Is there such a thing as Cams for Dummies

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.

Bullet Bob

Full Access Member
Joined
Nov 16, 2018
Posts
107
Reaction score
180
Location
Louisiana
First Name
Robert
Truck Year
1980
Truck Model
C20
Engine Size
454
So does anyone have a source for a place that explains how to chose a cam and whatever needs to be changed with it, possibly in crayon? Got a good ways to go before I’m at the stage of doing motor work on my grandfather’s truck. But I am thinking about swapping cams eventually. Always been told that they put a mild cam for pulling in the 50 year old 454 but have no idea of its specs. As much as I would love to put one in there that would sound like Vinnie Paul Abbot banging it out on the double bass. Probably need to go back with something mild but maybe with a little more spice. Figure by the time I get to that point I’ll have done enough research/learning to make a good choice.
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,446
Reaction score
8,683
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
First thing you need to do is decide what the actual 90 percent of the time use the trucks going to have. Just a cruiser,and pulling a trailer. You shouldn't need to change anything except valve springs andmaybe the exhaust,depending. A cruiser,weekend warrior you'll need a manifold,carb,and exhaust,maybe rear gears. And it escalates from this point on. I love Quadrajets but not a friendly to setup hot rod carb for a novice. @Paladin here you go. You'll need a holley
 

fast 99

Full Access Member
Joined
Dec 31, 2021
Posts
2,029
Reaction score
2,932
Location
Spokane, Washington
First Name
Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
Best thing to do is call a cam manufacturer direct. NOT a customer service line for an online company. You will need weight, RPM, motor size, possibly gear ratio, ect.

Reason I say call direct is some online call centers are just reading out of a catalog. They may know less than you do and sometimes make bad choices. Crane or Crower would be one of my first choices but there are many others. Lifter quality has been spotty, buy name brand. Do not be tempted to over cam a heavy vehicle. Power and millage will suffer badly.
 

TotalyHucked

Full Access Member
Joined
Feb 24, 2020
Posts
3,671
Reaction score
11,855
Location
Auburn, Georgia
First Name
Zach
Truck Year
1985
Truck Model
Sierra 1500
Engine Size
5.3
Best thing to do is google "Camshafts explained" and "How to pick a camshaft" and do a lot of reading. There's a bunch of good articles and YouTube videos that explain how a camshaft works and how to pick one to suit your needs.

You will need to know the rough weight of your truck, decide what your intended usage for the truck is, your rear gear ratio and engine size. Also whether the truck is a stick or an auto (can go with a bigger cam in a stick truck without extra parts, a big cam in an Auto truck needs a higher stall torque converter).

For example, when I first built my truck I decided on my rear gear first. I already knew I was LS swapping and would be putting in a 4L60 auto. I've had previous trucks and cars with 3.73 and 4.10 gear ratios and liked where that put me at cruise on the hwy so I picked 3.90. Then I evaluated the engine (5.3) and what I'd be using it for most (roadtripping and daily'ing). I knew I wanted a lumpy cam but also knew I didn't want a huge converter. So I chose Circle D's basic streetable 3000 converter. So then that gave me a rough cam range to shop in, I knew I'd be ~.550-.600 lift but no more and nothing more than high 220s duration. Ended up with the BTR Stage IV V2 truck cam (.553/.553 lift 224/230 duration 109 LSA) and it was a great combo. It was still just a smidge too much cam for the converter, it would try to walk through the converter at stop lights but it wasn't bad. Drove the truck all over the country like that and loved it.

Then I decided to put a T56 6-speed in it. I also was fighting an oil leak so I decided to pull the motor to fix that and you know how it goes "while I'm here", I decided to put a bigger cam in it since I didn't have to worry about a torque converter anymore. So I went with the Texas Speed Bald Eagle N/A cam (.600/.600 lift 227/234 duration 111 LSA). I did lose some low end grunt between the more aggressive cam and the taller first gear in the trans but that was ok because I wanted the sound and more top end because I intend to autocross and track the truck eventually. Because of the increased lift, I also upgraded to double valve springs with higher seat pressure and upgraded my rockers with trunnion bushings for longevity and smoother operation.

I tell you all that as an example. You can just slap a cam in the truck and be on your way if you go with a mild one, but there are alot of other things that are affected. And that list grows as you get more aggressive with the cam. Just keep that in mind.
 

