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questions/opinions on small block engine combo

Posted By: superbyrd

questions/opinions on small block engine combo - 03/24/11 12:46 PM

i have slowly but surely been gathering parts for my 84 swb step side project,and have a few questions about my projected engine combination. the rest of the truck layout will be a new venture 3500 5-speed trans and 3.55 suregrip rear. that out of the way,here goes...
i have a 73 340, already bored .030 over,.010/.010 turned stock crank and rods,i have a new set of old (box dated OCT.1986 lol) badger cast 10.3 to 1 2-valve relief pistons,new box stock edelbrock performer RPM heads,performer RPM intake, i plan to use a comp cams XE274 cam, topped with a holley 670 street avenger carb and mopar orange box ignition kit. exhaust will be handled by a set of polished stainless equal length shorty headers designed for 94-up truck/dakota/durango.
these are all parts i already have on hand,and my questions are, with these pistons sitting .028 above the deck,will i have clearances issues with the eddy heads,with this cam? will i have to notch the pistons for clearance? i will be using .039 thick fel-pro blue head gaskets. also,will my compression ratio be a wee-bit high with the eddy 70cc or so combustion chamber and these 10.3 to 1 pistons?
and lastly,what will i have to do about a flywheel? will i have to have a specific 340 flywheel or will something else work? i am going to send the entire recipicating assembly out to be balanced when i figure out a flywheel set-up.
this may be overkill for a daily-driver,street pickup,that i plan on driving to the nats (a 1000 mile round trip) and various other shows.hoping for a solid 350HP out of this combo. i have no plans of racing the truck,just driving and enjoying it.
any thoughts and advice would be great.
i have always built big-block chryslers,so this will be my first hot-rod small block build.
Posted By: DaytonaTurbo

Re: questions/opinions on small block engine combo - 03/24/11 01:05 PM

If the pistons already have valve reliefs in them, you shouldn't have any problems there. The xe274 isn't that crazy of a cam.

Make sure you check out your piston to head clearance. Are those heads closed chambered? Because .039 gasket - .028 above deck pistons = .011 piston to head clearance, much less than the generally recommended minimum of .035 for a street engine. Now if that's how far a piston dome sticks up or if they're open chamber heads you have a bit of room to play. Otherwise it's a thicker head gasket needed.
Posted By: superbyrd

Re: questions/opinions on small block engine combo - 03/25/11 11:09 AM

anyone else........
Posted By: patrick

Re: questions/opinions on small block engine combo - 03/25/11 01:17 PM

the fel-pro gaskets in the kits are usually .054" thick, if your heads are closed chambered, and the pistons actually measure closer to .019" out of the hole or less when assembled, you're fine. otherwise you might need to skim a skoash off the tops of the pistons for adequate piston to head clearance.

compression will be fine for pump premium. check and make sure those shorty headers will fit without interference to the firewall.

good luck with the NVG 3500, they aren't the strongest trans.....biggest engine chrysler put them behind was the 318 magnum, biggest engine anyone put them behind was the 210HP TBI chev 350's...they're rated for 340 ft-lbs of torque
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