SBC Cylinder Head Decision

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

JKRamsey1991

Member
Joined
Sep 22, 2022
Posts
44
Reaction score
83
Location
Kentucky
First Name
Justin
Truck Year
1985
Truck Model
K20
Engine Size
350
Good Morning,

I am planning to rebuild the 350 SBC for my square over the winter. Currently in the parts choosing and planning stage. I am planning on new cylinder heads for the build with end goal of between 350-375HP. Truck is 4x4 will see some use pulling light loads but is mainly a cruiser and hunting vehicle. Currently trying to decide between Brodix IK180s, AFR Enforcer 195s, and Promaxx Maxx heads. Reviews seem to be about equal across the three brands. At this time thinking of a cam with lift between .460-.480, have an Edelbrock intake already as well as a Brawler 650CFM carb. Will also be installing long tube headers at the same time. Figure this would greatly increase HP over the smog era stock 350 it currently has that is pretty anemic.

I know Vortec heads will get mentioned but I already have an intake manifold for old bolt style and with it being carb'd I'd rather not deal with the cold weather issues that some have reported with Vortecs.

So out of those heads what is everyones thoughts? Does some one have any other recommendations? Trying to keep head costs around 11-1300 bucks, but the more money I can save the better.
 

JKRamsey1991

Member
Joined
Sep 22, 2022
Posts
44
Reaction score
83
Location
Kentucky
First Name
Justin
Truck Year
1985
Truck Model
K20
Engine Size
350
They compared the Speedmaster, AFR and the Summit head. The summit is supposedly made by Brodix so I guess it compares two of the three. I'm definitely leaning towards the AFR's but wondering what everyones experiences opinions are.
 

ali_c20

Full Access Member
Joined
Sep 20, 2016
Posts
1,026
Reaction score
1,388
Location
Austria
First Name
Alexander
Truck Year
1974, 1979
Truck Model
C20, K5
Engine Size
350, 350
I have the assembled Brodix IK 180 with a low/mid range torque roller cam and cevrolet performance intake. I can't say anything about performance as I'm in the building process. They look good, are well machined and assembled. Depends what you are aiming for, high rpm or low and mid range power.
 

fast 99

Full Access Member
Joined
Dec 31, 2021
Posts
1,629
Reaction score
2,207
Location
Spokane, Washington
First Name
Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
Mentioned hunting, big cams and carbs don't play well in that application. These vehicles are relatively heavy. Too many times I have seen overbuilt engines in trucks. All they do is suck gas like you own an oil company with no power at low RPM's.
 

Catbox

Full Access Member
Joined
Jul 12, 2018
Posts
3,992
Reaction score
14,572
Location
Just Outside of Portland Oregon
First Name
Peter
Truck Year
1979
Truck Model
C20 Silverado Camper Special
Engine Size
461
I would think that a small intake runner to keep the air/fuel charge moving as fast as possible would be best for a 4x4.

Of those you have listed, the Brodix heads are the smaller options at 180cc.

Pair those with something like a Comp Cams 262 in your preferred lifter style and you should have plenty of power for your 4x4 adventures.
 

JKRamsey1991

Member
Joined
Sep 22, 2022
Posts
44
Reaction score
83
Location
Kentucky
First Name
Justin
Truck Year
1985
Truck Model
K20
Engine Size
350
Mentioned hunting, big cams and carbs don't play well in that application. These vehicles are relatively heavy. Too many times I have seen overbuilt engines in trucks. All they do is suck gas like you own an oil company with no power at low RPM's.

Truck has 4:10 gears in it so I can get by with a bit more cam. From what I have been researching was leaning towards a cam similarly spec'd to the one Catbox mentioned or one of Comps Xtreme 4x4 cams like the 270H seemed like a good match for decent on road stop light performance and driving around the farm.
 

legend57

Supporting Member
Supporting Member
Joined
Jan 11, 2022
Posts
36
Reaction score
83
Location
San Jose, CA
First Name
Rob
Truck Year
1976
Truck Model
K20
Engine Size
400
I ran a Comp 270H on a 400ci SBC in my '57 Chevy for years. Great cam in that car. In my '76 K20 I'm building, it too has a 400, but I'm putting the AFR 195s on it. After talking with quite a few folks, including the engine builder, he thought the displacement warranted the extra volume. The 400 is 15% larger than a 350, so it pulls in that much more air per cycle. To have the equivalent air speed in the intake runner to a 350 with good heads, the 400 should have ~15% larger heads. It's not exactly a 1:1 proportion because the cam comes into play, but the theory holds. A good set of heads on a 350 would likely be the AFR 180s if you're going to keep it below 5-6K RPM.

