies in the face of everything that seems to be popularly held but the dyno doesn’t lie so we’ll see when I get a chance to strap it down and get some definitive evidence. In the meantime, even if it only makes 300HP or so, the car will weigh less than 1900 pounds when complete and is still going to go like stink.

Here’s the build sheet for those interested. Keep in mind, I built this over a four-tear span so prices have obviously changed as has parts availability and some parts may have been substituted.

302 Build Sheet

 

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