upgrading a camshaft
#1
upgrading a camshaft
I have a 79 f150, with a 300 straight6 still running stock 1bbl carb. I plan on upgrading new intake n to a small 4bbl, 500 or 550, any input on what kind of cam would b good for some more torque and power in the mid range. I'm already talking with the people at comp cams but I wanted some input from the guys that drive em everyday.
#4
#5
Senior Member
What ever you get GET THE VALVESPRINGS TOO! You have lots of torque, shoot for the upper of the rpm range, an under cammed engine is more dissaponting than over cammed, because at least if you go too big it will make power on the top end,
JP91, if its scattering at 3000, its broken, you should be able to turn twice that, my 1981 would float the valves at somwhere past 6000, all stock valve train.
Don t cam it any smaller than you would a 302, cylinder for cylinder, its the same as a 400,
So it has the same needs in regards to airflow, and cam timing.
I would avoid comp stuff, bad troubles, buy crane, schnieders cams has a wide range of grinds for the 300, they have been in business for a long time so the must be doing somthing right. http://schneidercams.com/
JP91, if its scattering at 3000, its broken, you should be able to turn twice that, my 1981 would float the valves at somwhere past 6000, all stock valve train.
Don t cam it any smaller than you would a 302, cylinder for cylinder, its the same as a 400,
So it has the same needs in regards to airflow, and cam timing.
I would avoid comp stuff, bad troubles, buy crane, schnieders cams has a wide range of grinds for the 300, they have been in business for a long time so the must be doing somthing right. http://schneidercams.com/
#6
Senior Member
Holy ****! If your getting yours to 6000 I would love to know how. I have a comp cam so idk if that's the problem or not but I want to run more than 2500. I haven't pushed mine farther than that. Cuz mine will scatter.
#7
Senior Member
Are your valves set right, if your rocker arms are too tight you will get valve float due to lifter pump up. It shouldn t pop or break up, if everything is right it should hit an rpm where it can t rev any higher and level out there.
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#8
Senior Member
No they are just stock valve spring. And I adjusted them like a Chevy valve. Zero lash then a 1/4 turn more. I'm gettin a motor built next month. The guy doing it builds race car motors for a living so I'm
Sure he knows what to do. Do you have any knowledge on what to put in it? I said crane to him and he said ya. It's gonna get more hp but mostly torque. Any light on that subject?
Sure he knows what to do. Do you have any knowledge on what to put in it? I said crane to him and he said ya. It's gonna get more hp but mostly torque. Any light on that subject?
#9
Senior Member
Your valve adjustment sounds about right.
The old valve springs might be weak and not closing the valves quick enough at higher rpm,
That would cause it to scatter. I like crane stuff, seems to always work like it should, with a carb you aren t as limited as the efi motor in what you can run, you only haveto make enough vacuum to run power brakes, and don t have to keep a computer happy.
Weren t you running a carter afb on your truck?
The old valve springs might be weak and not closing the valves quick enough at higher rpm,
That would cause it to scatter. I like crane stuff, seems to always work like it should, with a carb you aren t as limited as the efi motor in what you can run, you only haveto make enough vacuum to run power brakes, and don t have to keep a computer happy.
Weren t you running a carter afb on your truck?