kbog54

i got a good deal on a new crane powermax cam with the following specs:

RPM RANGE: 2000 - 5500

DURATION @ 0.50 : 214/220

LIFT: .452/.465

i was considering one point six to one ratio roller rockers and wondered if there would be any clearance issues with the stock heads and valve covers

also would i need to replace the valve springs with heavier ones or use stock ones?

Damon

Cam should work just fine. Rocker learance up under the valve covers is more a function of how "fat" the aluminum roller rockers are. Stock rockers or aftermarket stamped steel ones with a roller tip will never have a clearance issue with the valve cover. Regardless, I wouldn't run 1.6s on stock heads with that cam. Most stock heads the retainers will hit the guide seals at only about .470" valve lift unless you have the guides machined down. And you're close to that even with 1.5s.

I would definitely replace the springs with the recommended Crane 99848 springs. They are a drop-in replacement for the stockers and will take up to .500" lift without a problem. Stock springs will take similar lift without binding but they don't have nearly the spring pressure required to control a performance cam in the upper RPMs. With access to compressed air and a spark plug fitting you can replace the springs without taking the heads off.

Unless you really want to take the heads off and make this into a bigger project than it needs to be I would simply install the new cam/lifters/springs and put the stock rockers back on for now.

WS Sick

Freind of mine is running the cc305 in a stock 350 TPI and it likes it.

It is 220/230 .050 and 510/510 lift, so that cam youre wanting will have no problems (but do get the prom reburnt with the cam in mind)

AutoRoc

It will work definately.

New Springs are WANTED not just needed. Your car probably makes terrible power because of the old valvepsirngs.

1.5 ratio rocker arms will be fine. 1.6's DO fit under stock covers from what I've seen but you have enough lift if that was your concern. Goodluck man!

aklim

What else are you doing? It robs performance when you go with a stock intake system. Get that done and then the heads before you go with a fancy cam. Who gives a crap if the cam will work with stock TPI. Go aftermarket and get the EPROM reburnt. It is a simple process really. Heads are the first place I would attack but that is me.

RedIrocZ-28

For reference I went with a very similar cam, stock heads, stock intake, new pistons, 2400 torque convertor, headers and full exhaust and dropped 1.2 seconds off my 1/4 and gained 8 mph. Then I went aftermarket intake and AFR 195 heads and custom grind cam and still run 13.7 @ 100mph. I'd rather have my stock heads and intake back. It was a torque monster back then.

kbog54

My plenum is heavily ported and my runners siamesed, so that isnt a problem.
I cant afford to buy new heads or go with an aftermarket intake because i'm in college and dont have much extra money.

So the general consensus is that I shouldn't go with the 1.6 roller rockers? About how much more horsepower are we looking at with that mod?

quickchicken

you can also use a comp 981-16 spring in your app. im running a 480/480 lift 210/220 @50 112 LSA on my 305.
i will say you will most likely need some tuning with that cam. i cant say much about crane products but being i work at comp and run their products im quite pleased. if you are looking to do a swap i sugguest calling comp and ask for Chris Padgett. he is very stright forwardand all around nice guy.
one thing you might want to research is driveability. also is this going in a 305 or 350? and what is the LSA on this cam?

WS Sick

Definately get some new springs and retainers to go with it, the stock retainers limit installed height. The change from 1.5s to 1.6s will leave only about 10 to 15 hp at the very most on the table. If youre worried about them hitting then just go 1.5s the new cam will have enough lift to make a big difference.

kbog54

another question, I also have a production LT4 cam that I can use. the specs for that are :

duration, I 203 / E 210 @ .050 lift

476 Intake Lift, 480 Exhaust with a 1.6 rocker

115 lobe center.

Will this cam make more streetable power?

I know that i have to shorten the cam gear drive pin cause my waterpump isnt cam driven.