351w cam swap question

[fordman4x492]

hey guys. i have been askin around but havent had any luck. so i decided to check here. when you put a biger cam do you have to get shorter pushrods??

thanks in advance

 

[Beef52751]

you'll have to install the cam and reset your rocker geometry and see. no one will be able to give you a positive yes or no. to many variables

 

[fordman4x492]

so i have to reset the rockers and see if they sit in the center of the valve? and if not then i gota get shorter pushrods?

 

[Beef52751]

pretty much, but intead of just sitting in the center of the valve, mark the top with a sharpie and spin the motor over by hand, try to center that mark as much as possible on the valve

 

[fordman4x492]

ok ima try that bit its gonna have to wait till i get some new lifters because my jack a$$ brother stole mine to put in his 302

 

[Mac]

I take it you have the postitive stop-rocker arms having the 351. There is a pretty good write-up on how to adjust the rockers in one of the books I have. Little bit more involved than the fully adjustable rockers. I'll see if I can't did it up for you.
Dave

 

[adsm08]

Big big cams usually require a special set of lifters anyway. I know the cam in my engine has custom lifters to go with it. If you don't use them, things break.

 

[fordman4x492]

this is the cam i have

http://www.summitracing.com/parts/CRN-444551/

 

[--weezl--]

the cam and rockers should be designed to work with eachother, ie. a conventional cam, and roller rockers, don't work together... as for the length of your pushrods, like everyone said, it depends on the lifters, and cam, but if the cam's closed position is the same as the last cam's closed size, and the lifters are the same, then your pushrods should be the same also

 

[v-8power]

this is the cam i have

http://www.summitracing.com/parts/CRN-444551/

The specs on that cam say operating range of 3k to 6k.
That doesn't sound right for what it is, I would think it would start around 2200. It should sound pretty good at idle though.

 

[Mac]

the cam and rockers should be designed to work with each other, ie. a conventional cam, and roller rockers, don't work together.

You lost me on this comment - why wont they. You can put roller rockers on a '66' 289 with the flat tappet cam. I must say that cam is a bit wild for my tastes but not my build.
Dave of the Nord

 

[fordman4x492]

You lost me on this comment - why wont they. You can put roller rockers on a '66' 289 with the flat tappet cam. I must say that cam is a bit wild for my tastes but not my build.
Dave of the Nord

well the 351w is going in my mustang. i picked that cam because i want it to be a street/strip car

 

[Mac]

well the 351w is going in my mustang. i picked that cam because i want it to be a street/strip car

What heads and rest of the build? Inquiring minds.
Dave

 

[shane96ranger]

What heads and rest of the build? Inquiring minds.
Dave

X2. I'm curious as well, especially the heads.

 

[fordman4x492]

right now it is stroked and bored to a 410 (.040 over, 4 inch stroke) the heads are stock and it has a edelbrock performer intake. but im gonna change the heads and intake.

heads
http://www.summitracing.com/parts/AFR-1456/

intake
http://www.summitracing.com/parts/EDL-2981/

pistons
http://www.summitracing.com/parts/PBP-10466-040/

headers
http://www.summitracing.com/parts/BBK-1511/

transmission
http://www.summitracing.com/parts/CMG-TCET5008/

that is what i want to put in the car but its gonna take a while thow. its gonna be my project for nadc