I know this has bee done a million times before on this site but it's easier to get info from guys who've done this before straight up rather then looking/seaching in old posts. So here goes...

I have a 383 roller block with speed pro hyper dome pistons, eagle "sir" rods, scat 9000 crank, all new plugs and seals etc. My heads are World Sportsman II's with port/bowl work, 64cc chambers and 200cc runners. The intake is the Sportsman II dual plane but I might swap that out for a RPM Air Gap. I was using 1.6 roller rockers on my old 357ci (XE284 cam with same top end) so those will be used again for the roller motor. My question is, what cam to run with this beast? It will be more for street duty but sometimes hit a track up. Reading some posts, most people like the XR288HR cam. The specs are pretty much close to my old XE284 with more lift. Using the 1.6 rockers, that should net me around .550/.570 with the XR288 right? My trans is a 700R4 with 3k stall for now but I plan on a 6spd conversion next year. My rear gears are 3.70's. How would this cam work? Would my brakes suffer like my XE284 made them? Any other cam choices out there that would work better? This cam is quite expensive too but if it's the best for my application, money is no object to a certain degree. My carb is a Holley 650P but I plan on switching that for a BG Speed Demon 750. Thanks in advance.

Wasn't planning on a motor swap anytime soon but my 10psi of oil pressure and scored cylinder walls and crank made me think of getting a new motor so why not go roller?

 

i like my custom grind. its a large split 230/245. not the best for the n/a and heads i have i think but it will scream on spray still does good on motor
the 288HR should perform as good in my motor if not a tad bit better. hard to say they are pretty close cams.

i'd go with the air gap intake and either the 282hr or 288 if you want a comp cam. 282 is more streetable and i'd lean that way if your worried about brakes. the 288 will have a softer feel on the brakes but will still work. my car is pretty tame for a mid 11 second car but the brakes are a touch soft due to my tight 109 lsa. 288 may have abit better feel to the brakes than my cam.

another good one is crane/gm 847 grind. as aggressive if not a touch more aggressive than the 288hr even tho the duration at .050 is abit less. dont let that fool you that cam loves to rev up plus the exhaust split should help alittle on those heads as i dont think they have a great exhaust port to intake port flow ratio

also look into the cc306..old but very good grind that still works on most motors

my cam peaked at 6300 rpms about. 288 should do the same and 847 cam as well if not higher.

depends on your goals tho, if you want less rpm and more streetable something like 230/236 of that 282hr is nice, same with the cc306

 

Streetable has become more apparent after driving my car with the XE284. Even though it sounded absolutely awesome, driving it around town in stop and go traffic it wasn't very forgiving. I wanted to make this motor powerful and sound even more mean but with the way I use this car it might be better off to just run the XR282 and keep my sanity. PM'd a few guys on here to ask them about their XR282 383's. See what comes up. Are there any cams out there that give the same duration/lift but are on a 112 to 114 LSA? Thanks dude, figured you would post in here at some point.

EDIT: Click Here for cam specs

I LOVE this cam. Any thoughts?

 

i was just gonna say the XFI cam is a nice 230/236 cam with a wider LSA. you can even order a 288HR version thats on a 113 lsa. that will help alittle with the idle and give vacuum. but the XFI cam will make it a powerful car and retain a good idle. Just needs good valve springs to handle the aggressive lobes

 

I am running the comp 282 cam on a 112 lsa with 1.5 crane gold RR's. This is in a stock bore, pistons, rods and crank L98 motor. I am running a th350 with a 3500 converter, 3.73 gears and a 26" tall tire.

This cam is very streetable in my 350. I think the 112 lsa helped a bit. My stock brakes work just fine.
OH yeah, I am running 750 Holley Street HP carb with RPM airgap intake and AFR190 heads.

Go with a Holley carb, I had a Speed Demon on the car and couldnt get it to work as good as a holley 750 vs carb I had.

 

I have double springs as it sits now. Should be good for .600 lift. Think I should get something bigger just in case? Whats the spec on the 288HR XFI cam. I looked it up but couldn't find anything. Part/Grind number?

 

they have lobes for it but do not list it as off the shelf grind. i dont think it costs extra since its not a whole redesign but it may have an extra cost as a custom grind

its basically the 288hr with 236/242 duration but with .57x+ lift and 113 lsa

forgot to mention comp cams has the 282 and 288 hr's listed as 110 lsa's but you can get 112's

thunderracing sells the 112 version

 

I think I will be going with the 280XFI cam. Thanks for the help dude. Get your car running better?

My intake will eventually be the RPM air gap. Do you think my 650 double pumper will be enough for this?

 

naw, i think a 750 atleast will be best for that motor. 650 will work for now but i'd look into upgrading someday for best power

 

I run a 288 with 1.6 and N/A it made good power. Streetablility wasnt bad with a 3000 stall, stock drum brakes were crap, but since I upgraded to LT1 discs, they're fine.

Wish I would've gotten the 112 or 113 lsa, would see more boost.

 

Yeah the idea was to keep this carb until I need it but once that happens I'll be switching to a BG 750.