I chose to go with a roller cam with similar duration to an old "RV" cam, just in a roller flavor. I also have 4:10 gears, only 31" tires and a 700R4 so it should be peppy. I won't be towing or anything extreme. Just a fun driver that can do some work when needed.
 

mrdap

Full Access Member
Joined
Jul 15, 2012
Posts
187
Reaction score
128
Location
USA
First Name
C/K_Lover
Truck Year
81-91
Truck Model
C20/K30/V15/V2500
Engine Size
350/454
As far as cylinder head brand goes, I would go with AFR
 

MrHorsepowerLSx

Full Access Member
Joined
Jun 25, 2021
Posts
277
Reaction score
586
Location
New Jersey
First Name
Jeffrey
Truck Year
1979
Truck Model
K35
Engine Size
454
I have the AFR Enforcers on my K10 SBC build. The truck is doing the same things as your truck, and it runs quite well. I built the motor to run on plain regular octane with low compression and it has no problem making some 11’s on the road with its 35s and 4:56’s the truck also has a 700r4. The AFRs offer the better parts and better bang for the buck. You can see my setup in the under construction page under “k10 Rustoration”. As a side note the AFRs come factory drilled for steam holes if you are running a 400. Im also running a full roller valve train with a cam in the 212/218 duration range

Best of luck with you choices
 

rusted nuts

Full Access Member
Joined
Mar 5, 2023
Posts
809
Reaction score
1,418
Location
Pa.
First Name
Jeffrey
Truck Year
1979
Truck Model
k20
Engine Size
4cly diesel
Truck has 4:10 gears in it so I can get by with a bit more cam. From what I have been researching was leaning towards a cam similarly spec'd to the one Catbox mentioned or one of Comps Xtreme 4x4 cams like the 270H seemed like a good match for decent on road stop light performance and driving around the farm.
Too bad ya can't find a good old school 307 sbc
 

MikeB

Full Access Member
Joined
Apr 4, 2014
Posts
1,749
Reaction score
936
Location
North Texas
First Name
Mike
Truck Year
1969
Truck Model
C10
Engine Size
355
Mentioned hunting, big cams and carbs don't play well in that application. These vehicles are relatively heavy. Too many times I have seen overbuilt engines in trucks. All they do is suck gas like you own an oil company with no power at low RPM's.

I agree. Forget HP, what you need is TQ for the way you use the truck. AFR 195s are the standard, but the Summit heads that Engine Masters tested will work very well. That old skool 270H is a good grind, but a 268H is probably better for your setup. Both are easy on the valve train, too, compared to the Xtreme Energy (XE) grinds.

BTW, that's a good decision to not consider Vortecs. Been there, done that, and they can get expensive fast, with specific manifolds, gaskets, self-centering rocker arms, and more.

Read my signature below.
 
Last edited:

fast 99

Full Access Member
Joined
Dec 31, 2021
Posts
1,629
Reaction score
2,207
Location
Spokane, Washington
First Name
Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
307's were grocery getter engines. They also got a bad reputation with flat cam issues that didn't seem to effect other V8's at the time. There are better engines to start with that are cheap, 350. More CI is always better.
 

mrdap

Full Access Member
Joined
Jul 15, 2012
Posts
187
Reaction score
128
Location
USA
First Name
C/K_Lover
Truck Year
81-91
Truck Model
C20/K30/V15/V2500
Engine Size
350/454
307's were grocery getter engines. They also got a bad reputation with flat cam issues that didn't seem to effect other V8's at the time. There are better engines to start with that are cheap, 350. More CI is always better.
Agree
 

Latest posts

Forum statistics

Threads
42,137
Posts
909,896
Members
33,634
Latest member
prenrag
Top