I see these industrial engines on ebay and they are built on the Gen7 8.1/496 platform.

https://www.ebay.com/itm/23471275582...Bk9SR9LRjOmBYQ


Last one I looked at was @ 4.350 bore x 4.500 stroke...

Intake and ports look a little small but they are selling complete, intake to oil pan @ approx $1500-$1800.

Even if I toss the heads in the dumpster and use the shortblock as a rebuildable core, I can hang Raylar heads on it and be @ 550+ cubes pretty cheap.

Otherwise Im looking at $2500~ish for Dart 4.500" block and $600 for a 4.5" crank.

Thoughts ???

My understanding is that PSI bought the tooling when Gm discontinued the 8.1 so these should be functionally very similar to that. Gen VII so you can't use earlier cylinder heads on it, Raylar pretty much your only choice as far as I know.

Yeah I currently have a VP 8.1 and was hoping to keep the same platform when I make upgrades so it looks and functions like OEM.

Obviously cubic inches are always the answer... and this looks like a pretty cheap score if I can use the shortblock.
If the Math doesnt shake-out, I will likely just build from scratch on a Dart block and forged crank.

Dart had a head listed for the 8.1. Not sure if they are still making it?

535ci as from PSI. 572ci if you stroke to 4.750".
Yep, it's compatible with gen 7 8.1 platforms. The block is a nice piece with individual piston oil squirters. Can be bored to 4.400". 4.500 crank. Minor grinding will fit a 4.750" crank. Stock shortblock internals from PSI are forged. Though the pistons do not have a large valve relief as most performance pistons. PtoV needs checked going bigger than Raylar 203 cam. The PSI heads are junk for power usage. Designed for BIG torque under 3k rpms. Raylar and Dart heads will bolt right up. Raylar has a new 90mm alum intake out very similar to the LSX intakes.

Good to know.
I saw pictures of the PSI intake and while the 91mm throttle body mount is a plus... the intake ports are terribly small. Nothing like the tall cathedral ports on the stock 8.1.

I think the Raylar heads and cam on a fresh PSI shortblock might be the cats whiskers.

Why not just go the entire Raylar route? They are the de-facto experts of modifying 496 platform and you will probably be ahead of the game when it comes to cost. Especially if you want to upgrade HP and maintain stock appearences.

Larry will tell you to go with a PSI shortblock. He sells them. It's a better than stock block. Also has a bigger bore. 4.350" vs GM 8.1 @ 4.250". Only real downside is that it has 1/2 x13 main cap bolts and no windage tray provision vs GM8.1. GM main cap studs are 12mm and cannot be used on PSI block.

If wanting to run a windage tray setup in a performance PSI 8.8 block you need ARP main studs and align hone accordingly.

This one?

https://www.raylarengineering.com/vo...te-engine.html

Spot on!