street car: cams for given engine displacement? what do you think?

[cazsper]

I have been given done really good info on here since I've been a member and I appreciate it. My question my sound a little odd but please bear with me. I am going crazy trying to decide on a small block (Windsor or Cleveland maybe a stroker) or a 460 based motor. My intended use for my '73 Mach-1 is a daily driver.

Do I need a stroker? Nope.. do I need a 460? Nope.. I just might want one. I have a 393w in my '68 coupe and I love it.

Anyway, what I can tell you is that I have (and plan to use) 3.50:1 gears, 275/40-17's in the rear. I will be using a manual trans. Probably a TKO-600. If I go with a windsor, I'm planning to go with a set of AFR -205 or AFR-220 heads. If I go with a Cleveland based motor, I plan to go with a set of CHI aluminum heads 3v or 4v. If I go with a 460 based motor, I'm thinking of going with aluminum cobra jet heads, maybe the P-51 heads. With all of these builds, I'm planning on using the Edelbrock Air Gap intake manifold and a Holley or Demon carb with vac secondaries. (( none of this is set in stone. Just my plan for now)). Living in California with 91 octane, I'm also planning for 10:1 compression.

I will be using shorty headers, appropriate sized (full length) exhaust and magnaflow mufflers.

** from talking to people and reading forums, I have been taking notes when it comes to cam shafts for certain displacement of engines. Given my proposed parts and intended use, what is your impression of the list of (displacement....cam @ .050") I have come up with? Keep in mind, the lift will be moderate to ensure longevity and the LSA will probably be 112' for increased vacuum for power accessories.

351.....224/232

393.....228/236

427.....232/238

460.....234/240

500.....238/244

520.....240/246

Thanks everyone...

 

[wwhite72]

Your choice of heads will be the main determining factor of which cam would work best. The flow characteristice of the head dictates the best valve operation. Check the CHI site for tables showing performance with different cam specs.

 

[Don C]

I agree, the head choice will have more to do with the cam selection than the cubic inches.

 

[woodsnake]

And rear gear! A 3.50 gear isn't much, comparatively speaking. More cam, better heads, and more gear equals a higher rpm power band...

my 289 in my 68 Cougar, has a performer RPM cam,( http://www.summitracing.com/parts/edl-7122/overview/make/ford )

and heads to match, with a T5 manual trans and 3.50 gear. Not enough-car lugs at 70 MPH. I think it might a happier car, with a 3 speed, at this rate. My 69 Cougar, has a comp cams extreme ( http://www.summitracing.com/parts/cca-cl35-246-3/overview/make/ford )

and with a 3.89 rear gear, NEEDS an overdrive..

The 3.5 gear is OK, and would probably be a lot more fun with a more stock engine. With a well planned H/C/I combo, you will need gears to match the power band, and an overdrive trans to take the car on the freeway...

 

[Jeff73Mach1]

Bigger cubic inch versions of the same motor will like bigger cams, but gear selection, car weight, headers, heads, compression ratios valve trains all become part of the selection process.

Also, the type of cam will matter. roller cams have fatter profiles under the curve and solids and solid rollers have better High RPM capability.

There are no set answers- some folks like cams that give good vacuum and others like ones that have the right "sound" Some folks drive like their asses are on fire and others cruise

 

[cazsper]

I should have mentioned, I'm planning to run a hydraulic roller cam. As for gears.. I understand that a little more hear would be fun, I'm thinking 3.50's because I drive on the freeway as much as I drive around town.. as well as the occasional 4 hour trip to Lake Tahoe.

 

[Don C]

You might want to check out this thread:

http://www.7173mustangs.com/thread-camshaft-primer

And Crane has these suggestions and what needs to be considered:

http://www.cranecams.com/pdf-tech-tips/cam-selection13-17.pdf

Comp has this online program that gives you their grinds and recommended axles ratios, transmissions, etc.:

http://www.camquest.com/