73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Zac.richardson1 on October 31, 2016, 03:39:09 pm
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This is my first post and I was wondering about a 383 for my 85 GMC Sierra 4wd. First off I'm wondering how hard it'll be to build a 383 stroker. I'm wanting it to push 400hp minimum and be as cost efficient as possible. I'm planning on getting my block bored over and buying the Summit racing 383 kit. The kit for the 383 stroker kit says the bore is 4.030, is that on the pistons? Would the block have to be bored over 4.040 or 4.035 to fit the pistons? I could be crazy wrong I really have no idea what I'm talking about. (Here's the kit: https://m.summitracing.com/parts/ses-3483002050?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-summit-racing&gclid=COuFjbfwhdACFYY7gQodtVAJYQ). What kind of heads would I need to get and what else would I need? Where do all the ratios I've been reading about come in and what ratios could I expect out of my motor. I've been researching for about a week now and I kept finding myself here so I figured I'd make a post and see if I couldn't get some advice. Thanks
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If you are looking at cost effectiveness then why a stroker? You will be paying a machine shop to do a lot of the work and may need to clearance grind. There will be a lot of disassemble/reassemble for test fir and measuring.
The kit for the 383 stroker kit says the bore is 4.030, is that on the pistons? Would the block have to be bored over 4.040 or 4.035 to fit the pistons? I could be crazy wrong I really have no idea what I'm talking about.
The bore is the hole in the block. Your pistons would be the size of the bore. You need to check your piston to wall clearance and your ring end gaps before you install them.
What kind of heads would I need to get and what else would I need? Where do all the ratios I've been reading about come in and what ratios could I expect out of my motor. I've been researching for about a week now and I kept finding myself here so I figured I'd make a post and see if I couldn't get some advice. Thanks
Ratio's out of your motor? Are you talking about compression ratio? Picking cylinder heads would be based on what intake you are running, what you want your compression ratio to be, valve lift, etc. Don't make the mistake of putting a ton of money into the engine and not factoring in the entire powertrain. You need to consider your final drive ratios, transmission speeds, tire size, type of driving you will be doing etc. Look at the big picture because this is where most mess up royally and flush a lot of $ down the drain that would be much more well spent in other areas to increase overall performance.
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What would you suggest?
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I'm expecting to pay around 2500 on the motor but if there's something else I should work on to make it a 450hp truck then tell me. Thanks
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Maybe shed a little more light on your end goal. Towing? Mud truck? Rock crawler? Mostly street but will push you back in the seat?
Realistically, a build for low end torque would be more beneficial for most trucks than a high horsepower engine that makes 400+ hp at 6,000 rpm - just my two-cents.
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I'm looking for it to be mostly street to be honest. The body on the truck is in too good of shape to play in and I was really wanting to daily drive it then to be jumping rocks inbetween mud holes
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I wouldn't mind hitting a trail in it, although the trail would be nothing I would have to worry about getting stuck in. I'm thinking I would like it to push you to the back of the seat more than anything. Alittle towing ability would be nice but I'm mainly looking for the power
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Not to steer you away from a 383 build, you should definitely consider all things on an engine build.
You posted about a 6" lift in another thread. How about gearing? 1/2 ton or 3/4 ton? Swapping to deeper gears at some point? Auto or manual?
There are several posts on torque builds here for a SBC. Here is one to look through, which has several additional links http://forum.73-87chevytrucks.com/smforum/index.php?topic=32711.msg277566#msg277566 (http://forum.73-87chevytrucks.com/smforum/index.php?topic=32711.msg277566#msg277566)
Whichever route you go, the remainder of the truck will need to be able to match the engine (as Vile commented on). It's likely that you'll be very unhappy with a high revving, high RPM engine in a truck with a high ratio (i.e., 3.08:1) gears and stock auto transmission convertor.
The devil is in the details and there are a lot of particulars that can make for a grin or a grimace whenever you mash the foot feed...
