Cam Advice

[RustyCrankshaft]

For that combination, I'd like to see 130-140 seat and about 350 open.  That has worked well for me in hydraulic roller FE's in the past with this type of scenario.

One of these days I'll talk to my Comp rep about all of this because I think the "recommended" parts, along with the notes underneath the camshaft description are really misleading.  There are too many variations of FE heads, machine work, modifications, etc, etc., for the parts to work together as they do in their book.  Even something as simple as switching to a tool steel retainer can really screw up the valve spring pressures, as a lot of those retainers have a +.100" install height.....

When I was eyeballing the C1AE heads for the 390 I'm putting together now it looked like my as cast heads would put my installed height about 1.830 once all the spring seats were evened out. Once I got all my new PAC stuff I ended up a few tho over 1.900 even tho they were "std" height retainers. Nothing a little cutting and a spring cup didn't fix, but if I had just thrown them together based on what was recommended I'd have been about 95lbs on the seat instead of right at 140! You really can't use anything in the catalog other than the camshaft specs themselves until you  start checking to see what you have, the original castings are all over the map. I'm amazed more people don't run into serious trouble when they "book" build the heads from recommended parts in the foot notes.

To the OP. It certainly is more costly to go roller, but these days I have a hard time not doing it. On a mild engine it's debatable whether they make more power or noticeably more than a similar flat, but with break in issues, oil quality, etc. it's hard to NOT justify the extra 500-600 bucks for the peace of mind a roller gives. Not that I dislike flat tappets, but if the budget is there I'd go roller every time if I can.  Plus if it's a decent flat tappet you'd probably have to use a "breakin" spring and then put the real springs in after the cam run-in and I'm lazy, too much work for me!

[440sixpack]

I called comp and they were of some help but not a bunch.  they assured me the 924 springs would do for my application below 5000 RPM but I understand what you're saying and will check it out if I go this route.


The say a bronze gear is all they sell for this cam.  I will look  elsewhere for an alternative.

He said vacuum should be sufficient.


This is about the mildest roller I can find or I'd be looking at something else.

 He said the idle should be a little lopey but not radical,   this is of course subjective.  do you think that's an accurate description given the specs on this cam ? 


 

[blykins]

You need a steel gear.  Crane or MSD/Mallory offers them.  Comp doesn't because they simply don't stock them. 

I think Comp Cams makes a spectacular product.  They grind all my custom cams for me.  However, the guys answering the phone surprise me sometimes. 

Vacuum will be more than sufficient for a 270/276 cam. 

[440sixpack]

thanks,  I'll look for that gear.

I guess all that remains is will the idle.  is this thing going to spit and sputter  ?   I don't mind that in my '70 Challenger but I'm going to feel like a dork in a highboy if it does.  a lope is okay but nothing more.  being a 428 bored .30 over should help compared to a 360 or something I assume.

[blykins]

No cam with 53° of overlap will spit and sputter. 

[My427stang]

Here is a 396 FE with a 270H, glasspacks, no X-pipe

https://youtu.be/QOJu-q8YvQM

Here is the same cam in a 445, but with an X pipe in the exhaust and quieter Jones mufflers

https://youtu.be/lgnbTb09UQk

One last one, more cam, this is a 282S but wider lobe sep (58 degrees overlap)  Same 445

https://youtu.be/Uf3D5c9ZZfs

The cam Brent recommended  should be between #2 and #3 I'd estimate with a 428

[WerbyFord]

I have a 428 in my 76 highboy  ( 4x4 F-250 )  the prior owner rebuilt 66,000 miles ago.  it ran perfect but leaked oil awful so I'm going through it.

It has 9.5 -1 compression, headers and a 4 spd.   the cam he chose is a basic 391 truck enging cam.  it's not sporty but runs very well.   


My question is two part, the cam looks and measurs out well, I'm not a cheap skate but as you know cam break in is risky and if this cam is good that takes care of that.  66,000 miles too many to put it back in ?

 The other question is if I were to buy a new cam what would it be ?  this is just a street driven pickup . I wouldn't mind something up to a 262 Comp style cam but nothing more.  better ideas ?  and how much lift can I go without positive valve seals ?  my heads are at the shop now I could have them machined.

What are the head casting & intake casting numbers? What carb are you running?
Trans? Gears?
Guessing the big rig curbs at about 5500 lb?

Depends on use but if its a lot of around town, that cam is a little small but if good I'd leave it in there. Check all the lifter bottoms, are they still convex or at least NOT concave? Check the lobe lift on all 16, how much are they worn? That's what I do before re-using a cam. 66,000 is not a lot of miles IF it was treated right.

[440sixpack]

I measured it out and it has enough wear I decided to toss it.

So my current plan is to replace it with a hydraulic roller.  I wish they made a milder roller cam but for whatever reason they don't for an FE. 

Personally I've never had a flat tappet cam failure , maybe because I load them up on zinc before break in or maybe because I've just been lucky.   but nobody's luck holds out forever so the roller seems like cheap insurance. the older I get the more I hate to " re-do " things.

[My427stang]

I measured it out and it has enough wear I decided to toss it.

So my current plan is to replace it with a hydraulic roller.  I wish they made a milder roller cam but for whatever reason they don't for an FE. 

Personally I've never had a flat tappet cam failure , maybe because I load them up on zinc before break in or maybe because I've just been lucky.   but nobody's luck holds out forever so the roller seems like cheap insurance. the older I get the more I hate to " re-do " things.

Get out of the thought you have to buy from a catalog, custom ordering isn't much more expensive, Comp has lobes as small as 230 advertised and 178 @ .050.  You can get ANYTHING you want

The days of custom cams being unreasonable or only for racers are long gone, CnC machining and just in time production are good for the regular guy.  Add a set of Morel lifters and you'll be happy as a clam

You can even go flat tappet with as much flexibility, my own toys, (489, 445, and now the 461 are all flat tappet)

Search for Comp Cams Lobe Catalog, dig around the High Energy/Magnum tables or the Thumpr tables, pick the lobes, LSA and ICL you like and go for it!

[blykins]

You can have whatever you want, you’re not tied to a shelf cam.

All of us that build can get you whatever your heart desires in the form of a custom cam that won’t cost but a few bucks more than a shelf cam.

[440sixpack]

Crap, I just ordered one.  I guess I could send it back I'm not sure. 

How long does it take to get a custom cam and who would I talk to in order to get one ?   choosing my own specs isn't going to work because all I know is I want less.

[My427stang]

Crap, I just ordered one.  I guess I could send it back I'm not sure. 

How long does it take to get a custom cam and who would I talk to in order to get one ?   choosing my own specs isn't going to work because all I know is I want less.

Look up one post   Brent, BarryR, and Blair won't push their wares on a public forum, but Brent's been helping the whole post and his website is right in his signature.

[440sixpack]

I wondered that but I thought he just built engines.  perfect.

[RustyCrankshaft]

It depends on how busy the cam grinder of choice is, but the hyd roller I ordered from Brent last month took a week to get to me from the time I ordered it. On a Sunday no less, where do you find that kind of customer service these days? Most of the vendors in the FE community are great.

[driveamerican]

I know the next Time I need a cam I will use someone one this site to spec a cam and purchase from them. I have been wrong to many times to guess again. Take advantage of the resources we have as members of this site the increase cost is nothing compaired to the disappointment of a missed guess IMHO.