My 422 smallblock build

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SSG_Karg

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Sooooo, this engine has been a very long time coming. I picked up a 340 shortblock about 10 years ago and stashed it in the corner of the garage and proceeded to daydream of building a gnarly-***, tire-frying, rip-roaring beast of a smallblock.
It is dated 7/70 so I assume it came in a 71 model something or other. When I picked it up it was already.030 over with forged Venolia pistons on stock rods with a stock forged crank. I took it to the machine shop and they said it needed to go to .060” over to clean up. Welp, might as well stroke it then!
Sold the pistons, rods, and crank and started looking for new guts.
Ended up ordering a stroker kit from Rod Bloomer @ BPE.
Then the project stalled as I continued to collect parts and pieces and squirrel it all away in anticipation of a day when I would have the time and money to put it together.
And then I started to follow this thread New 408 build finally started
and it lit the fire under my ***.
So now it begins.
I completed almost all of the Guitar Jones oiling mods including tubing the passenger side lifter gallery and shut off the oil to the driver side with a set screw under the #1 main bearing.
I’ll try to take as many pictures as possible and document as I make progress. I am not a professional engine builder so please feel free to chime in with advice, tips, or questions any time. And if you see me doing something retarded let me know.
 
My only advice is to not start with a max over bored block. Thin walls are a detriment to power. The thicker the bore, the better. My 2c
 
I would recommend a sonic check to make doubly sure your major thrust surfaces are good for a stroker.
 
Washed the block and got a quick coat of paint on her and got the freeze plugs beat in.
Layed the crank in and checked main bearing clearance with Plastigauge. All measured between .0015 - .002”. Crank endplay measured .0025”. The crank is a forged piece from BPE with a 4” stroke and 2.10 rod journal. The rotating assembly was internally balanced by Courson Racing Engines in Emlenton, PA to 1852 grams.

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My only advice is to not start with a max over bored block. Thin walls are a detriment to power. The thicker the bore, the better. My 2c

I would recommend a sonic check to make doubly sure your major thrust surfaces are good for a stroker.
I knew the .060” over was gonna get people excited! I agree that the thicker the bore the better but the machinist that did the boring is a lifelong seriousMopar guy. Serious like he owns 2 mint Superbirds with sequential vin numbers. He has built more Mopar engines than I could even imagine. He said this block looked great and could handle the.060 over easily. Did he sonic test it? No. Do I trust his word as an expert? Yep. So I’m gonna run it and when it splits a cylinder I’ll take back to him for a sleeve.
 
And yes I’m using ARP main studs and I did not have it line bored. GASP! I can spin the crank with two fingers.
 
And yes I’m using ARP main studs and I did not have it line bored. GASP! I can spin the crank with two fingers.


That thrust is a bit tight for me. Make sure the studs aren't forcing the cap to the front or rear and changing into the thrust reading.

I always set the thrust by leaving the number three cap loose and with a rubber mallet or a dead blow or something and a piece of wood and gently smack the crank to the rear and then back to the front and then torque the cap.

Like I said... That's on the low side for me. .004 is my minimum. You've got to get some oil in there.

Edit: I forgot to mention that Ramm I think it was and maybe MoparOfficial too drill a small hole in the bearing and block where the oil feed goes up to the cam bearing to get pressurized oil to the back side of the thrust. If you are at .0025ish you may get by with it if you are getting pressurized oil in there.
 
That's going to be a whole lot of fun there, what's that going into?
 
Glad you are on your way and I look forward to following your progress. I’m not an expert by any means but .025 endplay would keep me awake at night.
 
I forgot to mention that Ramm I think it was and maybe MoparOfficial too drill a small hole in the bearing and block where the oil feed goes up to the cam bearing to get pressurized oil to the back side of the thrust.
I’ll have to look into that mod. If you happen to find a post or thread that explains it more please post a link here.

That's going to be a whole lot of fun there, what's that going into?
This engine will initially be put in my 72 Duster with 4 speed and 3.91 rear. I have a rough 70 Swinger that my son and I hope to build into a 70’s ProStock style race car that may eventually get this engine.
Glad you are on your way and I look forward to following your progress. I’m not an expert by any means but .025 endplay would keep me awake at night.
I know .0025 is on the tight side but it is within the .002-.007” spec. I will probably fiddle with the caps a bit to see if anything changes but I was pretty careful the first time to get it right. I tightened the rear main first and worked my way forward, skipping the #3, and worked it back and forth. Then held it forward and tightened the #3 cap.
 