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It's a 1/2ton automatic. Not too sure on the gearing but I think it's geared 3.08 like you said but I would be ok with a ton of low end torque as long as I feel an overall improvement in the trucks ability to pull itself. I live on the mountain and it's alittle slow pulling up it. I just don't know where to start
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It's a 1/2ton automatic. Not too sure on the gearing but I think it's geared 3.08 like you said but I would be ok with a ton of low end torque as long as I feel an overall improvement in the trucks ability to pull itself. I live on the mountain and it's alittle slow pulling up it. I just don't know where to start
When you quote desired horsepower, you're focused on the wrong thing. You race horsepower, but you drive torgue. For a street machine, torque is where it's at.
The guys with the 500hp Chevelle's and Hemi Cuda's found this out when they ran into a 360 hp Buick GSX back in the day (1970). 510 ftlb of torque in the Buick would win the 1/8th mile stoplight to stoplight drags every time, and with A/C to boot, which the others didn't offer. I know. I was there. Nobody could touch that GSX.
You can save yourself a ton of money by either re-camming your current engine, or re-camming a new 350/260 crate engine with something like the 12-235-2 or 12-300-4 (in the mountains, I would go 12-300-4, but that's me). People here and on the other squarebody forums have used both and love them. Put headers and a dual-plane manifold on it, then swap to 3.73 gears, and you can spin both rear tires (assuming a G80), without brake torquing, just by punching it.
Stick with the stock rpm torque converter, maybe move the WOT shift points down one notch with a weight substitution on the governor, and you've got a brand new motor and 400+ lb ft of torque for a couple thousand bucks.
You don't need any more displacement. You aren't even beginning to scratch the surface on what the 350 can do.
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I run around with a 355 with vortec heads, performer vortec manifold with a 268H comp cam.
Cheap-O headers with dual exhaust and 2 1/2 turbo mufflers, A Quadrajet, 2000 B&M stall converter with 35" tires and 4:10 gears in my 74K5.
She scoots along quite nicely.
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Someone suggested I get a 5.3 out of a newer truck because they are better on gas, and more bang for my buck. How does that idea sound?
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A lot more to a 5.3 swap versus replacing a SBC with a SBC.
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So for my 1/2 ton truck with now a 4spd automatic (planing on putting a manual transmission in it) with 3.08 gears and a 6 inch lift with 35s (eventually 38s) what work should I do to the motor to get it as bad as possible. I'm wanting something that can carry around the truck easily and at the same time can tow/spin tires. What is the cheapest route and would it be a 383 or something else like a 355 or 5.3? What are the benifits of the different options? Gas mileage? Horsepower? FtIbs?
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With a 3.08 gears and 35" tires, I'd regear to 4.10 before considering a motor swap. That "...can carry around the truck easily...and can tow...".
If you are going to 38" tires anyway, I'd go straight to a Dana 60 front and a 14 bolt full floater rear and geared to 4.56. Of course, those axles have 8 lugs so new rims/tires would be necessary.
I like Blazer 74's sbc w/ Vortecs, etc.
My $.02.
'
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If you really want to daily drive it, keep the 700R4 with the lock-up torque converter or find a manual tranny with over drive. What's the predominant mph where you'll be driving it? I'd run 4.56 or lower gears depending on mph you want to run with 38" tires.
I would figure out tire size and gearing first. I honestly would run 35's, but it's your truck. Make a few changes to beef your 700R4. Buy vortec heads and a roller cam that pulls from idle to 4500-5000 RPM. If you go with the bigger is better theory, you'll most likely have poor driveability. Stay with a 600 cfm carb, get some shorty headers and dual exhaust. Some electric radiator fans will help MPG. You can switch to a manual tranny later if you really want to. There's a nice vortec headed engine with roller cam for about $2000, then add a better cam that these other guys recommend, if you don't want to put the parts on yours. Like Vile said, if you don't plan your package to work together, you'll be unhappy.