I'm just not satisfied with the low-end performance of my 390. I left the cam stock-360 pickup cam. Now I'm thinking that was a mistake. The Crane 34052 looks good to me. Intake and exhaust lift is .553 and duration is 272.
Any opinions? I'm just looking for a mild performer for cruising, gas mileage is already out-the-window, 3.00 rear end.
Is valve-to-piston clearance an issue with this cam? I had about .020 deck clearance when I put her together.
Thanks for your opinions, Brett

 

We need more information about your build. One thing hurting you is that 3.00 rear end. If you built a 390 from a 360 and used 360 pistons then your compression ratio should be ok....around 9.5 to 1. If you used the truck 390 pistons then you've a low compression engine and that will hurt you. When you start with the cams and are looking at increasing maximum hp, torque, you end up trading off the low end...the increase in performance comes at higher rpms. When you start the higher rpms, then you've got to be able to get more in...meaning you need a performance intake a carb...sized for your target....and then you've got to get all that out....meaning you need headers and a decent exhaust system. These are sorta the general rules. I would say that the cam you're choosing is a decent cam...but if what you're worried about is your low end performance then I'm not sure the cam is the answer. I'd be more inclined to drop a different gear in the rear....3.5, 3.7, 4.1...something like that.

Good Luck!

Tracy

 

This came up recently and as I recall Krewat put some numbers in there for a good explanation of the increased torqque factor. The rearend was surely the correct way not only to increase the torque but to be able to estimate where you want to be, vs a cam where it's only a small increase at best.

here____ https://www.ford-trucks.com/forums/6...ghlight=torque

 

I had a 3.50 rear-end, and you had to shift (granny-gear four speed) at about 15 mph. Any increased low-end performance was lost in the shifting process.

I built this engine with the flat-top car pistons with the eyebrows-they are 390 pistons, rods, and crank.
It's got a 650 Holley 4bbl, with the S code manifold, Heddman headers, and dual exhaust (turbo mufflers)
Thanks for your help, Brett

 

Sounds like you've got a pretty good setup on the engine. You might as well change the cam and see if like it better. To do it right you need to change the springs on the valves to match....not that big of a deal to do....you can do it with the heads on the truck...otherwise you run the risk of weak springs not keeping up with the cam...I doubt it would cause you trouble but it's possible to seriously damage the engine if the springs aren't strong enough.

Good Luck!

Tracy

 

The stock springs aren't going to handle a .553 lift cam. You'll need new springs for sure.(although it would be ideal with the factory 390GT/428CJ springs) The Crane 272 degree Energizer cam will work with what you've got. Lift with the non adjustable rockers is .516 on this cam. Good idle, smooth powerband with lots of bottomend. I ran this in a 68 Merc 390 with the 10.5 to 1 pistons, only I had a better intake (428PI) and a 750 Holley (vacuum secondary 3310) Ran fine with 12 degrees initial timing and 89 octane gas.

 

I have a similar question. I am trying to put a 428 crank in my 360 to make it a 410. I think I can use 390 Rods right? Next I would like to put a 67 Fairlane
GTA cam in it(3/4 race cam; not sure on lift and duration) Yes/No? Any help would be appreciated

 

Correct, you use the 390 rods. As for the cam question, you're too vague. The Ford GT390 cam was nowhere near what used to be called a 3/4 race cam. Even that cam designation is a vague one as well. And as far as putting it in a Fairlane, that's not an easy job, unless you have a big block Fairlane to start with. Then the head's exhaust bolt pattern gets you into trouble unless you have a set of GT390 heads or 428CJ heads with their dual exhaust bolt pattern. The stock log manifolds on your engine will not fit in a Fairlane.

 

I have found another (cheaper) option; I found a rebuilt stock 390. How much cam lift will stock valves and springs withstand? I would like to be in the neighborhood of .500 lift. the rebuilt heads have new valves(with larger intake valves), new rocker arms, new double roller timing chain and gears, and new guides. I am not sure about the valve springs.

 

I've run up to a .523 lift cam with the stock 390GT/428CJ springs.

 

what about a staight 390 (not a GT)? The engine has a new stock cam in it right now. Would I need to put different cam bearings in it if I put another cam in? The intake manifold is not on so I can easily access all the lifters. And by the way it does have new rocker arm shafts, push rods, and springs.

 

No as long as the cam bearings are new and your very carefull not to nick them taking the other cam out. They will be fine for the other cam.

 

If you are careful and still do think you've nicked the bearings, don't sweat it. I'm sure I've done this a bunch of times and never had a failure from cam bearings.

 

Well small nicks yes as it's pretty hard not to sometimes with the engine in the car/truck. But a big nick or gouge would have me replacing the bearing. If the engine is out it's an easy job.

 

I just added that, because I've heard too many warnings about it. It makes it seem a bigger problem than it is. I'm sure I've nicked a few in removing cams, hell, it's damn near impossible not to in removing one. But I've never had a failure from it. Just be careful in removing the cam and don't sweat the little contacts you'll make in doing so.