Another "Which Cam" Thread

[R-WEST]

Woo-hoo!!  Another cam-choice thread!!    

I'm still dithering on the cam choice for my 390 build.  To reiterate, it's a 0.030 over 390, Probe flat-tops; Ed #60069 heads (10.25/1); port-matched to a Streetmaster with the plenum mod; 750 QuickFuel 'Slayer'; POP adjustable rockers; Duraspark distributor that Faron's re-worked; MSD streetfire box; C-6 with 2500 or 3000 (depending on which cam I end up with) TQ; 3.89/1 gears; 31x12.50-15's; in a 3,500# F100 shortbed (currently in a state of disassembly - http://fepower.net/simplemachinesforum/index.php?topic=2151.0 ); it has power brakes, but I can use a vacuum pump if I need it; for shows/cruising. 

I'm going to use a mechanical cam, and I'd like something with some nastiness at idle, while still being decently streetable.  Neither 1/4 mile performance nor MPG is a concern, but something that sounds nasty is.  I'm 60, and should know better, but..   

I already have a Comp 282S, but am wondering if it's going to be TOO much nastiness.  Mebbe keep it and advance it a couple degrees?

Alternatives I'm kicking around:
Comp 270S    270 270 224 224 .540 .540 110° .022 .022; 1800-5800  (they say "mild rough idle", but how mild is it?)
Howards 252342-10 - 265 265 230 230 .560 .560 110 106 .022 .022; 1800-5800 
Lunati 30330511 .569"/.580" 238/248 272/282 112/106 .022"/.022"; 2000-6400

Reason for the dithering?  I have another custom pickup, an '83 F150 stepside shortbed, with a super-trick 347 that has a pretty nasty Crower hydraulic roller (specs are only 222/226; .540/.555; 108, but it idles like a funny car - so much for thinking we can look at cam numbers and know how it'll act..), and, while it certainly turns heads, it's a bit too much, so I'm thinking I should go a trifle more conservative this time...   

Thanks!!

[fe66comet]

Lobe separation has a huge amount to do with idle. .500 really is not much lift.

[blykins]

The 270S is a great cam for a 390. 

[ToddK]

I have the 270S in a 390 I had in my Galaxie. While the idle was noticeable, it was by no means rough. I even took my 98 year old grandmother for a drive in it, she never complained about it being to noisy or rough. I wouldn't be concerned about using the 282S, I would have used it if the comp in my engine was up where you are planning.

[sumfoo1]

Cubic inch eats up cam.. as does lobe separation angle.

My 511 has more duration @ .050 than your 347 does total and idles a little rough but nothing major ;-)

[SE2839]

I ran the 282S in my Comet for a short time when it had the 390 and again with the 445, the idle quality was not an issue with the 390 and was smoothed a bit with the 445. I'd say keep it. Ed

[bn69stang]

Hey  R West  , we are never to old  lol  and nothing wrong with a cam that makes enough noise to make people take notice .. Bud   

[sumfoo1]

what cams would work in a stock 64 z code 390 (i have a buddy asking)

I advised him i would freshen up the bottom end first but he wants a cam now...

[R-WEST]

Hey  R West  , we are never to old  lol  and nothing wrong with a cam that makes enough noise to make people take notice .. Bud

Darn work's been keeping me from posting..   

After much debate and discussion, we decided to go with this one:
Howards 252342-10 - 265 265 230 230 .560 .560 110 106 .022 .022; 1800-5800.
Should work better with the auto, and have been promised it will still get people's attention.  We'll see..

what cams would work in a stock 64 z code 390 (i have a buddy asking)

So much depends on tranny, gears, etc.., but the old reliable Comp 268H always seems pretty popular...  It sure worked well in my pickup with auto and 3.00/1 gears.

[My427stang]

If you really have 10.25:1 compression, that may be a little too much for that cam

That being said, those pistons will probably be at least .015 in the hole depending on how much you cut the block and the Edelbrocks tend to run big.  If that combo ends up to be closer to 9.8, which it probably will, you should be OK if you degree the cam and watch your timing curve.

If the compression ends up any higher than 9.8, I'd recommend a little more cam, or rock it back to 110 ICL.

This is one of those cases where you really should measure deck clearance, chamber size, and degree, because you are right on the edge

[Ford428CJ]

Huuummm. So many ways to go here. Even the old 427 .525 lift 245 @ .050 on a 114 would sound good. I would have a custom cam made by Oregon Cam Grinders if it was me. Not really a off the shelf kind of guy.... JMHO

[R-WEST]

If you really have 10.25:1 compression, that may be a little too much for that cam

That being said, those pistons will probably be at least .015 in the hole depending on how much you cut the block and the Edelbrocks tend to run big.  If that combo ends up to be closer to 9.8, which it probably will, you should be OK if you degree the cam and watch your timing curve.

If the compression ends up any higher than 9.8, I'd recommend a little more cam, or rock it back to 110 ICL.

This is one of those cases where you really should measure deck clearance, chamber size, and degree, because you are right on the edge

Thanks - I never considered that.  What a great knowledge base this site provides!!    (Jay - you really need a "thumbs-up" emoticon!! ). 
Assuming we do have a 10+/1 compression ratio, how about the 282S advanced a couple degrees instead of the Howards?

[My427stang]

282 on a 104 will run great, but after looking again,  I really doubt you will be over 10:1.  Best to measure everything if you can

[R-WEST]

We're double-checking everything, Ross.
Thanks again for the input!! 

[My427stang]

Glad to help, BTW if you go to the FE Forum, Barry posted a 282S cammed 390, although it's a dual quad, its under 10:1 and has less head than yours. It's still toward the top, see if the rpm range is somewhere around where you want it. 

Probably a good comparison to show that the 282S would be a decent cam.   Depending on what you find for compression, you could still advance it for a little more vacuum at low rpm too