Recommendations for Cam?

Onewildcat54

New Member
Nov 8, 2022
21
Hello all, earlier I posted a thread about my torque converter possibly being too small. Thank you for those who reached out. I've come to the conclusion my cam is too large for my application. I only plan to daily this car, occasionally hit a wot, and drive on the highway, so its just not applicable. Currently it has a comp cams 12-601-4 cam. I would love some suggestions for a cam, this time Id like to go full roller as well instead of the flat tappet. I've been recommended to size down to a 220/230 cam or something around there. Just to clarify, my 350 is in a 1974 Camaro base with a edlebrock performer intake, 500 cfm carb (which I plan to upgrade to a 650 cfm), 3in Flowmaster pipes with long tube headers, 3.73 posi gears, 1.6 roller rockers, stock heads (whatever came on that year). Furthermore Ive put a high amp alternator, high torque starter, and a summit racing 2200-2800 stall converter. To be honest I want some power behind my wheels, and the car is suited with all the required pieces to run a lopier cam in it, but it still is a daily so Im looking for something not too small and smaller than what's in it currently. Any ideas? What's good out there?
 

Lowend

Administrator. .a car, a man, a maraca.
Staff member
Lifetime Gold Member
Mar 25, 1999
16,895
San Jose, CA, USA
For the record, Cam Specs on the 12-601-4 are
Duration at 050 inch Lift: 235 int./249 exh. Lobe Seperation 107

For a daily driver, with a compression of ~8.5-1 (factory) I'd go no larger than [email protected]
While a narrow lobe seperation will make the idle rattle, it's hurting you on the power side.
I will recommend the Isky 201264/271-12 on this application. (214/[email protected] 112 Lobe Sep)
It's going to feel very mellow compared to the last cam, but it's really the right thing for this combo. If you call Isky, they will grind it on a 108 Lobe Seperation which will give you a little more chunk at idle.
 

73Z L92

Veteran Member
Jan 25, 2011
649
Carlos, MN
As I under stand the smaller LSA (107) will give you more low end power with choppier idle. A bigger LSA (114) will give you more top end power and less chop at idle.
I have been following this from the trouble shooting forum.
I have been wondering how much the stock per the OP 1974 sbc heads will support? I guess what I'm asking is that after the mods the OP is doing will the stock heads just choke off the HP?
 

Onewildcat54

New Member
Nov 8, 2022
21
C
For the record, Cam Specs on the 12-601-4 are
Duration at 050 inch Lift: 235 int./249 exh. Lobe Seperation 107

For a daily driver, with a compression of ~8.5-1 (factory) I'd go no larger than [email protected]
While a narrow lobe seperation will make the idle rattle, it's hurting you on the power side.
I will recommend the Isky 201264/271-12 on this application. (214/[email protected] 112 Lobe Sep)
It's going to feel very mellow compared to the last cam, but it's really the right thing for this combo. If you call Isky, they will grind it on a 108 Lobe Seperation which will give you a little more chunk at idle.
Is that cam roller or flat tappet i can’t tell.
 

Lowend

Administrator. .a car, a man, a maraca.
Staff member
Lifetime Gold Member
Mar 25, 1999
16,895
San Jose, CA, USA
As I under stand the smaller LSA (107) will give you more low end power with choppier idle. A bigger LSA (114) will give you more top end power and less chop at idle.
That is incorrect. We are speaking in broad generalities here, but, all things being equal:

A wider lobe separation angle decreases valve overlap, which will smooth out the idle. This also tends to spread a powerband out. An engine will have a flatter torque curver, over a broader RPM range. This is what you want in a street car and most auto-x applications. Think of a plateau on the dyno sheet.

A more narrow lobe separation increases valve overlap and makes the idle more choppy. This will tend to make higher peak torque and horsepower numbers, but over a much more narrow RPM range. This is great for Circle Track cars that spend their time in a narrow RPM range. Sprint cars for example will wiz from 7000-9000-7000 RPM for an entire race. Having the power maximized in those ranges is key to going fast. Think of more of a knife blade shape on a dyno.

Check out the pic below. As the lobe seperation lines close towards the top, the overlap area (when both valves are open) gets bigger. The more overlap, the more the existing exhaust helps draw in the new intake charge. It also bleeds off cylinder pressure when both valves are open.

cam-pic.jpg
 

Lowend

Administrator. .a car, a man, a maraca.
Staff member
Lifetime Gold Member
Mar 25, 1999
16,895
San Jose, CA, USA
C

Is that cam roller or flat tappet i can’t tell.
That is flat-tappet, which I generally recommend against, but I am assuming you want to stay with the same cam design as you currently have. A Hyd-Roller is better 100% of the time, but that's a whole 'nother ballgame
 

Onewildcat54

New Member
Nov 8, 2022
21
No actually I’m looking to switch to roller away from my flat tappet. I already have roller rockers on there so a roller cam and lifters I’m all for. On that note, is there a roller cam out there with similar specs?
 




Latest posts

Top