Thread: been wondering about my engine. need some advice

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Originally Posted by BIG-JIM

I have been building the car of mine for what seem like forever. I'll get the the point. I decoded my SBC the other day and it wasn't good. As it turns out not all 350's are the same. Seems I have a 1974 350 with 333882 heads auto and a 2 brl carb it produces a freakishly low 145 hourespower Stock. I did rebuild it several years ago to drop into my 40 but I sold that car and kept the engine for my 34 build. I'm not sure what size bump stick is in it. I remember telling the guy at the counter to order me one a couple notches above stock. I moved twice since then and lost the card telling me what it is. I did also upgrade to .030 over pistons, block hugger headers and an edelbrock duel carb setup (duel 500 cfm). I'd hate to rip it all apart again but I wouldn't be apposed to dropping some 041 or 186 heads on it if I thought it would be worth it. AS it stands now I think I'm over carberated. Any advice? I don't want a fire breathing monster or anything like that 300-325 ish??? would work for me.

Hello Jim, let me see if I can help you put a plan together. An inventory of the parts you have on hand leaves me dubious as to whether or not you have the basis for a good engine build. The block is a flat tappet, 2-piece rear main seal unit that has little or no value on the open market. The heads are cast iron 76cc chamber smogger units, again, best used as a doorstop. The cam is unknown and it's compatibility with an unknown static compression ratio leaves us in question. The block hugger headers are only a little better than a common cast iron stock exhaust manifold. Anyone expecting a power increase from headers would do well to read up about long-tube headers. Do we know anything about the pistons? Cast, cast hypereutectic or forged? What is the compression distance (centerline of the wrist pin to the piston deck ?) (1.560" on a quality piston) What is the crown volume? Eyebrows, dish, pop-up? What is the piston deck height (distance from the piston deck to the block deck with the piston at top dead center) ?

There is nothing wrong with running 2 500's on the street, but you have painted yourself into a corner with the intake manifold. It will only fit 1955 to 1986 Gen I heads, eliminating using a Vortec head or moving on to a Gen 2 or 3 motor. But actually, at this point, I might cut my losses and find a good-running LS1 motor, using the EFI with an aftermarket wiring harness. Here's an example....
01 02 03 Chevrolet Corvette Engine 5 7L LS1 Autogator Warranty | eBay

A good set of aluminum heads for the Gen I motor will cost about $1100 out of the box, ready to bolt on and run. (Pro-Filer 23 degree, 185cc intake runner heads), plus all the other work and money it would take to make a nice running 350 that would produce the 300 to 325 horsepower you're looking for. Early production fuelie heads will make that power easily, but you'll have more money in them, getting them to the point that they will operate the way you want them to, than you might have in a brand new set of aluminum heads that will surpass those hp figures easily. Early camel-hump production heads, such as 3782461....64-66...327 will have no accessory holes drilled and tapped on the front face for accessories, so you would have to rig up something off the exhaust bolt holes to hold the alternator and any other accessories on the motor.

There is nothing wrong with running 2 500's on the street, but you have painted yourself into a corner with the intake manifold. It will only fit 1955 to 1986 Gen I heads, eliminating using a Vortec head or moving on to a Gen 2 or 3 motor. But actually, at this point, I might cut my losses and find a good-running LS1 motor, using the EFI with an aftermarket wiring harness. Here's an example....
http://www.ebay.com/itm/01-02-03-CHE...-/121745268928

If you want to hang with the Gen I motor, while you're finding answers to the questions I asked, please do a little reading for us.....

http://www.crankshaftcoalition.com/w..._compatibility

http://www.crankshaftcoalition.com/w...ips_and_tricks

http://www.crankshaftcoalition.com/w...op_dead_center

http://www.crankshaftcoalition.com/w...ck_deck_height

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