Need a bit more oomph...

Rusty Nail said:

Meh.
I dont like complicating things unnecessarily.

I vote for 1.5" primary full-length headers and some cool mufflers with an "H"pipe.

I'd blow off everything else and focus your time, attention, and money towards that one. single. modification.
Quite frankly you will not beat that overall improvement to your truck for the money - ever.
Do it up!

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He does make a fair point.
This should be first.
If it cannot breathe well on either end, it will not perform to your expectations.

My big block came with wimpy little 2-1/8 dual pipe system on it and it could barely breathe.
You could hear the fan more than the tailpipes when jumping on it.

Now it has headers with 2-1/2 pipes and mufflers and it is much happier and has rewarded us with way more fun when the pedal is pushed down.

7900_Blazer said:

Much appreciated on a cam direction… You mention that the heads are the biggest problem, thoughts on a direction for heads that won’t break my marriage?

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I would look for a head rated in the 170-185 cc port range. You would want them with a 62-66cc combustion chamber. Looking on Summits website I found several that are affordable. You have the GM Vortech's. They have really gone up in price. There are Pro Max which are aluminum. The reviews on them are hit or miss on the quality. I would go with the Edelbrock E street. https://www.summitracing.com/parts/edl-5089/make/chevro. Edelbrock also has their version of the Vortech, called the E-Tech. You would have to buy a knew intake to run any of the Vortech type. These heads are around $ 1000 to 1200 a pair.

The heads you have on the crate engine have a large combustion chamber that gives you a low compression ratio. The port design is not very good. If you look at the dyno graphs for these crate motors, they make decent off idle torque it's that the small cam runs out of steam at about 3800 rpm. If you replaced the cam with a slightly larger one. Say with about .450 lift and low 200 duration you will pick up power across the whole power curve. The engine should make power to 5000 rpm. If you do the other mods such as headers and performance tune your timing and carb it should be a respectable performing truck.

The choice of a flat tappet cam or a Hyd. roller is really the price. Performance wise the HYD. rollers beat the flat tappers in every way. They have more aggressive ramp rates that make more power with less duration, and they cut down on friction. You don't have to worry about breaking them in or adding an oil supplement. Reto fitting one to a non-roller block is expensive. The lifters are very expensive. You need better springs and a new timing cover to run one. NOTE the head listed above is not for a HYD. roller. Good luck with your build.
On a side note, if you like junk yards you might find a set of TPI heads off of an 80's model Camaro, Firebird or a Vette. They made decent power. I bet they cost as much as a new head today.

I am using a CompCam 12-230-2 / XE250H-10 in my low compression GM crate engine. Smooth idle, good manifold vacuum and low end torque. Edelbrock 600CFM carb on Performer EPS intake and Hooker 2.5 cast iron exhaust manifolds. The super mild 350 moves my 86 K1500 around with ease. Just offering a somewhat similar engine comparison.

.

What's fhe question ...more umph?
Now you M F.ers are talking about FLAT TAPPET CAMS but nobody said "git the nitro!"

Rusty says: "hold my beer here comes the N2O!"
These threads are helpful reading peoples part choices and the factual experiences they encountered.
Vortec heads have become expensive and must be closely screened for cracks but can provide exactly the power and torque our trucks need.

Geoduck said:

Rusty says: "hold my beer here comes the N2O!"
These threads are helpful reading peoples part choices and the factual experiences they encountered.
Vortec heads have become expensive and must be closely screened for cracks but can provide exactly the power and torque our trucks need.

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And they don't work well with carbs or TBI when it's cold out,and they require a special intake manifold, and their benefits over TBI heads aren't there until 4000 rpm and up so. By the time you weigh pros and cons, be happy making good power below 4500 rpm or buy after market heads.

Is this the right time when i'm supposed to plug the best flowing (*cast iron) SBC head ever?
So all of that trendy headache BS can be avoided OR have they actually invented a rounder wheel?

LOL

No.
They didn't.

Let's face it. In reality-land, you can. make that 'hp gain" by running 305 heads and 91 octane.

OR source a pair of #803s.

BUT! I stand on 1.5" full-length headers and an H pipe.
That's (advanced) hot-rodding 101!

Ricko1966 said:

And they don't work well with carbs or TBI when it's cold out,and they require a special intake manifold, and their benefits over TBI heads aren't there until 4000 rpm and up so. By the time you weigh pros and cons, be happy making good power below 4500 rpm or buy after market heads.

