Hey, I am definetly a newb when it comes to mustangs. How do heads help the performance on mustangs or any car in that matter?

 

The induction system(manifold, carb/efi setup) is the path for air/fuel into the engine, exhaust let's it out, and it all goes through the cylinder head. Heads are most likely the SINGLE(though comprised of numerous parts themselves) most important part of an engine when it comes to efficiency/power etc(though everything else must be taken into account as well). Port design/size/shape, valve placement/size, combustion chamber size/shape, exhaust port/shape/size all determine how the engine is going to be able to breathe, at what rpm range, to what degree of efficiency etc etc. Put simply, heads can make or break and engine. Different heads are for different uses, some are for street, some for mild racing, and some for high rpm fire breathing behemoths. A good head(s) with the right parts in the rest of the combo will make for a very well running engine, crappy heads, no matter what else you have, will tend to make an inefficent engine. Wrong or crappy heads can lead to no power, poor mileage, bad throttle response or something that just plain drives like crap or falls on it's face. It all comes down to efficiency in the rpm range you need the engine to operate, and heads play a HUGE role in that efficiency. Best advice, is get a good book on engine performance and learn the principles of how engines operate.

 

^well appreciated.

 

And also, what heads to reccomend for a 351w

 

Budget has something to do with it also.
Do you want a torque monster that will break the tires loose as soon as you blip the throttle, or do you want a high revving high horsepower motor that likes to run up to 7 or 8K?

You might want to make up a wish list (and post it) of what you want your car to be able to do, like auto-cross, or run an 11 second quarter mile, be a good daily driver, show, plain Jane, stupid fast, supercharged, etc...
Also list what drivetrain your car currently has, and what if anything you are planning to replace. You don't want to build up an engine that is just going to decimate the rest of your drive train. Seems like once you break the 300hp mark you have to spend some money, and as soon as you break the 450-500 hp mark you need to spend a small fortune to build something reliable.

 

Ok, well i have a 351w with 350 hp, gt40 heads which came with the 351, magnaflow exhaust 2.5', Elderblock RPM Manifold/Intake. My budget is around 5k

Wish List: 1)run low 11's on 1/4
2)500-600 horsepower
3) want it to be super fast
4)used for street/no drag

Thanks

 

No drag but u wanna record a 1/4 time.Isnt that a drag???You gonna want everything forged and balanced perfectly for that kinda power.Also keep in mind the 5 grand needs to include a built tranny and rear end or your gonna blow them out with all money spent on motor and then the car sits.That said big cam,flat tops,nicely matched carb.and on and on

 

First, sell your firstborn to pay for the parts you are going to need. The rear end and tranny you will need will easily burn your $5000 budget.

 

^ok i see. Well say if i increased my budget up to 10k, what tranny do you reccomend and where can i get the rear end which can support that kind of power?

 

Naturally aspirated and reliable out of a 351 to get that kind of power is really way too much for the street. Like Bentworker said, a lot of it is budget. To get 500-600hp n/a(or even superchargered) in something you can drive reliably every day is going to take a lot of money. You're gonna need chassis reenforcement, driveline, diff, trans, then the engine itself. Low 11's is FAST for a non drag street car. To have that driveable is going to require forced induction, all forged internals, and a lot of cash. You could easily spend all 10k on the engine aloneto get that kind of power reliably on the street(and may not even reach that horsepower level). You'll also have to do your suspension as well, that kind of power needs serious chassis/suspension to be able to control. If you run stock leaf springs with that engine I can garuntee the first few times you step on the gas you're gonna break leaves/axles etc.