I didn't see where you notched the bottom of the bores to clear for the rods?...
 
I didn't see where you notched the bottom of the bores to clear for the rods?...
Not needed with this combo. The rods are 6.125” h-beams from Callies with arp 2000 12point bolts. Lots of clearance. I’ll take pictures and measure the exact clearance when I get to that point. I did previously have all piston/rod assemblies installed for mock up with no issues.
 
Not needed with this combo. The rods are 6.125” h-beams from Callies with arp 2000 12point bolts. Lots of clearance. I’ll take pictures and measure the exact clearance when I get to that point. I did previously have all piston/rod assemblies installed for mock up with no issues.
Mine is notched for the stroker, but didn't need it because scat said I beams don't need it but they did say it was needed for h beams but that was a different brand..
 
Mine is notched for the stroker, but didn't need it because scat said I beams don't need it but they did say it was needed for h beams but that was a different brand..
I “think” it usually comes down to the type of fastener used. Factory style stud/nut requires notches where as cap screws do not. Just what I’ve seen so far.
Edit: I’m speaking about 4” stroke combinations. I’m sure other strokes will differ.
 
I’ll have to look into that mod. If you happen to find a post or thread that explains it more please post a link here.


This engine will initially be put in my 72 Duster with 4 speed and 3.91 rear. I have a rough 70 Swinger that my son and I hope to build into a 70’s ProStock style race car that may eventually get this engine.

I know .0025 is on the tight side but it is within the .002-.007” spec. I will probably fiddle with the caps a bit to see if anything changes but I was pretty careful the first time to get it right. I tightened the rear main first and worked my way forward, skipping the #3, and worked it back and forth. Then held it forward and tightened the #3 cap.


That .002-.007 is for dead stock stuff. If you start beating on it or racing it, the spec is .004-.008.

I'm hoping someone here who can use the search feature (I can never find anything) can direct you to the post where drilling the hole is outlined.

I've never done it. So I don't want to say exactly how they do it, or the hole sizing, because I don't want to tell you the wrong thing.

BTW, it might seem like we are picking the fly poop out of the pepper here, but if you are at .0025 and you get it to .0040, that's about a 70% INCREASE in clearance (rough math...if you went from .002 to .004 that would be a 100% increase in clearance).

Like I said, I'm a chicken. My wife will testify in court to that.
 
I always say to much is better than not enough and that goes for bearing clearance too.
 
Maybe take it to the drag strip to break it in like I did and beat some clearance into it! LOL... :poke:..
 
Just don’t prescribe to the school of “It’ll clearance itself” on that one. Most times that will work in the lower ten thousandths numbers but not so well in the thousandths. My personal preference is still about .002-.0025 or close to it on the main bearing clearance.
 
Just don’t prescribe to the school of “It’ll clearance itself” on that one. Most times that will work in the lower ten thousandths numbers but not so well in the thousandths. My personal preference is still about .002-.0025 or close to it on the main bearing clearance.
I plan to double check all main caps to see if I can get a whisker more clearance. If not I’ll pull the thrust bearing and massage it a little.
 
How did you “SET” your crank?
Laid crank in saddles. Screwed in studs. Placed caps over studs. Tapped down with rubber mallet to seat caps. Pried crank forward and backwards. Tightened 5,4,2,1 caps to 85ft/lbs. Pried crank back and forth again and tightened #3. The caps have very little wiggle room with the ARP studs.
 
I too I like to place my caps over my studs as by doing so I know I have clearance. Some small differences on how I set my crank. I tap my caps down with the handle of s plastic mallet the I take a brass hammer and smack it forwards and backwards a few times. Then I torque all my main caps to 25 foot pounds and I throw my dial indicator on to check my clearance. If I don’t have at least .005-007 it’s coming apart to sand my thrust bearing. I repeat these steps till I have that clearance then I finish my torquing and check final clearance. You have to get that thrust bearing squared up.
 
Hey before you go to far check your oil pump drive into the bronze bushing to make sure it fits good. And put a 1/4 inch rod down through the top oil pressure hole to double check to make sure the 9/16 plug was installed under the rear main cap. Easy to fix now, hard job later. Measurement from top of block to plug should be 7 1/2-7 9/16 inches.
 
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