picking a new cam over winter any ideas

[464elcamino]

Kinda looking at the 11-602-4 [94] 295th7 comp cam or 11-250-3 xe284h comp cam. Whats everone else running in there BBC build?

specs for xe284h are
Cam Style Hydraulic flat tappet
Basic Operating RPM Range 2,300-6,500
Intake Duration at 050 inch Lift 240
Exhaust Duration at 050 inch Lift 246
Duration at 050 inch Lift 240 int./246 exh.
Advertised Intake Duration 284
Advertised Exhaust Duration 296
Advertised Duration 284 int./296 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.574 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.578 in.
Valve Lift with Factory Rocker Arm Ratio 0.574 int./0.578 exh.
Lobe Separation (degrees) 110



295th7 specs are
2,300-6,200
Intake Duration at 050 inch Lift 243
Exhaust Duration at 050 inch Lift 257
Duration at 050 inch Lift 243 int./257 exh.
Advertised Intake Duration 295
Advertised Exhaust Duration 312
Advertised Duration 295 int./312 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.522 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.507 in.
Valve Lift with Factory Rocker Arm Ratio 0.522 int./0.507 exh.
Lobe Separation (degrees) 107
Camshaft Gear Attachment 3-bolt
Computer-Controlled Compatible No
Grind Number 295TH7

 

[lilbowtie]

You need to look at your complete package and what your using it for - it's all got to work together.

 

[bracketchev1221]

One point to consider going from a hydraulic to a solid is that comparing the 2 cams a solid needs to be slightly bigger to have the same numbers as a hydraulic. This is due to the valve lash of the solid. But like I said previously, and the above poster hinted at, you need to straighten out the rest of the engine first. The carb is way too big, and with 12-1 compression, it needs a MUCH larger cam.

 

[464elcamino]

Its going to be a street/strip like my elcamino but mainly strip. Why is the carb an issue ? I use the same one on my 12.5:1 464 BBB with a way smaller cam and picked up .3 in the 1/4 over a 850 DP. I mean I have an 850 I can use that I had on my Elco, but with this being bigger I figured the 1050 would help it aswell and the throttle response improved drastically with the 1050. ANd both the cams listed are Hyd. I dont like the hassles of the solid lifts. And the comp ratio on this one is around 11.5 to 11.8:1.
All input is welcome .

Heads are mild ported 781 with lunati roller rockers, 11.8:1 comp ratio, 1050 dom carb or an 850 dp on a holley track dominator hi rise single plane int., 2 1/8" primary long tube headers, stg3 400th, 3500 stall, 4.11's .

What cam do you suggest Bracketchev1221 ?

 

[lilbowtie]

I'm with bracketchevy you can use more cam than you picked. My suggestion would be something around a 600 lift w/ about 260 dur @50 on a 110 lobe center. I personally like the 306S grind the Comps cams has. I know you don't like solid cams but they are really not a hassle. I run the points chase and have done nothing but check them twice a year.

 

[bracketchev1221]

I wouldn't be too concerned about going to a solid cam. At most, you check the rockers twice a year and then run the hell out of it. I would look at the Lunati 40225 cam, the 40227 may be too big, or something like the Crane 131311. The reason I say the carb is too big is because I didn't run a 1050 dominator until my 509 which dynoed at 780 and went 9.50's in my car at 3160 lbs shifting at 7400 and crossing at 7500. I ran an 850 on my +.060 427 (440) going 10.30's with 1.42 60 ft times at 130 mph weighing 3360. If you picked up 3 tenths going from 11.70's to 11.40's there was something seriously wrong with the carb. An 850 with smaller butterflies in a foot brake car should be much more responsive than a dominator. I think a converter change to 44-4500 rpm will also help you to get the heavy car moving. Your heads will probably run out steam about 6800-7000 so I think that should become your target rpm. Good luck. I bet you can get thing in the 10's without much effort.

 

[464elcamino]

Thanks Guys will use all this info and keep ya updated.

 

[464elcamino]

Heres what comp cams selected for me. What do you guys think?

Brand COMP Cams
Manufacturer's Part Number 11-606-5
Part Type Camshafts
Product Line COMP Cams Drag Race Camshafts
Summit Racing Part Number CCA-11-606-5
UPC 36584030249

Cam Style Mechanical flat tappet
Basic Operating RPM Range 3,500-6,500
Intake Duration at 050 inch Lift 256
Exhaust Duration at 050 inch Lift 264
Duration at 050 inch Lift 256 int./264 exh.
Advertised Intake Duration 283
Advertised Exhaust Duration 291
Advertised Duration 283 int./291 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.578 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.578 in.
Valve Lift with Factory Rocker Arm Ratio 0.578 int./0.578 exh.
Lobe Separation (degrees) 108
Computer-Controlled Compatible No
Grind Number CB MA283A-8
Valve Springs Required Yes
Quantity Sold individually.

 

[prairiehotrodder]

why not a roller? Your leaving power on the table with a flat tappet cam. BBC's love big solid roller cams! I agree with lilbowtie, 260 @.050 and .600 lift or more on 110 LSA. Especially since you have lots of gear. I wouldn't be afraid to try a 108 LSA as well, they sound better and really turn on harder.
brian

 

[bracketchev1221]

It is a good choice, I would just have liked to see more lift. You have more lift with the hydraulic in the car now since the solid has a lash clearance. Look at the Lunati 40225 and see how the duration numbers match up but it gives you .050 more lift. That was one of the reasons I didn't pick a Comp Cam for you. Either the duration got too high, or the lift was too low. That Comp Cam has a good duration range though.