flat tappet cam

[fryedaddy]

i have a 428 in my 66 comet that i have owned over 40 years.i have a pretty fresh engine in it with less than five thousand miles on it.i have a comp cam hyd flat tappet cam in it that i bought in the 90s 560-292-.245 at .050.runs good but these days should i switch to a roller cam or just run what i have and forget it. im into performance,but i want my stuff to be up to snuff too. ADVICE NEEDED. I already have HS rockers on it.

[manofmerc]

I dont post much on here but I have flat tappet cams in my comet drag car and my 66 cyclone .The 66 has a 63 427 center oiler engine .It is typical in that it has only splash oiling to the cam and lifters I have no issues with it I built that engine in 2007 I would just leave the cam alone in your comet on the street it would not matter.If you raced it the correct roller might be quicker though .Lots of expense and work to go roller .My drag car has gone 6.61 at 102 with a solid flat cam might be quicker with a roller but it is just fine to me .It has a 460 style engine not an FE.Doug

[blykins]

Going to a roller cam doesn't always mean that you're going to get more horsepower.  It's also a big upgrade, as you're going to be changing the cam, lifters, distributor gear, valve springs, and pushrods.  It will be some $$$ after it's all said and done.  Yours is well broken in and as long as you run good oil, it will last.

If you're wanting more horsepower, you may want to look at another flat tappet.   

[428kidd]

Leave it , if its broken in and doing good enjoy it!

[fryedaddy]

thanks-its a good cam and it works well on the street.one more thing,what is the BAR NONE best oil i can run in it on the street-strip?

[blykins]

There are several that you probably couldn't tell a difference between.

For flat tappet stuff, I run Penn Grade.

[My427stang]

Both of my toys are flat tappet, one because it isn't drilled for oil the other because I had a nice broken in cam very close to what the truck needed.  They work great, I'd say keep what you have

I am also a Penngrade fan, but will use VR1 happily as well.

[fryedaddy]

im confused when it comes to oil weights.i live in east tn-warm temps. what weight oil should i use for hard street driving-wot often

[blykins]

As a rough rule of thumb, in hotter temperatures, you want a more viscous oil.   It will depend on your bearing clearances and a few other variables though.   

[Rory428]

I am also a fan of Brad Penn/Penngrade 1 oil, I have built 5 flat tappet Ford engines for myself, in recent years, 4 of them FEs, for street strip, 9 second drag car, and daily drivers, never had any issues with flat tappet cams when using the Brad Penn/Penngrade 1 oil.(Of course proper assembly, break in, and such also play a large part.)

[My427stang]

im confused when it comes to oil weights.i live in east tn-warm temps. what weight oil should i use for hard street driving-wot often

As Brent said, hard to know now, unless you have notes on clearances.  However, I'd start with 10w40, if you have abundant idle and low rpm oil pressure, you could stay there or go 10w30 next time.  If it's low at idle, and scares you, (10 psi or less) you can go 20w50 or a mix, BUT, remember that thick oil drains back slower too, so it will raise idle oil pressure a little, but also costs you in drainback

I'd bet PennGrade or VR1 10w40 works great though