Hello thanks for lookin.I have a 76 cordoba with verry low miles it runs great but... first off im gasket matching every thing,using 67 383 manifolds i heard there better than mine and they will be cleaned up inside alittle,into 2.5 dualexhaust and just rebuilt the TQ will a 204-214 270-280 .420-.443 cam be a good choice im using all stock comp, they are in good shape with only 56,000 on them. The idea is to get a little more thats all!! Thanks for any help or suggestions.   AG      

I would step up the mopar 268/284 Cam it will give you about 40-50 more hp and have great streetability and vacuum (It's the same cam used in the 383HP and 440 six packs. Another option is the Comp cams XE-268 cam it will give you about 390-400hp with the stock components and is very streetable like the mopar six pack cam. If you reaLLY WANT TO GET WILD use the Mopar solid 284/525 cam. You would need an adjustable rocker and the vacuum will drop to about 11" in a 400 motor, but it will produce about 475-480 hp with the current setup.
Mike

Thanks for your input,is the 400 really able to make that kinda power with just a cam basicaly?not being smart, never owned a mopar and thought it was a 318 in sheeps clothing,well if so ill be mighty suprised.Thanks again    A G  

Arnold: Are you kidding... the 400 motor can produce gobs of HP. The main problem with stock 400's was poor compression 7.5/1 and lousy cam. The heads are great and the large bore and stiff cylinder walls make for a potentially great motor. The only thing a 400 lacks in comparison with a 440 is torque potential. Raise the compression to 9.5/1, cam it and it will produce more than enough power.  

Really,would you know off the top of your head if a set of 66 383 heads would have smaller cc's giveing me a better comp ratio,the 76 has like 8.1 or so, what would they be with the other heads?if you know off the top, please post.      A G

Arnold:
If the 66 383 heads are 516's they have a 77-78cc chamber, plus it is closed chamber design which is much better. They are adequate for a 400, but you really need larger valves (2.14/1.81) if you go much beyond 224 degrees duration @ .050" with the cam.
Mike  

Arnold: Off the top of my head, I would guess the compression ratio would be around 9.0-9.2/1 with the 1966 383 heads. The more important issue is cylinder pressure (you want it in the range of 160-180psi with a cam in the range of 224-235 degrees @ .050" lift.
Mike  

Hey thanks for the help, im looking into the 383 heads in the garage to find out about them and if they help comp im going to use them and the cam has been paid for its the 204-214-270-280-420-443.  112sep thats going to be a big diffrence in it self and thats all i want plus with dualexhaust its going to sound a little better im going to be happy.Just installed ALL new suspention and shocks just got in and it rides better than new i would think.In 2 weeks im doing the motor it will take a month or so before im done i like to take my time and do it wright the first time,and let ya know how it goes .  A G  

Arnold:
That cam will produce gobs of torque and the 112 degree Lobe seperation a smooth idle. Suprisingly, the six pack cam used in 1970 383HP, 440 HP and 440 6-packs was: 268/284 Degrees (224/241 degrees duration @ .050" lift) and had a whooping 114 degree lobe seperation (It idles smooth, but had a mean growl when reving up).
Mike  

that 76 400 has thicker main webbing then all other mopar engines besides the earlier 230 and 630 blocks ,also the  75 76 440s had thicker webbing but not near as much as the early 400s I have several of the pre 73 630 and 230 blocks and comparing them to a 68 383 in the webbing around the mains is a joke.later 400s had thinner walls but your engine can handle 450 hp all day long as far as block strength over 450 I use half fill with block filler.440 source.com  

Mikes on the money , dont be afraid to push for even more hp with that block as its plenty stout.For the street I like the lunati 305 voodoo hyd dual pattern cam .duration 284 292 at .050 242 intake 252 exhaust. take that 383 crank and stuff it into the 400 and with this cam and proper components with stock stroke can make a good 525 550 hp easily.10 or 10.5 compression get ya there. if required mill the heads to get proper compression.make us proud arnold  

sorry, lift is .533 intake and .552 exhaust with 1.5 ratio and this cam has super fast ramps  

just thought i would bring your attention that this thread was last posted in feb 2005. hes probably been through 2 motors by now.    

hey. running a 465/488 lift summit cheapie cam in a 400 cast crank w stock intake, thermoquad, and headers/slightly ported heads. In a 78 3/4 ton truck with dana 60 posi, 4.10.
no traction prob, as the cam bleeds off cylinder pressure at low rpms, but it runs 2 car lengths behind a 13.40 dart w a 383 and 4 spd. when I get a converter, I'll post times.  and- ya the dart was sick..fuel probs.  

I like the 214 181 valves with this combo hahaha stop whining big, its all about fun bro.