With the major components covered in the last 2 "engine" posts, this entry concentrates on what parts are needed to complete the motor.
Lets start with the block - here it is all wrapped up as delivered after machine work.
Aftermarket (performance) "385 series" blocks are hard to find here but imported stock "rebuildable" blocks are certainly around. I found a supplier relatively local to me in Melbourne and found what looked like a very rugged block with hardly any lip (worn away by the rings) in the top of the bores. This block had extra castings compared to the others and seemed heavier - all good I thought. Unfortunately, while the block looked good, a crack was found in the valley quite late in the machining process. Not a big one but it would eventually have caused a problem. Thank you machining shop for not just completing it and supplying it to me!! The same shop knew the block supplier and got another one sent over. This time the surface rust in the bore was just too deep (after machining) and some of the elements added to make the casting hard would have been leeched out - making the bore softer. So a third block was sourced and this proved good. Sonic checks of the walls after the 0.030" overbore were good too - I finally had my foundation. Patience pays.
A bare and machined block is just a starting point though. I de-burred and stress relieved all the casting flash I could find and smoothed the oil return passage-ways and internal oil junctions. See below.
I also installed a Moroso oil restrictor kit I retrieved from the 351C. Having a roller-cam and roller rockers means you can safely limit oil going to the lifters and subsequently the whole valvetrain. This ensures the crank & big-ends get priority oiling while the valve-train still gets enough oil for lubrication and heat dissipation. Here is a shot of an oil passage where I tapped and installed a restrictor into. The restrictor is simply a grub screw with a specific sized hole drilled thru it.
Restrictors are installed in bearing saddles 2 thru 5, but only where oil travels from the crank main journal to the camshaft journal - you can see one here in the smaller oil passageway. The larger passageway in the saddle is the main oil supply port from the pump. Be sure to tap a thread deep enough to seat the restrictor below the saddle bearing face. No restrictors should be put in the front main saddle.
While on the oil system, I decided a long time ago that I needed a dry sump. This may sound overkill but I was always having problems with my distributor cam drive gear in the 351C. The steel gear on the roller cam ate up the bronze drives and kept fouling my oil system. I also had the usual oil-surge problems (even with a top of the range baffled sump) that I attributed to the the front oil pickup on Fords. Any right turn while under hard acceleration brought the oil-pressure warning light on! A dry-sump oiling system solves all these issues.
A 3 stage dry-sump pump removes the need to drive a stock oil-pump from the bottom of the dizzy and ensures I scavenge oil from the front & rear of the sump as well as supplying full-pressure oil (no matter what the car is doing) from a remote oil tank. On top of that, I can remove the deep "bucket" area of the sump to lower the sump profile height. This now gives me room at the bottom of the motor to drop the engine slightly lower in the car - if bonnet clearance for the big-block in the early Mustang becomes an issue.
The pump and related pulleys are shown above. Details are: JRP (Jones Racing Products) drive-hub, spacers and pulleys. The drive hub has a serpentine drive-pulley for the future alternator & power-steering pump as well as a radius-tooth drive-pulleys for the dry-sump pump. The 3 stage dry-sump is from Stock Car Racing. All 3 stages (2 scavenge, 1 pressure) are 1.5" wide sections. The vacuum created by the scavenge sections should give me some negative pressure inside the block to help me with ring seal.
You can see the home-made dry-sump I built above. I'm yet to plumb in the scavenge outlets and I am mounting the pump itself on the "oil filter" side of the motor. Fine stainless-steel mesh (from tea strainers) cover the scavenge outlets as a first line of defence from metal particles. A mesh windage-tray is mounted to the crank girdle to trap flying oil - so it then drains down the angled bottom of the sump and pools towards the scavenge outlets.
The piston-rings themselves are "medium tension" to help reduce friction and increase available power. The engine bearings are Clevite 77, non hardened - to suit the cast crank. Hardened bearings would have been used if I had a steel crank.
As for the cooling system, I thought about a stock and then even an electric water pump bolted to the front of the motor, but in the end I decided on 2 remote-mounted Davey electric water pumps. This approach frees up the whole front of the block so the camshaft belt-drive will effectively be the front of the motor. This saves a lot of weight at the front of the engine and keeps the centre of gravity well back behind the front wheels. I will have to TIG weld some coolant manifolds to cater for the twin pumps connecting to the single radiator inlet/outlet pipes.
Other items of note are the Felpro "1028" big-bore head gaskets needed to suit the A460 heads (to clear the large valves actually) and the ARP head studs ("SVO" type) to suit the raised inlet and exhaust ports on the A460 heads. You can see that the studs are actually longer on the exhaust side of the block to cater for the much raised exhaust ports!
The cam (mentioned in a previous post) has more than 0.7" lift. I'll keep the specific lift & duration to myself for now until I get the dyno numbers.
As added insurance against harmful engine harmonic, a neutral balance Fluidampr is used and I have had the crankshaft internally balanced. Stroker engines need all the help they can get in this area, but I believe my setup should ensure as smooth a rev range as I can get!
You can see the round slug of mallory-metal pressed into the crank weight at the lower left area of the picture below.
One of the things you find when dummy assembling an engine is shown above. The crank counter-weight is too close to the crank girdle. The girdle will need to be ground away wherever there is less than 0.060" clearance with a moving part.
In summary, what I have tried to do is put a package together where the component parts are complimentary with each other. I will not perform final assembly of the motor until I am nearly ready to fire it up. I want to avoid cylinder and bearing surfaces drying out - which can happen with an assembled motor just sitting around for a long period. As I have no way of knowing exactly when the Mustang will finally be completed, the engine will sit in pieces for now.
I will create another post that details the engine assembly, creation of brackets so the pulleys line-up, installation of the 8 coils that will run in "wasted spark" mode, etc, etc.
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