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I'm on the TX gulf coast, the Vortech's work fine down here. I went with a GM HYD roller cam . The HT 383 ,Ram Jet engine cam. I'm really happy with this combo. Agree with making power below 5000 rpm. I'm not drag racing my K-10.

Juniors 307 with Vortec heads seems to be just fine.
He bought the chineseium intake from Ebay for $150 and bolted it on.
It had a small casting flaw that leaks coolant, so he used the warranty and agreed to simply pay the $15 shipping for a new one to be sent out to him.
A pea size blob of JB weld over the flaw has stopped the leak and he still has the new one if that lets go.

It may be a bit grumpy when cold, but it just needs a minute and then drives away just fine.
I have seen him wing the tach to 6800 while passing on the freeway and it does quite well.

Just our experience here in Oregon with the Vortec heads and a carb.

Catbox said:

Juniors 307 with Vortec heads seems to be just fine.
He bought the chineseium intake from Ebay for $150 and bolted it on.
It had a small casting flaw that leaks coolant, so he used the warranty and agreed to simply pay the $15 shipping for a new one to be sent out to him.
A pea size blob of JB weld over the flaw has stopped the leak and he still has the new one if that lets go.

It may be a bit grumpy when cold, but it just needs a minute and then drives away just fine.
I have seen him wing the tach to 6800 while passing on the freeway and it does quite well.

Just our experience here in Oregon with the Vortec heads and a carb.

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I've drove mine last winter, with no problems. In SE Texas we don't get many days below 40. I could see if you were in freezing temps for months that it would be a problem. What if you ran a heat riser to the air cleaner?

I don't think that will be done to any of ours, but it could help in a colder climate.

My old Nova didn't have a choke and neither did the VW beetle that I drove in all the weather from below freezing to above 100.
Just hafta let them idle for a bit more before we drive away.

1lejohn said:

I've drove mine last winter, with no problems. In SE Texas we don't get many days below 40. I could see if you were in freezing temps for months that it would be a problem. What if you ran a heat riser to the air cleaner?

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Mine doesn't like cold weather and it has all of the 1981 factory goodies to heat the snorkel. Without the crossover in the heads, it is cold-blooded, but once warm it's fine. Just can't go do a jackrabbit start into traffic until it's gootenwarm.

Ricko1966 said:

Biggest bang,for cheap bucks is going to be gears,cam,and headers/better exhaust. You already have a 4 barrel manifold a different one might make a little difference,but not much, camshaft you need to make a realistic decision as to how you are going to use the truck. Putting in a cam that makes more top end horsepower,usually results in a loss of low end power. Example you put in a cam that makes great horsepower from 2500 to 6000 rpm but you are geared so most of your driving is under 2500 rpm,you aren't going to be happy. Tell us what you are going to use the truck for. A toy? 4 wheeling?Pulling trailers? Just used as a passenger car?

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7900_Blazer said:

I have a 1985 K20. It appears the previous owner put in a crate 350 - likely the lowest horsepower/torque engine - it doesn't have a ton of guts. A few months ago I swap out the SM 465 for an NV4500. It has an edelbrock cab (unknown which carb).

I'm about to swap out the front clip (rusty fenders - easier to replace than fix); and having easy access to the motor, I thought I'd add something - anything to give the engine a bit more power/torque.

I've considered adding a cam but am unsure which cam to swap in. I don't really have the $'s for heads... unless I can find something 'better' but inexpensive. I've also considered adding a better intake... but unsure.

If you are so inclined, could you provide specifics - exactly which cam you ordered or which intake you've had good experience with etc...?????

Much appreciated.

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First, determine what your gear ratio is. If it is overgeared, putting a more aggressive cam in it will only make it worse. What size tires and rims are you running? Larger diameter gives the effect of taller gearing. Lastly, how do you want it to perform? If you value off-the-line snap and the ability to quickly get into high gear, and don't like to have to constantly down-shift, you need low gearing, (high number). If you consider good high-speed manners more important, you need tall gearing. If you are greedy and want both, you need Overdrive. What kind of fuel is available in your area? Hot cams work better with very high compression, but very high compression requires high octane gas. After you have all that figured out, then you can decide if you need a different cam, and what kind of cam.

J. B.