What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

New cam

W

Wyatt Tankersley

Registered Member
Joined
Jan 12, 2018
Posts
44
Reaction score
6
So I have a 350 out of a 85 c20, it has a 4 bolt main, edlebrock 650cc carb, dual pain intake manifold, and long tube heads, it is in my 86 k5 blazer with the m465 trany behind it and was wonder what would be the best cam to increase over all power with stock heads.
 
i would love to have a cam that would increase overall power, but it seems, in general, that if you gain in the upper rpm's, you have to give up a little (or a lot) in the lower rpm's and vice-versa.

It might be best to call the cam companies directly.
 
An 85 350 will be a low compression engine unless modifications have been done to it

Presuming it doesn’t need head, valve, or rings
Make sure to replace the timing chain

I’ve used this on several 350s in trucks. Works well
https://www.jegs.com/i/Edelbrock/35...ZwKlLg1BcQxHw76W3d5DPOTSZw2i10rsaAmhxEALw_wcB
Also look to see if you can find a good used aluminum intake. The Edelbrock performer or RPM would be my recommendation
 
I have only used replacement cams that were listed for "Rv/Towing low RPM power"...they still let the engine breathe well enough to let it gain power up to 5000 rpms,which you'll rarely see in street and off road use anyways..

So many get a "3/4 race cam" or a "full race cam" and then are bummed out when the engine runs like crap at idle and around town at low rpms,fouls plugs,and wont pull well until it reaches over 3000 rpms..

I also like lower stall speed torque converters for street and off road,like the ones GM put in diesel pickups and some other heavy duty applications like RV's that have the 6 bolts and something like a 1600 rpm stall speed..
A lot of people put in a converter that "slips" until it reaches well over 2000 rpms and though that may be what a full race cam equipped engine would like,you'll hate it in a street driven vehicle,and chances are good the trans will fry in short order with a high stall speed converter used in street driving..

I've driven a few BBC that had the big port heads and owned a few with the "peanut port" heads and I felt the peanut port heads were better in all around street driving as far as low end power..
The others were very impressive once you wound them up,no comparison..but they bucked and jerked at low speeds and were doggy until you wound them out..
 
Bent77 said:
An 85 350 will be a low compression engine unless modifications have been done to it

Presuming it doesn’t need head, valve, or rings
Make sure to replace the timing chain

I’ve used this on several 350s in trucks. Works well
https://www.jegs.com/i/Edelbrock/35...ZwKlLg1BcQxHw76W3d5DPOTSZw2i10rsaAmhxEALw_wcB
Also look to see if you can find a good used aluminum intake. The Edelbrock performer or RPM would be my recommendation
Click to expand...
I do take it on trails and through the mud and drive it pretty had on the streets would this still be a good cam for that
 
Bent77 said:
An 85 350 will be a low compression engine unless modifications have been done to it

Presuming it doesn’t need head, valve, or rings
Make sure to replace the timing chain

I’ve used this on several 350s in trucks. Works well
https://www.jegs.com/i/Edelbrock/35...ZwKlLg1BcQxHw76W3d5DPOTSZw2i10rsaAmhxEALw_wcB
Also look to see if you can find a good used aluminum intake. The Edelbrock performer or RPM would be my recommendation
Click to expand...
And do you think I would need to replace the springs
 
Wyatt Tankersley said:
I do take it on trails and through the mud and drive it pretty had on the streets would this still be a good cam for that
Click to expand...
I’ve had this cam in 2 different 5500+ trucks used Offroad as well as street driven. Pretty happy with the overall performance
@6872xtc bought my old K5, I’ll let him add his opinion


And I would change the springs, also the valve seals
 
Bent77 said:
I’ve had this cam in 2 different 5500+ trucks used Offroad as well as street driven. Pretty happy with the overall performance
@6872xtc bought my old K5, I’ll let him add his opinion


And I would change the springs, also the valve seals
Click to expand...
Alright thank you
 
also comp cams makes a 4x4 cam line for bottom to mid range power .

my buddy has one in a built 400 sbc around 10.1 comp ratio and loves it so much better than the old more racy street cam he had .

big heavy items need bottom to mid power to get them rollin .
 
Wyatt Tankersley said:
I do take it on trails and through the mud and drive it pretty had on the streets would this still be a good cam for that
Click to expand...

