JaniH

Thats ok! No need for complete engine. What i need is a forged crank.

SB

iTrader: (1)

99% positive it is a professional Products intake. They(PP intakes) look like the dart's but they added rear water water bungs. They also had polished intake part #'s.

Just as a note, Professional Products was absorbed into the company Pro-Comp. Pro-Comp, because of it's super ****ty name over the years from committing fraud copying others parts, also name infringements, and making some really schitty parts, became Speedmaster,Inc several years ago.

JaniH

I also have the mercruiser magnum original aluminun dual-plane, with bronze water crossover. Could cut the divider or use open spacer.

MILD THUNDER

iTrader: (3)

is that the chinese intake articfriends smitty tested back to back against the edelbrock victor jr? I wanna say he said it outperformed the victor?

SB

iTrader: (1)

Yes it is the same. Smitty's had port injector bungs on it for fuel injection, but otherwise the same.

other tests by other people over the years has also shown it close or jjust ahead of the vic jr and/or dart. Just meaning just a few hp typically.

remember, as I mentioned it is really a copy of the Dart with addition of rear coolant holes and one in frt lower of t-stat boss.

if someone is to use one, I would strongly suggest making sure the ports line up, dist gear lines up when everything is installed, and the the sealing surfaces are straight, true, and not machined too far. I guess same can be said for any man's stuff, but this company really wasn't spending a bunch of time on quality control. I got one of their SBC intakes way back when and the EGR(exhaust heat) port didn't line up. Would have leaked into the lifter valley. Sent that back and never dealt with them again. Other co's intakes aren't brutally expensive.

Anyway the OP wasn;t sure what he had for an intake and I gave him the answer with a quick interesting history of it.

JaniH

Ok, things are getting clear. Current parts listed.
-gm 4bolt, 030 over, 461cid, compression ratio 10:1
-speed pro forged l2349f pistons
-scat I-beam 7/16" rods
-gm 039 nodular cast crank​​​​​​
-dart iron eagle 308cc heads. Stainless steel valves.
-crane gold 1.7 roller rockers
-intake manifold, merc 502 stock aluminum dual-plane or that professional products single-plane.
-exhaust stainless marine with 3" taller risers
-camshaft ??????

Those darts or summits have dual springs for flat tappet cam and pushrods that came with the heads are, 8pc comp cams 7757, 9.5" .080 the last 8pc has marking k9803. Flat tappet cam would be cost effective.





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sutphen 30

one thats listed at the bottom of the page.

I'd say you couldn't go wrong w/ the crane 731 or what ever its listed as now.226/234

f_inscreenname

You gonna do all that (imho) you should have done a stroker 496.

JaniH

Have decided to go with hyd flat tappet cam because i allready have all the valvetrain parts for that, what you think about comp xe274 0.050 230/236, lobe 110. It is almost identical to the old merc 454 440hp cyclone cam. My heads flow better than those cyclones and i have 10 to 1 compression against the cyclones 8.5 to 1. My dynamic compression would be 8.37 with the xe274. Hoping to get in 470-500hp.

sutphen 30

good choice,I used cam motion cams version of that,had great power range,very flat tq curve,my heads were ported ovals from gm.