Cams???

[Baxter]

I am getting my list together for what I want in my Engine. It will be a 428CJ probably, {427 aluminum block S.O. possibly}and I was thinking about the right cam for my needs. I will drive mostly on the street at least at first. It seems to me that I would want a cam that "comes on" at higher rpm, what with the light weight of the car and the hookup problem. I would think these cars would run a faster 1/4 with that type of cam. I will have a 5 speed and either 331 or 354 rear. I am more into the stop light game, or 0-100. I don't see myself driving over 100 too often. I just want to get there as quickly as possible. So I want to ask y'all, does my theory on cam choice make sense?, and what cams would you recommend???

[Todd Hedges]

Baxter,
I made a mistake of going with the 3.07:1 rear axel ratio and a Richmond 5 speed.
I wanted the strength but the Richmond only went 1:1 in 5th gear yet with that ratio, the car is quick but you are shifting out of 1 and 2 really quickly.
The engine I had was mild with 450 crank horsepower.
I find that the gearing is too low. 1st and 2nd burn rubber too much.

Anyway the cam that I had at one time worked really well before it got into an all you can eat contest with the distb. gear.
most of the power was above 2500rpm, and once you hit 3,000 look out!

[Candle]

I cant say I know much about the 427,428 or the cam that is right for you. You want to leave the line hard and top out fast without spinning the rear tires. The best key to this is to use a rear end gear ratio near 4:10 to 1 or greater and positive traction. This can also be helped if your drive line can hold the pressure when the clutch is dumped at approx 3000 rpms. With a stock 427 producing 425 hp @ 6000 and 480lbs/ft @ 3700 this can produce rear wheel spin, expecially with 3:50 to 1 or lower rear ends.
If you know your head flow data, compression, stroke, bore, and cam data you could use software like Dyno2000 by MrGasget to come up with approximate data for your specified needs.
Although most frown at using an automatic in a cobra this may be the route to go for jumping off the line. Not for me I would have to say.

[Baxter]

Todd, I read your post about your motor/dist. breaking up , that really blows!!! I look forward to getting together w/ you at some point when your car is back in action. Hopefully you will get some relief from Danbury and the parts manufacturers. So if you could start from scratch, what would you do differently? What gear ratio would you use?? Your setup sounds very similar to what I was thinking, but now you have the knowledge that comes from hind sight. Good Luck w/ the repairs!

[Cobrabill]

Candle-in a Cobra, a hamster on his "wheel" can induce wheel spin.
Where do you get your data that suggests that a 4.10 or higher(numerically)ratio is advantageous?

[Candle]

it all depends on what you are trying to do
with a 3.07:1 you will spin wheels real fast without any effort
on a cobra but by using a 4.1:1 you will bring up the engine revs faster than the rear end revs. Drag racing uses the higher ratios to avoid spinning the rear wheels while lanching hard from the start. granted this makes the car less streetable and highway speeds are less practical and decrease fuel economy. there are trade offs between low rear end ratios and high rear end ratios, but if you noticed the original post wanted to get off the line and top out fast. ie stop-light games. I suggest using an intake manifold that starts producing power at 3000rpm and continues through 8k and your correct on the cam but match it to the heads and intake.

[Hotfingrs]

I think that someone needs to do some real world drag racing and get their facts straight before posting such nonsense...

[Cobrabill]

Candle-you are not going to launch a Cobra hard on the street and have it hook.Ain't gonna happen.If 4.10's were/are such a *****in' idea,then the factory would have done it.Superformance's come with 3.73s and most owners opt for the Tremec 5-speed.These have a 3.27 first in them.Couple that with 3.73s and you have a first gear that's useless and second is so-so.Going higher(numerically) puts you in la-la land.(and i don't mean Hollywood)
If this is going to be a stop light warrior,then the motor has to be built(and everything else)accordingly.Torque wins street races.The gearing needs to allow the motor to work with-in it's power band.You're 3000-8000 rpm figure is a little un-realistic,shall we say?
Getting a FE to make power to 8000 can be done(427TP)but it's going to take $$$$$$$$$$$$ and then some.and then there is the driveability factor-which will be non-existant.

[Cobrabill]

Good Lord-what is with this board?The word b-i-t-c-h-i-n' is a normal everyday word.It has it's origin not to far from where the Cobra was born too.Someone show me where *****is in the dictionary.

[Jack21]

Original question was cam for 428 size motor, warm street use.

First, definately use a retrofit hydraulic roller cam. You won't believe the difference.

Second. Intake duration @ .050 in the 220 - 228 range. Exhaust duration @ .050 in the 224 - 238 range. Typical pattern would be 224/234, .512/.533.

Rumpeta, rumpeta idle, 14 - 16" vacuum (w/roller), good off-the-line, decent street manners 1200 - 2500 RPM, unbelievable torque 2500 - 6200 RPM.

Much less and power goes away at 5500. Much more and street manners go away.

[Baxter]

Jack21,
Thank you for getting to the original Q. Do you think the hydraulic roller is better than solid for my app.? I will be asking for info on individual parts for this engine build. Since I have 1+Years before my car is ready from ERA, I have time to get this right with the help from the knowledge within this club.
I'm thinking Edelbrock alum heads, alum water pump, alum manifold, don't know whose pistons? I hope for 450-500HP, But again, I want quick as opposed to top end. Yet I want to be able to Drive this thing without it being a bear, you know "Balance". What to do, what to do.

All Ideas will be read, the good ones I'm taking notes!

Thanks Guys