So I'm getting ready to start a new build, of course I want horsepower for my big 69 B body. I'm starting with what I have now , trickflow 240 heads,intake and 1 7/8 headers. Harland sharp rockers. So I'm gonna go with a solid lift roller.
What is the best was to go on the bottom end? 400 block, 440 crank stroker?
Also whats good rods,and how light are the good pistons nowadays?
Hopefully only American made products i don't want anything made with overseas steel.

So anyone who has had success let's hear what you have to say !
Thank you

I'd do a 4.25" stroke RB 440 block w/ Molnar crank & rods and Diamond pistons.

I like the 400 low deck 512cid, good luck on American made crank & rods

The engine I built last year for my Coronet is the best street build I've seen so far on the dyno. 4.25 crank, 7.100 rods and pistons had a dish so final compression ratio was just a hair under 10:1. Trick Flow 240 heads with a port matched TF intake. I used a Holley Sniper since that is an easy way to get great street manners. The camshaft is key. I had Porter Racing Heads spec a custom hyd roller cam that gave me lots of torque down low but still pulled hard enough to make 600+ hp at the top.

I started building my first pump gas stroker motor with this combination
It was a bad block that needed four sleeves to make it usable and I used a set of ported big valve 906 heads with 9.25 to 1 compression ratio and low deck Eddy six pack intake with 1970 440 stock carbs tuned well. That motor made 644 Ft. Lb. at 4500 RPM and 612 HP at 5500 RPM on CA pump swill back in 2002
I've built a bunch of stroker motors since then in both 440 and 400 blocks for street and strip and race only, I won't build a stock 440 block now if the HP goals are above 650HP due the main webbing cracking
I always sonic test each block before starting also
Good luck on your deal

4.25 crank, 7.1" rod in an RB 440. It all drops in with no grinding if you do the 2.20 Chevy rod journal.

I like Molnar stuff. Just so you know, everything originates in China at this level. Who finishes the final machine work and does quality control is what matters.

The Mahle pistons are nice pieces as well.

The forging is done in China but the raw materials are often from the USA and the finish machine work is in USA so the whole concept of country of origin is very fuzzy.

I did a 512 using a 4.25 440source crank, 6.7 scat rod and 1.12ch mahle piston thats only 453grams.
I’m sure it was overthinking going with a longer rod for less angle and a lighter piston.
The kits come with 6.535 rod and 1.32 piston.

If this was a 400 block build you did good
If it was a RB block then the 7.100 long rod is a little better on reducing cylinder wall loading and friction reduction from the thrust loads from the rods from the longer stroke

I agree, build the 511 or 512 using Molnar components and don't skimp on compression if you have good gas. I would run at least 11:1 as the compression. makes the heads breath better. Keep the cam in the 250- 260@50 with .600-.650" lift on a 110. That should make a very fun car to drive. The 470 is a nice motor too, but in a big car like that i would rather have the 4.25 stroke. Match the vert and good gear for what your doing like maybe a 3.73. Not sure what kind of driving you do, but if around town and to the cruise ins i would put some stall to it. Just for example i use a 5400 8" stall and do a lot of street driving. The trans rarely gets over 180*, so don't be afraid of stall. If you do a lot of long distance driving, than your components will have to be more conservative. If power brake, keep the cam in the 240-250 range. That will make tons of torque.

Did you ever build the 400 stroker ,440 crank and bb chevy rods?

Ya but I've seen some really soft steel come out of china. Steel thats supposed to be t stock and compares to 1020 so all the best final prep in the world wouldn't have help in that peticular situation

Thats interesting, how did you find that out ? Probably not the case with evey manufacturer. I've seen so much junk from China, broke camshafts, spindles, shafts, Rockwell ratings way below specs

Anyone ever do the the old 400 stroker with a 440 crank big block chevy rods and lightweight pistons?

470 cubic in. 400 low deck here with stock studded main caps, stock 413 forged off-set ground crank, 6.385 Chevy Eagle rods, home ported RPM's, 2" Super Comp fender-well's, Isky .680-.660 276-281 solid roller,12.1.1 comp, and used to run the Victor with a blended adapter but now sport a t-ram and two 650ish billet carbs. Easy 9's and totally street able even on 91 pump gas but I race it on VP-101 unleaded and 18+ years later and a couple of rebuilds, it's still going strong and still uses the same 727 trans, 4.10's and a 22 year old 8" vert.............

Nice ,9 second quarter? Whats your car wiegh?
Got any idea on the horsepower? I have everything but the rods and cam for that build!
Thats what I'm leaning toward.

I have not try that long of a stroke in a low deck, I have used 4.300 stroker on several 400 blocks with good results with both 6.800 and 6.700 long BB Chevy type rods
I would not put a 4.350 stroke or longer stroke crank in low deck block due to the piston skirts hanging out of the bottom of the bores with a 6.700 or longer rod
You might try that longer stroke with a shorter rod in it though

Been an easy 9.79 @ 135+ in 2012 off the trailer running a bit lean and 2 years ago it went a 6.15 @ 112+ in the 1/8 w/a crappy 1.40 60 but then went back 2 weeks later and went a 1.34 w/tubes in the QTP's but lifted due to just a roll bar so that would of been a 6.0 something had I stayed in it. It will go 5.99 or better or it's for sale......Roughly 3050lbs or close to that.....

Sure, we used to build a lot of 451 engines 20 years ago but there is no point in doing that much machine work on a stock 440 crankshaft these days. Just buy a new crank from Molnar or SCAT and be done with it.

True I have the crank and pistons, but for what it cost for machine work I could probably by a crank . Do you remember what block mod you did I remember there was some grinding that had to be done for crank throw clearance?
If you have any info that would be great. Skip White in Tennessee sells complete kits for Ford and chevy that may even be the way to go.