Author Topic: Cam Suggestions  (Read 2159 times)

mygt350

  • Full Member
  • ***
  • Posts: 152
  • Second Owner 5S228
    • View Profile
Cam Suggestions
« on: February 12, 2019, 07:42:22 PM »
Am having a 302 stroker (331) built for my sons 65 A-code and am searching for your suggestions as to which cam I should look hard at. Engine is a forged piston 10.5:1 compression, H beam rods, forged crank, AFR 205 heads to be fitted to a C4 3-speed automatic. Rear gears are 3.50:1 posi. Ignition will be MSD with EFI fuel delivery. Most likely Atomic EFI unit.  Want a hydraulic roller cam with lot of lower RPM torque with power thru 5500-6000.
Looking for suggestions as to lift, duration, overlap, LSA. Appreciate your thoughts. One suggestion I have received is a 218/228 .544/.544 112 LSA. Want one that shakes the ground at idle but screams. Remember, its an automatic.
Thanks
Martin
Continuous caretaker of 5S228 since May 1967

shelbydoug

  • SAAC Member
  • Hero Member
  • *
  • Posts: 2100
    • View Profile
Re: Cam Suggestions
« Reply #1 on: February 12, 2019, 08:08:10 PM »
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=31-334-4&Category_Code=SBFMFTCMM

Compcams 282s. You don't need that much head. The AFR 185 # 1388 is plenty. the 205 is if you are going over 600 lift and to 7500rpm. That's impractical for a street Windsor.

Solid lifter. Similar to a souped up hi-po cam. You can go to 1.7 rockers and get around .550 lift.

Looks like you are contradicting yourself with selected components. 3.50 rear won't do much.

You could go auto OD instead of C4 with maybe 4.33 or so gears. Then the 205 heads start to make sense but this isn't a Tournament of Roses Parade car.
« Last Edit: February 12, 2019, 08:21:26 PM by shelbydoug »

mygt350

  • Full Member
  • ***
  • Posts: 152
  • Second Owner 5S228
    • View Profile
Re: Cam Suggestions
« Reply #2 on: February 12, 2019, 08:19:56 PM »
Isn't the 282S a flat tappet cam?
Continuous caretaker of 5S228 since May 1967

shelbydoug

  • SAAC Member
  • Hero Member
  • *
  • Posts: 2100
    • View Profile
Re: Cam Suggestions
« Reply #3 on: February 12, 2019, 08:21:56 PM »
Isn't the 282S a flat tappet cam?

Sure is. Solid lifter.

mygt350

  • Full Member
  • ***
  • Posts: 152
  • Second Owner 5S228
    • View Profile
Re: Cam Suggestions
« Reply #4 on: February 12, 2019, 08:37:58 PM »
Already have the 205's with roller lifter springs. Also have 1:6 roller rockers and hydraulic roller lifters. Probably got horse bit before cart, but that's why I am searching for a hydraulic roller cam. I do have a better 3rd member that may find its way into the car.
Continuous caretaker of 5S228 since May 1967

Jcole65GT

  • Newbie
  • *
  • Posts: 3
    • View Profile
Re: Cam Suggestions
« Reply #5 on: February 12, 2019, 10:55:25 PM »
The Comp 35-514 in my 331 with AFR Renegade 165 heads made 434 HP @ 6000 and 452 lb/ft torque @4200. Smooth idle and good fuel mileage. 3.50 gears in 65 Mustang and stick.

1967 eight barrel

  • Hero Member
  • *****
  • Posts: 829
    • View Profile
Re: Cam Suggestions
« Reply #6 on: February 13, 2019, 12:21:25 AM »
Just out of curiousity, how old is your son?
Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For there you have been, and there you will always long to return.
"If It's Not Boeing, I'm Not Going!"

shelbydoug

  • SAAC Member
  • Hero Member
  • *
  • Posts: 2100
    • View Profile
Re: Cam Suggestions
« Reply #7 on: February 13, 2019, 07:43:39 AM »
Already have the 205's with roller lifter springs. Also have 1:6 roller rockers and hydraulic roller lifters. Probably got horse bit before cart, but that's why I am searching for a hydraulic roller cam. I do have a better 3rd member that may find its way into the car.

It's a great head and it won't hurt you but it does use raised exhaust location. It's raised 1/4". It doesn't sound like much but that engine compartment is very tight for headers. That 1/4" is going to require a good ball peen hammer use on those headers. Don't get the headers pre-coated. Fit them first, then send them out for coating.

The AFR 1388's are the biggest set before they raise the exhausts. From the 195's up, the exhausts are raised.

Mine is a 347. When I looked at flow numbers, corresponding cam profiles and intended use, I went 185's. One of the magazine reviews called them "street/strip heads". Above that, "race heads".

The 1388's flow 297 at .550 lift. That's better then stock  Boss 302 heads.

You will want bigger tubes with the header primaries also. 1-3/4" JBA's or Hooker Super Comps. The Hookers hang down. The JBA's don't. The JBA's are very close to the Pitman arm but fit well other then that. They tuck up high.

On a convertible there is a steel plate bolted across the bottom of the drive shaft tunnel. That is a consideration for header choice. The JBA's will clear. I'm not sure the Hookers will?

