347 cam question

OCD4B2 · Post by **OCD4B2** » Thu Nov 04, 2004 10:31 am

I'm gonna be running my 302 up to a 347 stroker, and i was really wondering about the cam. I would probably be adding new heads sometime and will need a new camshaft for it, because i doubt that my old cam can handle 400 horse

. My block is an H.O. roller block so i would definitly need a roller cam. What ones are good for the buck? And just maybe can i keep the old cam?

DBrown · Post by **DBrown** » Thu Nov 04, 2004 10:43 am

what year HO are you going to run?
there are certain years that are already 225HP straight out of the box. I have heard that the factory HO cam is already pretty capable, and if you do a cam swap you will have to junk the E5'S and go to at leat the E7's. there is an issue with the piston to valve clearance. I plan to up grade the top end of the tow rig to HO top end. and the same friend that is walking me threw it is the same one I got that info from.

FatMan · Post by **FatMan** » Thu Nov 04, 2004 1:23 pm

i dont know much about cam's but you could call crane and talk to there tech people. that's what i did when i was looking to rebuild my 351c with roller stuff. the guy hooked my up with what i could do and how much lift duration i should be looking for in the output i wanted. are you buy'n a strocker kitor are you piecing it together?

OCD4B2 · Post by **OCD4B2** » Thu Nov 04, 2004 1:31 pm

My block is a 1990, same year as my b2. What will i have to do to the valvetrain when i stroke it. The pistons are gonna be going down farther anbd i think i might have to set it up for a bigger lift. whats ur opinions?

FatMan · Post by **FatMan** » Thu Nov 04, 2004 6:45 pm

well i know your stocker crank aint gonna work. "i think the 302 strockers use a 351 windsor crank". you'll need new rod's. im not sure of what else you'll need.
you should go with a strocker kit. that way you would'nt have to worry about any thing but the machine work of the block/heads.

DBrown · Post by **DBrown** » Thu Nov 04, 2004 7:30 pm

you will need rods and crank. the kit should have what you need. when you order the kit ask the people what you need to run. I would stay away from a lumpy idle, if you are crawling at idle you will not like it.

OCD4B2 · Post by **OCD4B2** » Sat Nov 06, 2004 1:02 am

Will I have to change any of my valvetrain for the stroker kit? I'm definitly gonna be running roller rockers no matter what and i was wondering if my stock valvetrain will have to be changed.

plowboy · Post by **plowboy** » Sat Nov 06, 2004 7:40 am

Depends on how much lift your cam has. Too much lift creats too much spring pressure. Stock springs and retainers won't hold up especially at higher RPM's(mud boggin). I know Comp Cams has some info on their website. If you know the specs of the cam, they can tell you whether you will need different springs and retainers. My buddies 69 Camaro 427 has .600" lift. (tripple springs)

One thing that I would seriously consider if you are building a stroker motor is to have it balanced. Not much more money to have it done.

plowboy · Post by **plowboy** » Sat Nov 06, 2004 7:40 am

Depends on how much lift your cam has. Too much lift creats too much spring pressure. Stock springs and retainers won't hold up especially at higher RPM's(mud boggin). I know Comp Cams has some info on their website. If you know the specs of the cam, they can tell you whether you will need different springs and retainers. My buddies 69 Camaro 427 has .600" lift. (tripple springs)

One thing that I would seriously consider if you are building a stroker motor is to have it balanced. Not much more money to have it done.

OCD4B2 · Post by **OCD4B2** » Sat Nov 06, 2004 12:05 pm

well what about the roller lifters and the pushrods, I wanna try to run the stock camshaft. and what about the harmonic dampener, will that be changed?

FatMan · Post by **FatMan** » Sat Nov 06, 2004 4:54 pm

if you run a strocker motor you better be ready to put money else where. your inners are going to need to be upgraded or stuff aint gonna last long. you should be able to run the roller stuff but you stock cam wont work with roller lifters. dampener should probably be changed especially if it's got visible damage. you gonna go full roller or just rockers?

DBrown · Post by **DBrown** » Sun Nov 07, 2004 5:24 am

if it is an HO it is already roller cam/lifters.
you can try to run the stock stuff but I can not say if will run all as good as you are looking for. besides you are going to throw alot of money at the bottom end so why skimp on the cam? like I said talk to the place you get the kit from they will tell you what lift and duration you will want to look for in a cam for your application. springs are not to expencive and the cams ar not that high either. if I were you I would go all the way or not go at all. my advice would be to leave the bottom end alone and get a nice set of heads and nice cam. 90% of your HP comes from the top end alone.

plowboy · Post by **plowboy** » Sun Nov 07, 2004 9:10 am

You can get cam sets which include timing chain, cam, lifters, springs, etc. The complete sets are 200-300 bucks. Look up compcams.com or cranecams.com. I know comp cams has a lot of information on choosing camshafts and information on matching componets.

The comp cams set that I am going to get for my 2.8 has new spring, retainers, etc. It cost 300.00 for everything.

OCD4B2 · Post by **OCD4B2** » Sun Nov 07, 2004 5:24 pm

im gonna be running roller lifters and roller rockers. And what about the 331? I talked to more people and they said just stroke it to a 331, it will wind up faster than a 347, but it will still be stroked.

well whats ur input?

plowboy · Post by **plowboy** » Mon Nov 08, 2004 7:35 am

Well I guess if your gonna drag race it you might want it to rev faster. Personally, as much as I like stroker motors, I think you would do well with some head work, midrange cam, intake and balance the engine. With the roller cam/lifters and balance it should rev good and be smooth. For off roading you need torque at lower rmps. Choose a cam that will give you more torque and HP over a broader range, say 2500-5500 rpm.