I am moving this post to its own topic, all are welcome to contribute
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Are these cams (1) and cam (2) a better choice for the 4v now over the 114 lobe separation cobra jet cam (3) thanks
(1) Custom hydraulic flat tappet cam ground by Bullet Cams (lobes H270/306 and H290/312), spec: 270°/290° duration @ 0.006, 222°/240° duration @ 0.050, 0.521/0.531 net lift, 105°/115° lobe centerlines, 110° lsa, 60° overlap, EVO = 80°, IVC = 60°. Speed Pro HT900 hydraulic flat tappets.
(2) Custom hydraulic flat tappet cam ground by Bullet Cams (lobes HF275/328 and H286/328), spec: 275°/286° duration @ 0.006, 223°/230° duration @ 0.050, 0.559/0.559 net lift, 103°/117° lobe centerlines, 110° lsa, 60.5° overlap, EVO = 81°, IVC = 60.5°. Speed Pro HT900 hydraulic flat tappets
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(3) Intake Lobe: #HF275/328 (CRA, designed for Ford 0.875 tappets)
Intake lobe mathematic centerline = 112° ATDC
Exhaust Lobe: #H287/3283 (CRA)
Exhaust lobe mathematic centerline = 116° BTDC
114° lobe separation angle (camshaft degrees)
---------------------------------
Exhaust valve opening = 79.5° BBDC
Intake valve opening = 25.5° BTDC
53° overlap
Exhaust valve closing = 27.5° ATDC
Intake valve closing = 69.5° ABDC
---------------------------------
275° advertised intake lobe duration
223° intake lobe duration at 0.050"
Intake lobe hydraulic intensity = 52
0.567" theoretical intake valve lift (1.73 rocker ratio)
---------------------------------
287° advertised exhaust lobe duration
235° exhaust lobe duration at 0.050"
Exhaust lobe hydraulic intensity = 52
0.568" theoretical exhaust valve lift (1.73 rocker ratio)
---------------------------------
(1) Custom hydraulic flat tappet cam ground by Bullet Cams (lobes H270/306 and H290/312), spec: 270°/290° duration @ 0.006, 222°/240° duration @ 0.050, 0.521/0.531 net lift, 105°/115° lobe centerlines, 110° lsa, 60° overlap, EVO = 80°, IVC = 60°. Speed Pro HT900 hydraulic flat tappets.
(2) Custom hydraulic flat tappet cam ground by Bullet Cams (lobes HF275/328 and H286/328), spec: 275°/286° duration @ 0.006, 223°/230° duration @ 0.050, 0.559/0.559 net lift, 103°/117° lobe centerlines, 110° lsa, 60.5° overlap, EVO = 81°, IVC = 60.5°. Speed Pro HT900 hydraulic flat tappets
----------------------------------
(3) Intake Lobe: #HF275/328 (CRA, designed for Ford 0.875 tappets)
Intake lobe mathematic centerline = 112° ATDC
Exhaust Lobe: #H287/3283 (CRA)
Exhaust lobe mathematic centerline = 116° BTDC
114° lobe separation angle (camshaft degrees)
---------------------------------
Exhaust valve opening = 79.5° BBDC
Intake valve opening = 25.5° BTDC
53° overlap
Exhaust valve closing = 27.5° ATDC
Intake valve closing = 69.5° ABDC
---------------------------------
275° advertised intake lobe duration
223° intake lobe duration at 0.050"
Intake lobe hydraulic intensity = 52
0.567" theoretical intake valve lift (1.73 rocker ratio)
---------------------------------
287° advertised exhaust lobe duration
235° exhaust lobe duration at 0.050"
Exhaust lobe hydraulic intensity = 52
0.568" theoretical exhaust valve lift (1.73 rocker ratio)
---------------------------------
Hi Rich
My understanding of your application is a "351c 4v flat top pistons quench camber heads automatic trans". Your engine shall have about 9.5:1 compression ratio or more, depending upon the piston's compression height, the head gasket's compressed thickness, the head casting (D0AE or D1AE), the deck height (9.215 or less), and the bore diameter. It would be helpful to have a more precise number.
Cams 1 & 2 close the intake valve at 60° ABDC and are intended for an engine with less static compression than yours. Your engine will need a camshaft that closes the intake valve around 70° ABDC; with a more precise figure for the engine's static compression I can be more precise in helping you.
I know you've been unhappy with past choices in camshaft, I assume you're looking for better drivability? Your current Lunati cam (hydraulic flat tappet) has the following specs:
275°/290° duration at 0.006 (advertised)
225°/240° duration at 0.050
0.550/0.560 gross valve lift
110° LSA
106° ICL
_____________________________________
Seated valve events @ 0.006
EVO = 79° BBDC
IVO = 31.5° BTDC
Overlap = 62.5°
EVC = 31° ATDC
IVC = 63.5° ABDC
That IVC would work with 9.6:1 static compression or less
The amount of overlap and the intake valve opening (IVO) dictate drivability. I think you'll be happiest with a camshaft having 55° overlap or less. You'll also be happier with 114° LSA than 110° LSA. And because the engine has 4V heads it needs a dual plane intake manifold with a full height plenum divider.
