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Discussion Starter #1
Hey all,
My '94 K1500 needs it's engine replaced. It's a wheezy 350 TBI with the lousy factory cam. No guts, hardly making any torque, especially with 3.73 gears, and 35" tires and a 6" lift. I have a Vortec 350 four bolt main one piece crank block with 1.94/1.60 iron Vortec heads, and need a maximum high and flat torque curve, up to 4500-5000 RPM, and no interest in going beyond this RPM. It's an 880 block, so I can't go 383; the cylinders are shortened by 3/8" on these blocks, and I know I will be asking for trouble with a stroker crank and the pistons sticking too far out the bottom. SO, I want to go TPI, with the large bore Vortec base manifold ($400), enlarged SLP runners ($300), a ported 58mm TPI plenum ($140), TPI harness, TPI ECM with a torque program probably from PCM for less, bigger injectors, fuel rails, etc. 0.030" over flat top pistons with +/- 10:1 CR ($250), forged floater 6" rods ($150), Vortec heads machined for max lift, new electro-polished springs, new stainless steel valves, 1.6:1 roller tips, and required machine work. The crank needs nothing. I have read some online articles, and some folks ended up with way over 400 lb.ft of torque with the right cam and a similar set up with 6" rods. I want to be at 425 to 450 lb/ft. at the crank and that should move this beast pretty well. If I can get even more lb/ft, that would be optimal! If anyone could recommend any tips in acheiving this goal, I would be appreciative.:usa:
 

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Discussion Starter #3
BS huh? Go and measure the cylinder length, top of the deck to the very bottom edge on a 880 block with a 010, 327 or any other sbc. The cylinders are shorter. Would YOU make a stroker out of a block with shorter cylinders, and if so WHY, if you had a choice?
 

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For the first time in 40 years, I don't have a SBC laying around.

So, you go ahead and post pictures of this phenomenon. You'll be the first to break the story.

By the way, this needs to be from the crank main bearing center. No other reference point will be a proper datum.
 

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IMO the biggest thing you need to be careful with is cam selection. If you want max torque you can **** that up real quickly by going too big.

GM uses that same block for the fast burn 385 and ZZ383 so I dunno about the short cylinder thing.
 

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Discussion Starter #6
Alternate path after doing some decision making, talking to Comp Cams and my machinist. It's getting a 08-501-8 cam (as per the Comp Cam man: 212/218 .488/.495 112 deg LSA, 1200-5200 RPM and plenty of vacuum), dual plane air gap, adapter plate and bored out TB, increased fuel pressure and chip tune, flat tops, staying with the stock 5.7" forged rods, full valve job, beehive springs, bored with a plate, and balanced rotating assy. I have seen photos of the 880 block in 383 configuration, but that was on the interwebz; my momma told me not to believe everything on the interwebz! May as well do what I can with what I have and the cam recommendation. It may take me a good while to complete, but I will let you all know. Heads, block are getting soaked, and crank is getting polished. Some parts have been ordered. Still need to get to the strip with my signature vehicle this spring and fill in some blanks.
 

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Discussion Starter #8
Geardo, yes, I did abandon it. I know it would have been an increase in torque. I just cant justify the $$$ difference between a high rise dual plane intake with an adapter plate, and a lightly opened up TB base with more fuel PSI and a TBI chip vs. a nearly $500 Vortec TPI base, TPI runners, injectors, ECU and wiring, TPI specific hardware, time needed to research and hunt down all the necessary parts. I don't think I will miss NOT having an extra 30-50 LB/FT of torque where I can save at least $1500 by sticking with TBI. If I would have gone 383 vortec with the high rise dual plane TBI intake, I think I would match or maybe surpass a TPI 350 in torque, and possibly still save about $1000. My truck isn't a pristine 4X4, nor am I going to lift the hood much to show others what I have. I will be towing other vehicles and junk with a dual axle trailer, and I live in an area with a lot of canyons and mountains. I roll on 35" tires with 3.73 gears and a NV4500 5 speed. I'm hoping the votec head technology will give me the midrange I desire with the cam I chose. When I'm done, I'll happily share photos and possibly dyno results. Still working on it slowly but progressively; I should be able to drop it into the truck around April/May 2014
 

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Discussion Starter #10
Who wants to go broke filling up the fuel tank constantly on a big block truck, even with TBI? I figure the 355 Vortec TBI set up I'm making will not only provide a big boost in power, but maybe even a slight boost in fuel mileage. I'm getting 13 to 14 MPG loaded, empty, highway or town for fuel mileage. If I can get above 15 MPG or better, I'll be happy. I don't see 14 MPG with a 454 at all, plus even more engine weight to haul around. I also know many of them short of a 454 SS were complete TURDS in the way of power.
 
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