mopar cam shafts

[dcred]

ok i'm a little confused on cam sizes iwas going to use mopar cam purple 284/284 484/484 @ 108 but i was told i would'nt have much vac for the car ---- i have power brakes and a EFI FAST fuel system auto trans 3.91 gears torque converter around 2600 - 2800 the moter is ( 440 bored .30 over compression about 9.8 ) stock heads with port matching done on the heads Manci racing tells me i need 284/284 484/484 @114 ????? is this cam streetable and have good vac and go to the track ones awhile . i called comp cams tech they tell me it wont work on my set up they suggested 230/236 488/491 @ 110 .....i want to go with the purple cam any thoughts would be great ..

 

[BLK 68 R/T]

Are you running headers or stock iron manifolds?

 

[dcred]

undecided ?

 

[BLK 68 R/T]

So, I'm far from a cam expert but have learned enough over the last few months while researching my own engine build to throw in my 2 cents

With the FAST efi, which I also have, I was advised to stay with a cam with a duration in the low to mid 230's @ .050 duration. If you are going to run headers then the 110 and down LSA will be fine. If, however, you are going to run iron manifold you will want a cam with a large LSA 112 and up to help scavenge the cylinders. With that said, if you end up going headers the .488/.491 @ 110 cam would be my choice for an off the shelf cam. I had on in my 68 GTX and it made good vacuum for my power brakes. Otherwise I would be looking at a custom ground cam specifically tailored to your application.
Hope this helps.
Wes

 

[SlinktRR]

undecided ?

If undecided on headers dont use the MP .484. This cam needs 3000 stall, headers, 3.91's and 10.5:1 compression to be really happy. And you will not have any vacuum to speak of, maybe 10 at most even with the 440. It's fun over 3000 RPM.. but only over 3000. I like it but I have manual brakes and a 3000 stall converter on a 70RR. And streetable is a very relative term, it's more defined by what you are willing to tolerate.

Try something like the lunati 60303 or cam with similar specs. A guy on FABO replaced his 383's purple cam with the 60302 grind lunati and the story had a nice ending, I think he has 16" vacuum...compared to the 9 he had before with the 484.

If you want purple and manifolds you could go with the .528 solid on the 440 which is popular to use with stock exhaust manifolds and it gives good vacuum with the 112 LSA.

 

[BLK 68 R/T]

I agree with the above if you are interested in going the solid cam route. I forgot to mention Crower, they have a few cams that would fit the bill as well.

 

[pentahead]

My 383 with the .484 purple pulls 12" vacuum.....

 

[RT K_line]

I've used the solid 296 557 solid purple shaft and didn't have any problems with my power brakes so that cam should work ok. I think that cam was in my R/T when I bought it too.

 

[dcred]

thanks for everybodys input i chose to go with comp cam high energy 21-224-4

 

[YY1]

I ran the 284/484 in a 70 383 with 9.5:1, 3:55 gears and a stock converter.

Dialing in the carb was a bitch but after that it was fine.

It was a bit happier over say 2500 RPM, and I didn't have power brakes.

I believe it can be done.