When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I'm putting my 72 F100's 360 back together and I want to double check on how I should time the cam.
This is what I'm putting on it/in it:
Edelbrock Performer Intake
Edelbrock Performer 600 CFM 4BBL
Crane 343902 Cam and lifter set
Crane 34790-1 Adjustable roller rockers
New Pushrods
Head milled 0.008"
Bored 0.040" over
Pertronix Ignitor I
Pertronix Coil
Stock exhaust manifolds
I'm planning this to be mainly low-end for towing and general street use. I have seen most people say time the cam straight up, but there are some fans of 4-8 degrees advanced. Advice?
Leave it straight up. They ground it like they did for a reason.
Also, I'd suggest a set of headers. They'll help a lot, even on a street driven towing motor. If this were any other motor, the stock exhaust manifolds might be fine for what you're doing. But there are not words to describe how bad those FE truck exhaust manifolds are.
Edit: I do like that valvetrain setup!
Last edited by rusty70f100; Jun 8, 2006 at 03:03 PM.
Just to make sure, I will see stronger performance by putting this cam in...correct?
Rusty70F100, what header do you recommend?
I decided not to go with headers because so many people said they aren't worth the trouble for the small amount of gain they give. I have heard that if I can get ahold of a couple of old 428 Cobra cast iron headers that they are the shiznit.
You may see a marginal improvement. The 360 is a lower compression motor, and as such wont really handle a big cam. The 343901 is about as big as you'd ever want to go in a 360. I would recommend either that or the Crane 343971 for a 360.
I recommend headers with a 5/16" or thicker flange. I also recommend gaskets with graphite so they seal up good, as well as aluminum collector gaskets.
The 343902 is the 343901 plus the lifters. Or did you know that?
The 901 is greater lift and longer duration with a 2 degree shorter lobe separation than the 971. Forgive me, but I don't know anything about how different cams work when it comes to lift, duration, and lobe separation. Where would I see the difference between and 901 and a 971? I know the 901's operating range is shifted up 500 rpm above the 971, but will that be a noticeable difference in engine output and feel?
Last edited by improvement54; Jun 9, 2006 at 08:50 AM.
Reason: added text
Yes, I did know the 343902 is a 343901 with lifters. Also, the 343904 is the 343901 cam in their "truck" line.
The 971 will have more low end torque. Also look at Crane's recommended compression ratios for these cams:
343901: 8.0 to 9.5
343971: 7.75 to 8.75
The 343971 more closely fits the motor when you look at compression ratio. I think either would work fine for what you're doing though, so it's just something you'll have to decide!
The 343902 came in last night so, my decision is whether to wait another week to put this thing together and go with the 971 or get it running finally. I'm thinking that I'll just keep the 901 and see where it puts me. At this point, the wife was expecting this little project to be on the road, so she's putting some pressure on me too. I hope I'm happy with it. I should be easy to please, because I've never driven it with good head gaskets or a cam without a couple of wiped lobes.
Me too! Unfortunately, I found out today that the roller rockers I'm waiting on won't ship until 7/15. I really want these, but I cannot get them any quicker. It almost makes me want to go with solid rockers instead of rollers.
Ahhh, yes. I didn't see that you had posted. They are indeed the 34790-1's. They are still slated to get here on about the 18th, but if you can get them to me quicker that would help. I'm moving on July 27th and I'd really like to have this baby up and ready to haul by then.
Just use the stock rockers till the rollers come in. Probably safer breaking the cam in with em anyway, instead of chancing a possible mis-adjusted rocker. The rockers are so easy to swap anyhow.
I would but they are completely worn out. It's a wonder that the thing was even running without making any noise. Of course, with it missing on two cylinders because of a blown head gasket and a leaking exhaust manifold, I couldn't really hear much else.