73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Performance => Topic started by: krazylunatic on November 08, 2009, 10:46:46 am
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Okay guys, i just bought an 82 pickup with a mildly built 350 motor i guess youd say. Im not much of a chevy guy or an engine guy, I can change my oil and all that and figure some things out but when it comes to internal stuff im lost. Supposedly the truck has a 93 or 94 block, has the same cam that comes in a zz4 crate motor from what I was told. Has double hump heads, 2.02 and 1.60? not totally sure what the numbers mean, exhaust and and intake size? idk. They have some port work done. Has an edelbrock torker intake and an edelbrock 650cfm carb and headers. I was told it should make around 375 at the crank? idk, just want to change some things and make it a little faster but not sure where to start. What would u guys consider the weak link? I was told for the cam I had those heads would be fine. Im wanting to change cams to something with a more aggressive idle. The cam in it is okay, but has the kinda idle where it sounds like its about to die, I want a cam where it sounds like its about to blow up, if that makes sense? Not wanting to spend a ton, maybe a different cam and then in the future some better heads. any little things i can change up to add some horsepower? roller rockers etc?
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Being a 1982 it may have a highway rear end gear. Look into what you have. A simple gear change will really wake that up.
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what would be good gear? im use to fords, ive tried to find out what gearing it has but dont know how. guy said 2.73's i believe. Was thinking of getting 3.55s, keep the rpms down for highway cruising, anyone know of better cam with a faster idle, or sounding idle, not sure how to word what im looking for
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Either a 3.42 or a 3.73 are factory ratio's for GM. There may be others. A 2.73 can be a dog if the engine doesn't have low end. Our trucks are rather heavy and torque is needed down low with a highway gear.
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how do i tell if ive an 8.2 or 8.5 rear, its a 10 bolt
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how do i tell if ive an 8.2 or 8.5 rear, its a 10 bolt
If it's original, you have an 8.5".
I would ditch the Torker intake. Based on what I know, they serve no purpose what-so-ever. If the engine build warrants a single plane then a Victor Jr. or Super Victor would be the way to go. But for your purposes, a Performer RPM or Performer RPM air-gap (or equivalent) would be a much better choice. Losing the torker intake and dialing in your fuel and timing should definitely increase torque throughout the powerband. That's where I would start as far as the engine is concerned.
BTW 2.02" and 1.60" is the size of the intake and exhuast valves (respectively).
If you are interested in building up your engine, I would recommend the following book: http://www.amazon.com/Build-Chevy-Small-Blocks-Budget-Performance/dp/1932494847/ref=sr_1_1?ie=UTF8&s=books&qid=1257711570&sr=8-1
Here is a good article on specing a cam (written by the same guy that wrote the book above): http://www.popularhotrodding.com/tech/0607phr_camshaft_basics/index.html
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for the rear match it up with one of these
http://coloradok5.com/axleguide.shtml
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Maybe you should talk to a custom cam grinder. Tell them what you got and they'll cut you a cam that'll use the parts you got or have access to. Either that or look through the SummitRacing site and come back here with part#/specs, run the cams by the guys on here...they could probably tell you which would give you the sound and performance you want.
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A couple of obvious things to look at first before diving into a cam swap have already been mentioned:
1. Confirm your rear end ratio first. A 2.73 would definitely be a killer on performance. I had a 2.76 ratio 12 bolt and that sucked.
2. Your intake. The Torker, to me, seems like a screw-up that was put into the market before they had today's technology to really design manifolds better. I'd go with a Performer Air-Gap. RPM or not is up to you. With the 2.02/1.60 heads and what might be a somewhat healthy cam, you may want the RPM model but then I'd definitely look at a 3.73 gear ratio. 3.42 minimum. All of those parts don't make for much low-end under say 2500 RPM so the gears help keep your RPM in it's healthy range.
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Gears, Gears, Gears!!
I bought a truck (82 3/4 ton 4x4 chevy) that had a really well build engine, tons of money into it, but he guy never changed the gears, then added 36in tires. Off the line it was a complete dog, it didn't wake up till you hit around 55-60 MPH. It totally sucked in town.
The engine make tons of HP, but it could not get to it due to the gears.
So, start with the gears like the others said.