Incidentally, that Compcams roller profile,  35-514 is intended for Ford Roller Lifter blocks. Which block are you using?

Here's the problem with cam recommendations. The performance results now are highly predictable. How the owner feels about it is unpredictable. What is mild to one, is radical to someone else.
« Last Edit: February 13, 2019, 08:12:51 AM by shelbydoug »

Brent

  • Jr. Member
  • **
  • Posts: 57
  • 66 GT350 Tribute
    • View Profile
Re: Cam Suggestions
« Reply #8 on: February 13, 2019, 06:54:33 PM »
Why not spend a bit more and have a cam custom ground? Especially since you already have the valvetrain, you can have a cam ground based on the lift limit of your springs and the rest of the specs built for your planned use.
'66 GT350 tribute built over 12-years and finally being driven!

madeulook

  • Full Member
  • ***
  • Posts: 114
    • View Profile
Re: Cam Suggestions
« Reply #9 on: February 13, 2019, 09:20:59 PM »
I have most recently moved to the 4 pattern Comp Cams Nascar camshaft rated for 7200 rpm. It's hydraulic. In addition, I changed to a 351 firing order.

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=CTGY&Store_Code=CC&Category_Code=4PHRSBF

Get the new micro polish option.

I theory the cam duration evens out the air charge to each cylinder. Long runners vs. shorter runners.

Steel distributor gear.

Probably the most important part of the build is the cam.

SFM5R-madeulook
1965 GT 350 Competition Tribute
1st. place pop vote Mid-Ohio

1967 eight barrel

  • Hero Member
  • *****
  • Posts: 829
    • View Profile
Re: Cam Suggestions
« Reply #10 on: April 08, 2019, 01:53:44 AM »
No one has a cam cut around the max compression of the springs, but the cam requirements. The springs are chosen to work with the cam.  You're not going to be turning 7200 rpm on the street and you're going to lose all your bottom end with cam designed for that rpm range.
                                                                     -Keith
Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For there you have been, and there you will always long to return.
"If It's Not Boeing, I'm Not Going!"

Brent

  • Jr. Member
  • **
  • Posts: 57
  • 66 GT350 Tribute
    • View Profile
Re: Cam Suggestions
« Reply #11 on: April 08, 2019, 01:57:38 AM »
No one has a cam cut around the max compression of the springs, but the cam requirements. The springs are chosen to work with the cam.  You're not going to be turning 7200 rpm on the street and you're going to lose all your bottom end with cam designed for that rpm range.
                                                                     -Keith

You can if you already have the springs and don't want to change them, within reason. Not saying this is the best solution but I've done it in the past and it's worked well. Additionally, this is the exact case the OP is in.
'66 GT350 tribute built over 12-years and finally being driven!

1967 eight barrel

  • Hero Member
  • *****
  • Posts: 829
    • View Profile
Re: Cam Suggestions
« Reply #12 on: April 08, 2019, 02:30:24 AM »
Half-ass never ends well.  You can't just pick a cam. I've built enough engines to know. The manufacturer specifies a spring rate and height for a reason. I also had to order custom pushrods on several builds.  So a length checker is also required.  At the end of day the OP is being given misinformation that could wind up destroying the engine. He won't know if he has adequate valve to piston clearances either.
Obviously he's not working on a Shelby. So he might want to try the Vintage Mustang Forum. Most of us won't cut up a Shelby for things like fuel injection.
                                                                               -Keith
Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For there you have been, and there you will always long to return.
"If It's Not Boeing, I'm Not Going!"

Brent

  • Jr. Member
  • **
  • Posts: 57
  • 66 GT350 Tribute
    • View Profile
Re: Cam Suggestions
« Reply #13 on: April 08, 2019, 02:39:21 AM »
I never suggested the OP should randomly choose a cam that doesn't match his springs. I don't consider having a custom ground cam made that is optimized to your usage, but doesn't exceed your springs' specs, as half-assing it. Anytime you assemble an engine you obviously should check pushrod length and PtoV clearance; these are easy to check and the required tools cheap to acquire. 
« Last Edit: April 08, 2019, 02:41:38 AM by Brent »
'66 GT350 tribute built over 12-years and finally being driven!

shelbydoug

  • SAAC Member
  • Hero Member
  • *
  • Posts: 2100
    • View Profile
Re: Cam Suggestions
« Reply #14 on: April 08, 2019, 07:59:14 AM »
You match the springs to the cam. Not the opposite.

I'd expect that on a street driven car with an C4 automatic the cam selection is going to be milder just for the necessity of living with an automatic.

That probably means selecting one that will idle at around 800 rpm and give 15 inches of vacuum.
Right there, that is somewhat of a mismatch with those heads.

It would be a very good idea to run that by a cam grinder and consider a custom cut hydraulic roller. I don't see anything off the shelf that matches the outline.

There are pluses and minuses to those heads. A plus is that you don't need a lot of lift and if you wind up with something around .550 you are about as good as you will get.


Have you thought about using the c-4 overdrive transmission from the mid 70's like in the Granada? That would give you a 4 speed automatic and can help you out with gearing and thus cam selection?
« Last Edit: April 08, 2019, 10:46:55 AM by shelbydoug »