I could use two bits of information from you, (1) a more accurate number for the static compression, and (2) what rev limit have you set the engine for, 6200 rpm or 7200 rpm?
My understanding of your application is a "351c 4v flat top pistons quench camber heads automatic trans". Your engine shall have about 9.5:1 compression ratio or more, depending upon the piston's compression height, the head gasket's compressed thickness, the head casting (D0AE or D1AE), the deck height (9.215 or less), and the bore diameter. It would be helpful to have a more precise number.
Cams 1 & 2 close the intake valve at 60° ABDC and are intended for an engine with less static compression than yours. Your engine will need a camshaft that closes the intake valve around 70° ABDC; with a more precise figure for the engine's static compression I can be more precise in helping you.
I know you've been unhappy with past choices in camshaft, I assume you're looking for better drivability? Your current Lunati cam (hydraulic flat tappet) has the following specs:
275°/290° duration at 0.006 (advertised)
225°/240° duration at 0.050
0.550/0.560 gross valve lift
110° LSA
106° ICL
_____________________________________
Seated valve events @ 0.006
EVO = 79° BBDC
IVO = 31.5° BTDC
Overlap = 62.5°
EVC = 31° ATDC
IVC = 63.5° ABDC
That IVC would work with 9.6:1 static compression or less
The amount of overlap and the intake valve opening (IVO) dictate drivability. I think you'll be happiest with a camshaft having 55° overlap or less. You'll also be happier with 114° LSA than 110° LSA. And because the engine has 4V heads it needs a dual plane intake manifold with a full height plenum divider.
I could use two bits of information from you, (1) a more accurate number for the static compression, and (2) what rev limit have you set the engine for, 6200 rpm or 7200 rpm?
More info. Flat tops , Compression height is 6.645 Speed Pro Hypereutectic pistons 4.030 bore ,or possibly forged 1.647 , my heads seem to be the 62.8 chamber casting # DOAE ,using felpro 1013 head gaskets Thickness: .041" bore 4.100 , unsure if the heads has ever been milled or the block decked , I’ll just have to believe they have not .the carb is a 750 vacuum secondary , the intake is a offenhauser 360 degree part # 5964 , if this intake is junk tell me what I need to get. Car has a 3:00 rear gear , TCI 10 inch street fighter torque converter maybe 2200 stall the lunati cam made the engine diesel when cutting the ignition off , the engine kept trying to run , and the motor just seemed weak and run out of steam pretty quick , may have been a valve spring issue
I had a crane 284 H12 part# 13305 228-228 @.050 112 lobe sep and it didn’t perform well either , I’m not dead set on a rpm peak , not sure what the limits of a hydraulic camshaft is
Thanks
I had a crane 284 H12 part# 13305 228-228 @.050 112 lobe sep and it didn’t perform well either , I’m not dead set on a rpm peak , not sure what the limits of a hydraulic camshaft is
Thanks
This is a new build, old motor dropped a Manley exhaust valve , it had flat top aftermarket Badger brand pistons ,I’m using the same heads on new build
Here is my 2 cents worth. I don't think you or anyone else can go on someone else's pick of a cam.
It's like your Mother picking a girl friend for you?
You can just probably stay in yourpier peer group, i.e., hydraulic roller, street sleeper, track killer, original heads, maximized headers under the chassis...ok, I gotta' stop...this is getting very suggestive and getting me all excited with these naughty thoughts.
I'll be back after I take a shower.
It's like your Mother picking a girl friend for you?
You can just probably stay in your
I'll be back after I take a shower.
Thank youquote:Originally posted by George P:
Hi Rich
My understanding of your application is a "351c 4v flat top pistons quench camber heads automatic trans". Your engine shall have about 9.5:1 compression ratio or more, depending upon the piston's compression height, the head gasket's compressed thickness, the head casting (D0AE or D1AE), the deck height (9.215 or less), and the bore diameter. It would be helpful to have a more precise number.
Cams 1 & 2 close the intake valve at 60° ABDC and are intended for an engine with less static compression than yours. Your engine will need a camshaft that closes the intake valve around 70° ABDC; with a more precise figure for the engine's static compression I can be more precise in helping you.
I know you've been unhappy with past choices in camshaft, I assume you're looking for better drivability? Your current Lunati cam (hydraulic flat tappet) has the following specs:
275°/290° duration at 0.006 (advertised)
225°/240° duration at 0.050
0.550/0.560 gross valve lift
110° LSA
106° ICL
_____________________________________
Seated valve events @ 0.006
EVO = 79° BBDC
IVO = 31.5° BTDC
Overlap = 62.5°
EVC = 31° ATDC
IVC = 63.5° ABDC
That IVC would work with 9.6:1 static compression or less
The amount of overlap and the intake valve opening (IVO) dictate drivability. I think you'll be happiest with a camshaft having 55° overlap or less. You'll also be happier with 114° LSA than 110° LSA. And because the engine has 4V heads it needs a dual plane intake manifold with a full height plenum divider.
I could use two bits of information from you, (1) a more accurate number for the static compression, and (2) what rev limit have you set the engine for, 6200 rpm or 7200 rpm?