How to spend $1500 on engine upgrades

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84 Shorty

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1984
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C10
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350
Rebuild the top end...roller cam set up, heads and intake. This should run around $1500 doing all the work yourself.
 

AzGeo

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The valve springs are junk by now . The EGR intake is a bad thing, needs a "spread bore" 4 bbl, the cam is also a problem . The fact that "current engine condition" would be the FIRST thing to inspect and consider, while talking about $1500 , more power, and a roller cam . HA HA Check out you local "smog laws", and then do a "leak down test" . "A good running motor does NOT leak fluids" .
 

84 Shorty

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The valve springs are junk by now . The EGR intake is a bad thing, needs a "spread bore" 4 bbl, the cam is also a problem . The fact that "current engine condition" would be the FIRST thing to inspect and consider, while talking about $1500 , more power, and a roller cam . HA HA Check out you local "smog laws", and then do a "leak down test" . "A good running motor does NOT leak fluids" .

That list was what I would do to mine if I had $1500
 

4WDKC

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be honest to yourself, do you think you can do the work listed below or even find someone locally to do it correctly? What is the American car market like there can you find used parts for cheap?
1 test compression, post results
2 if 1 is good, new single 3" exhaust to replace stock including y pipe, muffler of choice ( usually cheaper than duals and still flows well.)
3 Ram horns, if you can find them locally for cheap yes, they are better than stock and will save you lots in shipping.
4 4bbl intake manifold of choice ( paint to look stock/ not stand out)
5 600 cfm vac 2nd carb of choice (youre not building a racetrack no need for 750 double pumper manual secondaries)
6 for what you will spend on roller tipped rockers you can buy a new cam and lifters, then need valve springs. Honestly Id put new seals on the valve stems while you are right there.
7 If possible cheap used heads, Id look for TPI heads, they flow about as well as double hump heads and are cheaper. If you cannot find aftermarket.
 

JasperStam

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C20
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350 / 5.7
Thanks again on your ideas. I had a look over with the mechanic totday. Some concerns on leaks here and there. Compression on some cilinders not optimal. Most ideas are good, but if I wanna go in for for the long run, a complete engine rebuild should be considered. Together with a new 4 brl carb, new intake manifold, HEI ignition & labour, I would be looking at 3000 - 3500. Hmmm. *starts counting money*
 

JasperStam

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Engine rebuild = including all new bearings, seals, slightly upgraded cam, lifters valves etc. 2nd hand cilinder heads are realy hard to come by over here. For those who were interested, i’ll post pics of the differential, allthough i dont now how that figures the gear ratio. It rolls on 8.75R16.5 wheels, standard according to the VIN tag inside drivers door. Tires pretty hard to come by.
 

JasperStam

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shiftpro

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Converting to "roller valvetrain" :rolleyes: is cost prohibited and a ridiculous notion...I apologize for them. :confused:

I'm being sarcastic, no need to apologize for me.
 

75gmck25

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5.7
I have a similar setup in my '75 GMC k25, and I'm working on my upgrades.

The most significant OEM weakness of these engines is the poor flowing cylinder heads. You can can change intakes, carbs, exhaust, cam and other items, but it will all be limited by the heads. If you want a more long term plan, it should include better cylinder heads.

Short term upgrades - 4 barrel manifold and carb, cam in the range of about 214 @ .050, headers and dual exhaust. You can usually pick up about 50 HP, but you may get even more increase because you have such a low performing carburetor.

Longer term plan - Vortec iron or aftermarket aluminum heads. Same 4 barrel manifold and carb, cam in the range up to about 218-220 @ .050, headers and dual exhaust. This package will get you about 100 HP if you don't change anything else. If you are willing to use lower gears and a high stall torque converter, you could use a more aggressive cam and get more horsepower.
Your truck is heavy, so you cannot use an high duration cam (for example, lift at 225-235 @ .050) and expect to have low end power with stock gears and converter.

I like roller cams, and I bought one myself, but it would add a lot to your expense. With a flat tappet cam you could reuse your rockers and pushrods, and just buy new cam and lifters. With a retrofit roller cam you have to buy the cam, lifters, new pushrods, new rockers (usually), and you need a cam button and new timing cover. The upside of using a roller is that it has lower wear, and can handle fast ramps and higher lift cams.

Bruce
 

roundhouse

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350
I would start by Finding an old guy that’s experienced with setting distributor curves and carburetor tuning

Double check the gear ratio so you know what you have
 

Snoots

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Take a pic of the RPO sticker, usually in the glovebox or on a fender under the hood. That'll give loads of info.

Great looking stocker!

On the cheap side, you'll notice a great improvement just by going to dual exhaust with a crossover/balance tube. I'd use 2.5" (63.5mm) pipe.
 

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