ChuckN

Full Access Member
Joined
Nov 8, 2022
Posts
1,314
Reaction score
3,996
Location
Bellinham, WA
First Name
Chad
Truck Year
1981
Truck Model
C10
Engine Size
350
I think @Ricko1966 isn't feeling well lol. Seriously the Q-jet is a great carb, but they are very complicated, especially when needing to recalibrate one.
I’ll put on my flame suit when I say this is the reason that I’ve stayed with Edelbroken carbs since I bought my truck with one already on it. It’s like a carb for dummies, complete with crayons, and it got better when I went to the AVS2. Yada yada blah blah…”you just don’t know how to work on a Qjet”.

You must be registered for see images attach
 

fast 99

Full Access Member
Joined
Dec 31, 2021
Posts
2,029
Reaction score
2,932
Location
Spokane, Washington
First Name
Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
Not to change the subject but Q jets, Holleys and Carters are all good carbs. They just get there by different designs. Holleys are easier to repair, modify and parts are more available. Stock GM vehicles will usually have better drivability with a Q jet. Carters don't leak, jetting is more difficult. They all have a place.
 

Bullet Bob

Full Access Member
Joined
Nov 16, 2018
Posts
107
Reaction score
180
Location
Louisiana
First Name
Robert
Truck Year
1980
Truck Model
C20
Engine Size
454
Thanks guys, as usual it sounds like I’m probably making things more difficult than they are. As of right now the truck is an 80 c20 with either 4:10 or 4:11 rear end. 4 speed standard transmission, Q jet carburetor that is supposedly opened up to dump more fuel when you give the pedal full throttle, and a possible unknown mild cam. From what I’m picking up so far since this will be a cruising and possibly pulling truck a mild cam will probably be what I end up with. When I get ready contact the manufacturer direct to get the best one suited for what I want.
 

TotalyHucked

Full Access Member
Joined
Feb 24, 2020
Posts
3,671
Reaction score
11,855
Location
Auburn, Georgia
First Name
Zach
Truck Year
1985
Truck Model
Sierra 1500
Engine Size
5.3
Yep, probably an RV or some kind of torquey cam is what you'll want. Def talk to a couple cam places, they can probably get you a little lope without sacrificing your low end
 

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,755
Reaction score
11,402
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
I’ll put on my flame suit when I say this is the reason that I’ve stayed with Edelbroken carbs since I bought my truck with one already on it. It’s like a carb for dummies, complete with crayons, and it got better when I went to the AVS2. Yada yada blah blah…”you just don’t know how to work on a Qjet”.

You must be registered for see images attach
You won't get flamed from me on that comment. I completely agree. I still believe the Q-jet is the best carb for these engine in our trucks, but yea, the Edlebrock is second to none in terms of ease in custom tuning, or even ease of initial setup. For me with my stock 305 I'd love to have the Q-jet, but the PO installed an Edelbrock, and all the bracketry that was for the 700R4 with the Q-jet is gone. All I had to do the edelbrock was change the metering rods to get it where it needed to be. So $10 and 10 minutes of time. And that is why I'm still running the PO installed edelbrock, because it works fine. Now in the 5 years and nearly 80K I've put on the truck I have had to replace the choke coil twice and freeup the fast idle cam a few times. Which isn't bad, but if I compare that to the Q-jet on my 77 Cadillac, which if it's ever been rebuild it was before I bought it which was 15 years ago or so and it didn't look new then.

Sorry to the OP I did not mean to derail the thread.
 

fast 99

Full Access Member
Joined
Dec 31, 2021
Posts
2,029
Reaction score
2,932
Location
Spokane, Washington
First Name
Brian
Truck Year
81,85
Truck Model
K20
Engine Size
350
Thanks guys, as usual it sounds like I’m probably making things more difficult than they are. As of right now the truck is an 80 c20 with either 4:10 or 4:11 rear end. 4 speed standard transmission, Q jet carburetor that is supposedly opened up to dump more fuel when you give the pedal full throttle, and a possible unknown mild cam. From what I’m picking up so far since this will be a cruising and possibly pulling truck a mild cam will probably be what I end up with. When I get ready contact the manufacturer direct to get the best one suited for what I want.
Making the carb richer may or may not be what is required. Engines need both air and fuel in correct mix. Unless lean, additional fuel will not increase HP. After installing new cam, an O2 meter should on the purchase now list.
 

Latest posts

Forum statistics

Threads
44,160
Posts
950,626
Members
36,273
Latest member
dannyphx
Top