How Big can a 5.2 get?

high.rev.trev said
Hi. Your in Finland ?? 2 options: 1 isn't a 'Magnum' Block but Scrounge around for a wornout 240 or 250hp Chrysler Marine Sterndrive engine: its a thick bore/casting H/duty Block with ALL the goodies ( & I mean ALL the factory H/duty goodies: bushed/floating small end ",Truck/Industrial Rods High Pressure oilpump, 273ci Commando Single Plane 4bbl Intake , big 4bbl AFB, STEEL crank, etc etc) OR if some Intl freight isn't out if your Budget there's an Engineering Business in Australia that makes Custom overbore size pistons with pins & rings supplied.
JP Engineering try google jpengineering.com or jpengineering.co.au I know the owner Laurie - Tell him Trev from NZ sent you. He'll make you Std +080" block savers or any feasable overbore req.
I read in a Hotrod mag Magmun blocks didn't like much over +030"_ +040 without sonic testing & your pushing it: Suggest a Welded up offset ground Stroker Crank done locally with a Custom Compression height piston to match: +.060" 318 takes you to 327cubes, did 1 with smooth flattops: not valve reliefs & pocket ported heads & that was a Stormer , IF you find an ex Chrysler Marine they've also got a high torque H/duty Starter Motor, which is a cheap way to get something to swing the project over + save those Intl EBay type Shipping costs :-/
Goodluck .Trev

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Yes I live in cold Finland, near russian border.
Not much marine engines here to use, I believe there hasnt been so many and whats left nowadays are rotten.
This Magnum is 1993 from a Grand Cherokee and the block is in great shape, got it bored .030 over and cant think how it wouldnt manage that.

high.rev.trev said
Semi-delete that last reply of mine: I replied to a muchvEarlier post of yours...but, how high are you going to spin that. 318 ?? - that's a high Rev midrange torque manifold like hovering around 4'500 rpm constant like circle track. + things can't be TOO expensive in Finland if you've got KB pistons & proflow injection. ,( not as tough as here in NZ, we pay near 45% extra to $US with exch rate + the high cost of Shipping 9,000+ miles, then there's the +15% GST which then incures another $176+ flagfall in customs' creative surcharges.
Cheers anyway. T

Well, im thinking the engine should easily rev to 6000 and with my gears, Im in 2700-2900 range at highway. The intake is a bit overkill, I know. But thats what edelbrock has decided to offer to this set. There isnt much options for mopar EFI intakes, in fact super victor is the only one :D
But in MPI the manifold has to provide only air, not atomized fuel so maybe it isnt the same as with carbs? Perhaps someone can lighten this a bit??

We have to pay 24% tax from everything including shipping, so 375usd KB pistons cost me 589usd and 1895usd fuel injection costs 2644usd when delivered.
But, ive decided to do this once, and dot it properly and when its done its done.
I can divide the cost to 10 year or 15 year period and then it isnt so much after all... You know, theres many ways to cheat your mind.
:rofl: