Stroker kit- Eagle 520 or 440Source 512?

Street/strip car- How are the quality/parts of the 440 Source stroker kits? Would the Eagle stroker kits be a better bet? The Eagle kit appears CHEAPER than the 440 source kit...?
On a 76 and newer block is the billet caps/main stud girdle necessary for a street/strip hydraulic cam stroker to live?
Never done a stroked RB.....

My 2 cents
In my stock stroke 440 i have an eagle crank . Been running nearly 10 years , daily driver and bracket raced . 5 or 6 thousand miles a year . No problems , had factory caps .
New motor has 440 source 4.25 stroker kit . I did fit their billet caps on thus one for a bit more strength . Only running since January. No issues at this time . Quite happy with results .
Both brands will work , is there better ? Yep i am sure . Bang for buck ? Definately got that .
440 is a 78 block , 505 may be also a 78 .

Tex

Molnar all the way. I like the 4.25 stroke crank, 2.20 rod journal with 7.1" Molnar rod.

I did convert to studs in the mains but didn't do aftermarket caps.

Lots of hard sreet miles and dragstrip passes.

What is the stroke and rod journal size and rod type on the Eagle kit?
The reason I'm asking that is for the clearances on the rods to the block and how much grinding you will need to do to clear the possibly longer stroke on the 520 C.I. kit, especially if it has the stock Mopar rod journal sizes
I like the 4.250 and 4.300 stroke in both 400 and 440 blocks with BB Chevy rod journal sizes(2.200) I have built several other stroker motors with the stock Mopar rod journal sizes with both 4.375 and 4.500 stroke, never again with those rod journal sizes

Building my 512 now... Molnar Crank and Rods, Icon pistons. better quality for just a few dollars more than the 440source stuff (although I did go with a 440source girdle and billet mains)

As far as quality they are decent! Just need to watch the taper and the journals

If you are starting with a good 440 block then I'd pick a 4.25 stroke crank with 2.20 rod journals. Then go with either a 6.800 or 7.100 long BB Chevy rod depending on piston selection. I'd keep the bore size as small as possible just to keep the wall thickness up and to allow for future rebuilds. But sometimes you can do it all at the same time without going to a custom piston so you just have to sit down and figure it out. Don't forget that you need to know what cylinder head you are going to run in order to figure out the compression ratio that you want. Once you know what you want then you can shop for a kit or buy the parts separate.

Several of the FAST/Supercar guys run the 520(4.375 stroke) combos. There is hardly any additional clearancing needed over the 505(4.25 stroke) combo.
Depending on exactly what you're looking to build, off the shelf pistons are available for either.

First decide if you want the 4.25 or 4.375 kit. Both eagle or source kit are gonna be comparable in my opinion.
With a standard port head I don't see any benefit to an extra 15 cubes between the two for more rod angle and more clearance issues. But either kit would be fine.

A 4.15 Eagle crank has done well for me. Steel caps and studs on a 400 block. Just under 600 HP and run hard on the road track.

As far as brand of crank, I would be OK with either. Also I would/did have it thoroughly checked by a skilled machinist before using it.

As far as stroke... pick based on your goals and the rest of the combo. Heads? Cam? Power goal? RPM? Torque/drivability?

Block mods depend partly on answers to above questions. In my case, I am pushing the stock block as hard as I want at ~600 HP. I would upgrade the block if I want more HP & RPM.

Mine didn't require clearancing at all. The closest part was the oil pump pickup boss and I had right at .060 as I recall.

I use the 440Source 4.15 stroker kit for my 493. I also use the billet steel main caps and ARP studs. Had the block lined bored of course with new caps and the kit included the stock lenth rods and 440Source dished pistons for 10.6 comp with the EZ head. It has nice .045 quench and is fine on 92 pump. Been in my car together since 2011 and its a street car I drive alot in the summer and race maybe once or twice a year. Its been great as I had her out for a cruise today since it was nice weather today. Ron

try ohio crank,they sell good stroker kits

I don't have the heads I want to run yet either, so I would figure out what I want and order accordingly....
I have a 1976 block, actually a couple. I was looking at a 440Source kit- 512ci with 2.2 Chevy journal sizes, trying for a little over 10:1 static with aluminum heads and a hydraulic flat tappet cam at this point. I know the CNC Stealth heads say they flow decent numbers but my buddy with a flow bench doesnt think so?! Trick flow heads too..?
It's a 3600ish pound street car with a 727 and 4.10 gears, I might throw 3.23 or 3.55 gears in once I swap though. 12.50 rear tires and leaf springs.

I think the 512 would be plenty of cubes for that combo. A torque monster. I think you will like 3.23 or at most 3.55 gears.

for what it's worth my dad used the 440 source stock stroke rotating assembly and heads, all clearances were great and it's holding up very well

440 Source are Mopar people. That gives them the edge for me. Look at Eagle's website. Is that someone you want to buy Mopar parts from?

Stock offset ground factory forged here 15+ HARD ass years and if you removed those chokes on top of the carbs, I'd bet it would/should breath better...........nice ride...........

I bought the 512 440source 4.25 kit with the 2.2 journals,
at .030 I believe that makes mine a 505?
Other than the 7.1 rods needing some work, I'm very happy with it.
A real beast!

I stillllllll haven't found out the rod journal size!!? Stroke is 4.375
Eagle kit is 21203030

One of my friends bought a 440Source 4.25" stroke crank for his bracket Challenger. They are rebuilding the engine now since he said the crank oiling holes were drilled wrong. I don't know the details, but it might be worth checking if you have one of their cranks.

My machinist/engine builder down in Tampa said he had a SCAT crank that had machine work as good as the Bryant cranks he prefers. I'd lean towards a SCAT crank over an Eagle or 440Source based on his experience. $.02

Wow thats really a nice Charger. Another fine red Mopar ! Ron

Thanks Ron!
I'm obviously in love with your 63!

It just doesn't move the way it should. It's a late model low compression 440 with a Comp Cam of some sort and pea shooter exhaust. I want some decent power.

I've learned the hard way lately, we all only live once!!!