Yes, that is nice all around performing camshaft. I am still using that cam with aluminum heads now and it does a good job moving the fat K5 on one ton axles.
 
Bent77 said:
An 85 350 will be a low compression engine unless modifications have been done to it

Presuming it doesn’t need head, valve, or rings
Make sure to replace the timing chain

I’ve used this on several 350s in trucks. Works well
https://www.jegs.com/i/Edelbrock/35...ZwKlLg1BcQxHw76W3d5DPOTSZw2i10rsaAmhxEALw_wcB
Also look to see if you can find a good used aluminum intake. The Edelbrock performer or RPM would be my recommendation
Click to expand...
Could I leave the stock springs on or would they not work well with the cam
 
Problem with those is that are used. Maybe used up.

Hate to see you squish a valve. Gimme a bit I’ll see if I can track down some springs that work with that cam, but a bit less expensive
 
Bent77 said:
Problem with those is that are used. Maybe used up.

Hate to see you squish a valve. Gimme a bit I’ll see if I can track down some springs that work with that cam, but a bit less expensive
Click to expand...
Does anyone make a kit that comes with the cam, valve spring and timing chain in a similar camshaft design
 
Wyatt Tankersley said:
Does anyone make a kit that comes with the cam, valve spring and timing chain in a similar camshaft design
Click to expand...
I didn't like any of the ones I found. Either more duration, or more lift. Moves the power band up too much, and you don't have the compression to support it
Use these springs
https://www.jegs.com/i/Edelbrock/350/5802/10002/-1

This chain:
https://www.jegs.com/i/Cloyes/220/9-1100/10002/-1

Cam
https://www.jegs.com/i/Edelbrock/350/2102/10002/-1

Again, find a good used Edebrock either performer or RPM intake. I've got them from the swap meet for $40-50
 
I had that 2102 cam in my 383. It had performer heads, intake, and a 600 cfm performer carb, along with doug thorley tri y headers, msd pro billet distributor and it was supposed to be a 9.6:1 CR. It ran great and towed great. I have no idea how just a cam upgrade would act on a stock engine. All of the parts work together and a cam alone isn't going to make the heads and intake flow better or add compression to make more power.

I have always heard that more cubic inches makes a cam act more mild. x2 on wanting great low end torque.

After the 383, I went to a 406 with the same parts but 10.2:1 CR and a comp 270 magnum cam that was 224/224 and had the heads and intake ported. It was a beast but it liked full throttle more than part throttle. Due to the wrong thrust bearings in the crank (from the first builder), it had to be built only a couple years later. Now I'm running a comp 264 hydraulic roller that is 212/218 ( with full roller rockers) and part throttle is very good, but the roller gives a faster ramp rate so it has performance like a bigger cam. My builder would have liked to use a bit bigger cam, but it would not have passed smog here in comnifornia.

It seems that bigger cams always increase the rpm of the powerband and on my builds, especially the last one, they were setup for big torque numbers at low rpm and HP was really not a concern. The current 406 is a rough copy of one from a magazine article (406 Impersonator) where they made 420hp and 525 tq from a 406 sbc. I think they got 400 tq at 2,000 rpm on theirs and mine pulls well at 2000-2500 as well but peaks around 4500 (based on feel when towing).

It does seem like when people go with bigger cams (and dyno with each one) that the HP goes up and the torque can suffer.

As a late teen, I asked my uncle (owns a trans shop and was a drag racer) how to make more power with my 79 C20. He said I had to upgrade all the engine parts to work together to really get a decent difference. Well, a few years later I did it with the 383 and then continued to improve with the next two engines. That journey started 18 years ago.
 
Think of a stock cammed motor as breathing through a straw while having an asthma attack. A bigger cam is like using a larger straw. It' s still having an asthma attack with the low compression, weak heads and choked exhaust.

The cam will help to a degree, not as much as a complete upgrade would.
 
Ran a comp 12-231-2 4x4 cam in a stock 350 with gasket matched 305 HO heads. It was a juicy little motor, pulled like a bastard from idle to 4500 or so.

I ran stock valve springs as well, prob should have put some z28 springs in. That’s about the only thing I’d do differently with that combo.
 
You must log in or register to reply here.

Latest Posts

Top Bottom