Cam Choice...How much does engine size change it?
As I am sure you guys will agree, choosing a cam is like Christmas come early. I have put it down before but a brief review of my combo.
540, with 4.5 crank and .030 Ross flat tops, 6.8 BBC rods. The heads I am currently shopping for and will either be BT's or the Flow Technologies A46 clones, either will be out of the box with minimal work. The engine is going in a 68 Mustang, with a C6 behind, the current converter will probably flash to 3000-3200 with this engine as it is 2500 or so with my 390. The current gears are 3.50's but these can be changed.
The cam I originally planned to use was Comps smallest mechanical roller, grind number XR274R, 650/657 lift 236/242 at .050, 110 seperation. Several people have told me that on a 540 that cam will be really mild, any opinions? The next step up is a 657/664 242/248 grind, and it goes up in steps like that. Any pointers?
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Bob M
(no login)
63.25.252.219 That cam would be mild in a 460...
No score for this post September 26 2001, 1:06 AM
The most important #'s to look at when comparing cam specs are the duration @ .050" lift and lobe seperation. For your combo I recommend a cam with the duration @.050" in the 260* range with 108* seperation.
The only draw-back to running a solid roller in a street car with those duration #'s is that most grinds are above .700" lift and fairly hard on valve-springs.
Ultradyne makes some in that range with lift below .700" and I will probably use one of theirs. I have run their solid flat-tappet grinds in the past with much success.
http://ultradyne.com
Bob
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67f100
(no login)
216.224.166.140 Check out this cam combo for a 460, and give me some feedback please...
No score for this post September 26 2001, 2:17 AM
In an earlier post, I worked this up on Desktop Dyno. The motor would be used in a 67 F100 pickup, with a C6 and a 2500 rpm converter, and 3.73:1 gear ratio. The truck weighs 4150 lbs. right now with the stock 352 ci. engine in it.
1) 460 +.030
Edelbrock Aluminum heads (used the flow figures)
Crane Hydraulic Roller cam 359351 .590/.614 lift 290/300 Duration - 114 deg.LC
10.20 Comp.
Large tube headers with mufflers
Dual plane manifold
870 Holly Avenger Carb.
=527 hp 503 ft.lbs torq. @ 5500 rpm
* Retarded the cam 2 degree's
=530 hp 463 ft.lbs torq. @ 6000 rpm
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RJP
(no login)
198.81.16.54 Comp Cams
No score for this post September 26 2001, 1:04 PM
Here is a flat tappet cam I run in a long rod 514 with alum. CJ heads and 2 850 d/p Holleys: Lift-.690" in. -.678" ex. Dur @ .050" 276 deg in. 283 deg ex. 112 deg l/s. This was done by the dyno shop at Comp Cams, not a shelf cam. Grind # FF 6268/320S-1 FT112 I run this in a Howard flatbottom, so far I am pleased with the cam but haven't had the time to really get the boat combo. dialed in.
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67f100
(no login)
216.224.148.212 Thanks RJP...what's you're opinion of the Crane cam?...
No score for this post September 27 2001, 12:50 AM
the Comp cam you designed looks pretty stout for the street. I want all the horsepower I can get, but I don't want to have to have a flight engineer along to help me drive it down the road! I'd like to hear from you about it.
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67f100
(no login)
216.224.148.212 A little PS...A Howard flat bottom eh?...that ought to get the old blood going!
...n/m
No score for this post September 27 2001, 12:53 AM
...
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RJP
(no login)
198.81.16.172 Crane Cams?
No score for this post September 27 2001, 7:23 PM
If I can't get what I want from the dyno shop at Comp then Crane would be my next choice, they grind some nice cams and I've never been dissapointed. The last Crane I ran was in a 466" BBF in the same Howard flat. I don't remember the specs but if you are interested I can find the card. It also is a flat tappet. The only reason I don't run solid rollers is I have to deal with no wake/5 mph zones and long periods of idling and that will kill the cam/rollers. I never thought of using hyd. rollers.
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Chris C
(no login)
168.73.245.58 Cam selection
No score for this post September 26 2001, 7:34 AM
I agree, that cam is small for the 540. I'd run something in the 250* area, it would still match your convertor well. I imagine you'll stall more than 3000rpm btw, probably closer to 3500rpm. The 3.50 will probably work out ok too, I'd definitely wait to change it.
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Gary
(no login)
12.13.226.12 Cam Choice
No score for this post September 26 2001, 12:59 PM
First thing You need to know is blue thunder heads require special headers the exhaust side of their heads aren't 90 degrees from the head gasket area just one more cost to consider.Back to cams My 514 has a comp cams 259int 269ex 680lift intake and 680lift exhaust 110 separation with new cj heads a 3000 stall converter and 3.70 gears. Its very mild the little bit I have driven the car on the street it has no problem.This thing makes so mach low end I don't know how you can hurt it .
