Anybody done one of these?

Pro's/Con's?

Not that kit. Question would be what is the application for. Also What heads are you planning on using? It's easy to over cube the efficiency of the heads. The 4.250 stroke with the 7.100 rod fits really nice and horse power can be made in other area's than the additional stroke.

In my extremely less than novice opinion, a 4.5" arm in a stock block would put a lot of stress on it (especially a 440 that has a weaker bottom end than a 400). I'd think for a low rev motor it would be a nice kit. You'd want to under head it in that case.

Good for a truck, not a good race motor in a stock block.

Whats the exact engine specs and application?

For a 440 RB block: 4.500" stroke. 7.1" rods. I'm sorta considering one. I would need the extra wide flange #3 main bearing (for my later block) and I wanted file fit rings

I built a 535, 4.5 stroke, 4.350 bore. It made a ton of torque with 906 ported heads. It can be built into a great street motor because you can shift at 5400 or so and maybe less for best performance. I was shifting at 5700 with a 590 cam and I may have been over revving it. The nice thing about that many cubes is the ability of running a very tight converter and a low (3.23?) rear gear and it will still fly. The key to making it live is keep the revs way down and be conservative on the tune. They also make great bracket motors if you want a very low rpm reliable deal. I believe the torque peak using the McFarland formula would be about 3900 rpm. This is not a motor to push over 650 hp, or big port heads.

I have a 4.25 crank with the 2.20 BB Chevy Rod size and journals.

It's pretty close on the oil pump pickup (within .050) and it still easily clears the bottom of the bores with no issues.

I put together my own "kit" using Molnar crank, 7.1" rods and Mahle pistons. It balanced really nicely with just a little weight being removed from the crank. It was also cheaper than the source kit and utilized, IMO, better rods and pistons.

The Molnar stuff is very nice and dropped in with no fuss!

I didn't use 440source rods, I run GRP rods. But I used 440source pistons and crank. It runs hi 5's in the 1/8th. It's a 77 440 block with a 1/2 fill and main studs. Indy -1, roller cam and Sequential EFI

Cons ... external oil pickup lines because the stroke is too long to clear an internal pickup tube.

If the crank doesn't have the extra wide flange you don't need them , the normal flange fits that block just fine ...

and good luck finding them if they are anything like the low decks ... not made anymore.

Thanks double R, its been on hold for quite awhile but I will check into that & see what I need to do/not do/change. it is a pricey deal & I did already grab a bolt in pickup for external oiling that 'source had on (clearance) sale for dirt cheap (not a big start but every bit helps) & the one guys' post on the cheaper Molnar crank/Mahle pistons deal sounds worth checking into especially since I wont be racing it, just an occaisional street blast

Even if you have the wide flange crank ... which I doubt it is ... you can use a narrow flange bearing , it won't hurt a thing.

the block I have is a 74 with the wider flanges. it'd be the 'source kit (their crank). iirc I asked em about the later bearings which were extra. just not sure at the moment if 100 extra cubes is worth a 2K (& then some) $$$ outlay

You need to consider the difference in costs between the stroker kit, and the parts/machine work required just to reuse your old parts, then the cost of the stroker kit looks alot better. The costs of all the parts have been going up, back when I bought my stroker kits they were under $2K.

Woops, guess I had already responded..

Haven't done a 540 but we have done 3 of the 440 source 512 RB kits. I like everything about it except I wish the rings were a little racier. We are gonna try the stealth heads on the one we are doing now.