Cam choice for a street strip 440 interceptor

[MagnumForce]

Hi all,
I recently acquired a 1977 440 police interceptor with a cast crank shaft. I am going to be replacing the stock cam and needed some advice. The car is going to have 3.55's with a 727. I plan to make it where i can drive it to the dragstrip an hour away, make a few passes and then drive it home without cruising at like 3500 rpm. I have not purchased anything for the car yet because what ive read is that the cam should be the first thing i get. If someone could point me in the right direction it would be appreciated.
Thanks

[myk]

Well, the 'cam, converter and rear end all have to be coordinated together or you'll get a dog of a car.  It's been a while since I've had to think about that sort of thing, but I believe you decide what RPM range you want your engine to make the most power, pick the appropriate 'cam, pick a supporting converter rated in the cam's power range.  The rear end ratio will also decide how fast your engine reaches its power curve; if you pick something too high the motor will take too long to get into its sweet spot, for example.  Too low and the motor will run out of breath before it should.  The key is to make sure you plan out your parts acquisition properly. 

Hopefully the truly wise street/strip guys will chime in here and steer you in the right direction.  There's also a thread highlighting proven street combo's...

[Cooter]

don't know what kind of numbers you are looking to run with that low compression 440, but camshaft choice will be critical as compression loss will hurt ET.

[MagnumForce]

im shooting for mid to high 11's but if that wont work for my budget then ill be happy with low to mid 12's

[charger_fan_4ever]

For what your looking to do some aluminum heads are in order.

Low compression and that gear ratio in a heavy car you will need to move all the air you can.

[Cooter]

im shooting for mid to high 11's but if that wont work for my budget then ill be happy with low to mid 12's

I'm thinking more like mid 13's to low 14's....

[myk]

Yes, that car will need more than a cam to get into the 11's...

[MagnumForce]

i know that just the cam alone would not be enough and was planning on getting the aluminium heads as well but i was told that the cam is the first thing I should do to the engine 

[firefighter3931]

A cam and aluminum heads won't get you there either....you need more compression to make it all work well together 

My old combo ran a best of 11.68 @ 116.5

-446ci with 535hp/540tq
-4.10 gears with drag radials
-4200 stall dynamic converter

These cars are heavy in street trim and it takes some serious power to make them "track fast" 


Ron

[HPP]

A '77 is a low compression 440. You need to pump up the squeeze ratio before you worry about cams or heads, and then it is a package deal.
Your '77 engine has maybe an 8:1 compression ratio and makes maybe 220-230 horses. If your shooting for 11-12 second e.t.s, then work backwards from there and that will tell you how you need to build.

To get in that range at sea level, you'll need around 450 horses with around a 3:73 gear and a 28" tall tire. So you need to double the output of your engine and get its power down quickly. That is not going to happen with a cam change. This is a tear it down and rebuild it scenario.

If that is not in the cards and this is a bolt on part exercise, then realize you are talking about 14 second e.t.s with maybe 275 horses with heads and a cam change.

[heyoldguy]

Use the 75cc Edelbrock E-Street cylinder head (heck we've already proved you don't need the compression...but it does help, so you could even use the 84cc RPM head), camshaft, intake manifold, headers and carburetor and you can get 450HP/470TQ @ sea level.

See the proven engine combinations and the low compression 440 test to get an idea of what can be accomplished with a stock bottom end.

I DO NOT RECCOMEND the 509 camshaft but it did make some nice horsepower and 441 TQ @ 3000 rpm with 38 degrees total timing in the ignition. I guess I should put the engine back on the dyno and pull it down to 2000 rpm to see what it will do. A lot of people seem to think it won't work down there, really wish I had tested it.

[Cooter]

Without paying A LOT for porting/camshaft/ induction secrets, you will need to up the compression of that engine to make decent power on pump fuel with very low compression.

With those numbers you are 'hoping' for, you will need somewhere between 480-550 HP to run them in a heavy car.


A locamotive engine at 7.8:1 compression will make 800 HP due simply to its size. Same thing with the 440 at 450 hp... That isn't enough to get you where you wanna be.

[BY RSCO]

All the above is good advice. I am shooting for 11.30s and to do that (and to be able to drive it all I want) I went the stroker route, aluminum heads, etc, etc. It is not a cheap project. Will be 10.5:1 when finished, and happy all day long on pump gas. Definitely get the compression up first and foremost, then go from there. You will be better well served also to figure out what the rest of your combo will be within the budget you wish to spend, then pay the small bit extra and have a camshaft ground.

[RIDGERACER383]

If you don't want to spend the money to get low compression you can stay in the high compression range and go for twin turbo.But we are talking about 700 - 900 HP depending on how big of turbos you want.The bottom end of your engine would have to be bullet proof.There are so many combos you can do.

[Dino]

I don't see how you're going to have your cake and eat it.  I can see the car make a great run at the strip or make a great cruiser, but not both.  I could not yank my 3.55's out of my car fast enough.  The rpm's drove me crazy even on 55 mph roads.

[rt green]

if you are going to stick with what you have and want a street car to go to the strip once and awhile try giving mr six pack a call on the camshaft.

[MagnumForce]

Just an update, I figured with the amount of power i am trying to squeeze out of the stock block that i might as well go with a stroker. there is guy near me that builds only mopar engines and was told to go to him by almost everyone i talked to. Its gonna cost more but it will be worth it because i will get something alot better than what me and my dad can do in our garage. Even though i am more of a DYI guy, i realize that somethings are better left to people who do this for a living . I will post pictures when its in the car, which will probably be around march or so. I appreciate all of the responses and advice from you guys! See you in the spring

[firefighter3931]

For your performance goals the stroker is your best choice. 


Ron