Thread: New block
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Old 05-21-2017, 08:43 AM   #201
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Join Date: Jan 2011
Location: Central Ohio
Posts: 2,317
Default Re: New block

Couple More Options, Ideas to Consider:

1) Making a 21 stud version would be the most valuable if the outside of the block really looked like an original - so that somebody taking a pretty serious look at it in a car could not tell the difference. As others noted - this demands that the front of the block have the necessary configuration that a "pump in head" 21 stud would have. (Lots of little nuances here).

2) The internals of the 21 Stud could mimic the 24 stud - such that you could run a 24 stud crankshaft, rods, bearings, etc. - in it. I would deliberately setup the mains to support the later cranks - due to bearing availability.

3) Bores: You would want the 21 stud bores to be at a minimum 3 3/16 inch - such that the later 29A through 8BA rods would fit through the bores.

4) Oil Pan: I have not looked enough at the pan rails to compare 21 stud to 59A to 8BA. I will give this a closer look - but you may have to have some provisions to support different pans and breather setups. A 59x pan does look different than a 32 - 36 pan and the breather systems vary quite a bit.

====================== Back to General Ideas ================

A) Simple is Better for Most: Most folks will want to easily be able to buy/machine/setup a block using all their components. This give them maximum flexibility for both stock and performance applications.

B) Design Improvements - Strength and Material Thicknesses: While the above is true, nobody is going to be hurt by better strength in key areas, more material/thicknesses in weak spots, better ports/flow, etc.. So - the key is for the design(s) to support both --- giving us all the BEST of all worlds. (I know, this is the most difficult engineering/design challenge - the more options, the more complex, the more costly to produce).

C) Oiling the Lifters: I've seen some talk about pressurized lifter galleys. While I'd love this as "a configurable option" - it may present some real problems for most (if done with one big long galley like many OHV designs). The reason is that the stock lifters and many performance variants are NOT designed for a pressure galley - so many lifter designs will leak pressure (through the lifter). If there was a plug/port to drill out to turn this capability on/off, then the builder of the engine could decide how/when to use it. I would use it for many race situations where I have high lift - and or a lot of 'side load' on the lifter bore (think big roller cam). Tod - be happy to talk about this more, show you a whole range of lifter designs, etc..

D) Priority Main Oiling - 100% filtered: Yes - this would certainly make sense, but would probably require an oil galley down the side of the block - or external lines . . . could be done, but might be a pain. We use external priority main oiling on our Flathead Cadillac Bonneville engine - which has a long galley cast into the side of the block. I do think it is important for the design to include a 100% filtered oil setup - but one that uses the stock 49-53 pump in the stock location . . . as this is what MOST people will run. These blocks will not be approved for Bonneville racing - so there will probably be almost nobody who cares about dry-sump setups.

E) Different Oil Pump? - Another idea/option to ponder - is to see if it is possible to redesign the rear main cap to support a SBC style pump - with a 'drive shaft setup' coming from the stock location. Now - this might be total overkill, but I'd sure like to be able to use better quality pumps than we seem to be getting for flatheads these days. (I know - this idea is probably a bit too wild and expensive for most!)

F) Intake Ports: There has been a lot of chat about better flowing ports with solid/press-in guides (like the Flathead Cadillac). I think a LOT of improvements could be made here - as long as you solve the bigger issue of how to bore the lifter holes - obviously this is the big pain in the butt portion of the problem. I'd love to see a much better designed intake port, bowl and guide setup - that would be worth the money in itself (for us performance hounds).

G) Exhaust Ports: Yes, the challenge in the center is the room that it takes to improve flow. Given the larger bore desires (3.5"), you might consider making the ports "taller" to increase the flow - as you'll have problems going 'wider'.

H) Cubic Inches and Performance: We really need more cylinder wall thickness than we have today at 3 3/8" bore -- I'd like to see .220 or so (such that I can go to a 3.5" bore and have good wall thickness for boosted/blown applications).

I) Crankshaft Throw Clearance: I'd probably pickup a 4 3/8" stroke SCAT crank and a H-Beam rod - to see how the block and cylinder clearances setup on the bottom end.

J) Camshaft Journal Material, Cam Lift and Crankshaft Clearances: Many of us would love to have more material in the front/center CAM bearing areas - so we could use larger bearing diameters for larger lifts. One thing to checkout (with the 4 3/8" crank and rod) is what type of clearances do you have with the cam? How close are you getting to hitting the cam? While I'd love a 'raised cam' design (to clear the crank), this causes all sorts of drama with valve angles, port designs, new cam/crank gears, etc.. Not worth doing . . . but worth at least checking things out in your design.

K) Mains 3 or 5: Would be great to have a 5 main block as a potential option. Now - this would only be for guys chasing more serious horsepower levels --> Arduns, blown engines, etc.. There are definite limitations on the available journal sizes for the two "new mains" - given the dimensions of the block -- there is only enough room for a 1/2" to 3/4" side bearing (depending on throw thicknesses on both sides, what type of radius numbers are used in the corners, etc). Obviously this 'market' is much smaller than the guys who want to run normal crankshafts -- but my guess is that the high-end of the market might want this option.

L) Main Caps: If you make the block stronger in the main areas (very important), then you should also consider much stronger/better cap designs -- with enough material in the block to support 4 bolt caps - maybe quite wide to spread the clamping load out. (Think after market 4 bolt caps for performance SBC motors). Also, I would get rid of the 'half circle' cap indexing methods in use on the stock engines -- no reason to have these index methods when you can use some more modern methods. Also, by NOT having the semi-circular index methods, would make it a LOT easier to retrofit a full stud-girdle across the bottom end. Guys like me (especially on 3 mains) - will probably design a whole 2.5" or so thick stud girdle that covers the whole pan rail. Having better/easier indexing methods (not 6 half circles bosses) would make this easier. As a matter of fact, boy would I love a stud-girdle 'option' to be cast out of cast iron and available as an option for the block. Beats the hell out of having to fabricate one out of aluminum billet or steel.

Okay . . . too much coffee today . . . too many ideas to ponder and I better get to work actually getting something done on my cars - versus pondering the future!

Take care and I LOVE this whole thread and project.

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