540, with 4.5 crank and .030 Ross flat tops, 6.8 BBC rods. The heads I am currently shopping for and will either be BT's or the Flow Technologies A46 clones, either will be out of the box with minimal work. The engine is going in a 68 Mustang, with a C6 behind, the current converter will probably flash to 3000-3200 with this engine as it is 2500 or so with my 390. The current gears are 3.50's but these can be changed.
The cam I originally planned to use was Comps smallest mechanical roller, grind number XR274R, 650/657 lift 236/242 at .050, 110 seperation. Several people have told me that on a 540 that cam will be really mild, any opinions? The next step up is a 657/664 242/248 grind, and it goes up in steps like that. Any pointers?
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Author Reply
Bob M
(no login)
63.25.252.219 That cam would be mild in a 460...
No score for this post September 26 2001, 1:06 AM
The most important #'s to look at when comparing cam specs are the duration @ .050" lift and lobe seperation. For your combo I recommend a cam with the duration @.050" in the 260* range with 108* seperation.
The only draw-back to running a solid roller in a street car with those duration #'s is that most grinds are above .700" lift and fairly hard on valve-springs.
Ultradyne makes some in that range with lift below .700" and I will probably use one of theirs. I have run their solid flat-tappet grinds in the past with much success.
http://ultradyne.com
Bob
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
67f100
(no login)
216.224.166.140 Check out this cam combo for a 460, and give me some feedback please...
No score for this post September 26 2001, 2:17 AM
In an earlier post, I worked this up on Desktop Dyno. The motor would be used in a 67 F100 pickup, with a C6 and a 2500 rpm converter, and 3.73:1 gear ratio. The truck weighs 4150 lbs. right now with the stock 352 ci. engine in it.
1) 460 +.030
Edelbrock Aluminum heads (used the flow figures)
Crane Hydraulic Roller cam 359351 .590/.614 lift 290/300 Duration - 114 deg.LC
10.20 Comp.
Large tube headers with mufflers
Dual plane manifold
870 Holly Avenger Carb.
=527 hp 503 ft.lbs torq. @ 5500 rpm
* Retarded the cam 2 degree's
=530 hp 463 ft.lbs torq. @ 6000 rpm
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
RJP
(no login)
198.81.16.54 Comp Cams
No score for this post September 26 2001, 1:04 PM
Here is a flat tappet cam I run in a long rod 514 with alum. CJ heads and 2 850 d/p Holleys: Lift-.690" in. -.678" ex. Dur @ .050" 276 deg in. 283 deg ex. 112 deg l/s. This was done by the dyno shop at Comp Cams, not a shelf cam. Grind # FF 6268/320S-1 FT112 I run this in a Howard flatbottom, so far I am pleased with the cam but haven't had the time to really get the boat combo. dialed in.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
67f100
(no login)
216.224.148.212 Thanks RJP...what's you're opinion of the Crane cam?...
No score for this post September 27 2001, 12:50 AM
the Comp cam you designed looks pretty stout for the street. I want all the horsepower I can get, but I don't want to have to have a flight engineer along to help me drive it down the road! I'd like to hear from you about it.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
67f100
(no login)
216.224.148.212 A little PS...A Howard flat bottom eh?...that ought to get the old blood going!
...n/mNo score for this post September 27 2001, 12:53 AM
...
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
RJP
(no login)
198.81.16.172 Crane Cams?
No score for this post September 27 2001, 7:23 PM
If I can't get what I want from the dyno shop at Comp then Crane would be my next choice, they grind some nice cams and I've never been dissapointed. The last Crane I ran was in a 466" BBF in the same Howard flat. I don't remember the specs but if you are interested I can find the card. It also is a flat tappet. The only reason I don't run solid rollers is I have to deal with no wake/5 mph zones and long periods of idling and that will kill the cam/rollers. I never thought of using hyd. rollers.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Chris C
(no login)
168.73.245.58 Cam selection
No score for this post September 26 2001, 7:34 AM
I agree, that cam is small for the 540. I'd run something in the 250* area, it would still match your convertor well. I imagine you'll stall more than 3000rpm btw, probably closer to 3500rpm. The 3.50 will probably work out ok too, I'd definitely wait to change it.
Score 1 2 3 4 5 (5=Excellent) Edit Message Delete Message Lock Thread Respond to this message
Gary
(no login)
12.13.226.12 Cam Choice
No score for this post September 26 2001, 12:59 PM
First thing You need to know is blue thunder heads require special headers the exhaust side of their heads aren't 90 degrees from the head gasket area just one more cost to consider.Back to cams My 514 has a comp cams 259int 269ex 680lift intake and 680lift exhaust 110 separation with new cj heads a 3000 stall converter and 3.70 gears. Its very mild the little bit I have driven the car on the street it has no problem.This thing makes so mach low end I don't know how you can hurt it .
