Overlap and Valve Events Editorial
#82
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Great information, hope this thread is not dead because I’m trying to figure out how far off base I may be. I’ve got a ‘64 Malibu restomod project that is taking me forever to finish. I’ve got a 408 iron block with unported 823s, stock intake and FAST 92 TB. I considered aftermarket heads and may end up there eventually but I decided to spend money on the stuff I couldn’t change easily in a few hours (ie forged 4” stroke).
My goals are a weekend toy I can drive 300-400 miles to events and still get into the 10s. I want a rough idle because I think that’s how muscle cars should sound (I had the old 280/480 cam in my 283). The car may never see the track but I can’t let my wife’s gen vi outrun me. I talked with BTR about their stroker cam and talked with Martin as well. However when my machine shop was ordering the cam I couldn’t track Martin down so I told them my goals and where I thought the cam should be. They worked out the details with comp. what I ended up with was a 231/241 605/613 cam
with valve events of:
intake 5 BTDC 47 ABDC
exhaust 56 BBDC 6 ATDC
On the surface I think the cam is too small for this motor but when I look at the cams spin monster does maybe it’s not. The other thing odd is I’ve never seen anyone use these lobes in this forum. The lobes are 13777R/13782R which is some kind of marine lobe.
My goals are a weekend toy I can drive 300-400 miles to events and still get into the 10s. I want a rough idle because I think that’s how muscle cars should sound (I had the old 280/480 cam in my 283). The car may never see the track but I can’t let my wife’s gen vi outrun me. I talked with BTR about their stroker cam and talked with Martin as well. However when my machine shop was ordering the cam I couldn’t track Martin down so I told them my goals and where I thought the cam should be. They worked out the details with comp. what I ended up with was a 231/241 605/613 cam
with valve events of:
intake 5 BTDC 47 ABDC
exhaust 56 BBDC 6 ATDC
On the surface I think the cam is too small for this motor but when I look at the cams spin monster does maybe it’s not. The other thing odd is I’ve never seen anyone use these lobes in this forum. The lobes are 13777R/13782R which is some kind of marine lobe.
#83
FormerVendor
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Crower Cams 105 C/L
Hi 64SS, I have had Crower Cams make me the 232/242 spec you ask about on a 105 C/L.
This has the"sound" of a TDF !
This application was for Off Road Racing.
I could order this for your needs ?
Lance
This has the"sound" of a TDF !
This application was for Off Road Racing.
I could order this for your needs ?
Lance
#84
Great information, hope this thread is not dead because I’m trying to figure out how far off base I may be. I’ve got a ‘64 Malibu restomod project that is taking me forever to finish. I’ve got a 408 iron block with unported 823s, stock intake and FAST 92 TB. I considered aftermarket heads and may end up there eventually but I decided to spend money on the stuff I couldn’t change easily in a few hours (ie forged 4” stroke).
My goals are a weekend toy I can drive 300-400 miles to events and still get into the 10s. I want a rough idle because I think that’s how muscle cars should sound (I had the old 280/480 cam in my 283). The car may never see the track but I can’t let my wife’s gen vi outrun me. I talked with BTR about their stroker cam and talked with Martin as well. However when my machine shop was ordering the cam I couldn’t track Martin down so I told them my goals and where I thought the cam should be. They worked out the details with comp. what I ended up with was a 231/241 605/613 cam
with valve events of:
intake 5 BTDC 47 ABDC
exhaust 56 BBDC 6 ATDC
On the surface I think the cam is too small for this motor but when I look at the cams spin monster does maybe it’s not. The other thing odd is I’ve never seen anyone use these lobes in this forum. The lobes are 13777R/13782R which is some kind of marine lobe.
My goals are a weekend toy I can drive 300-400 miles to events and still get into the 10s. I want a rough idle because I think that’s how muscle cars should sound (I had the old 280/480 cam in my 283). The car may never see the track but I can’t let my wife’s gen vi outrun me. I talked with BTR about their stroker cam and talked with Martin as well. However when my machine shop was ordering the cam I couldn’t track Martin down so I told them my goals and where I thought the cam should be. They worked out the details with comp. what I ended up with was a 231/241 605/613 cam
with valve events of:
intake 5 BTDC 47 ABDC
exhaust 56 BBDC 6 ATDC
On the surface I think the cam is too small for this motor but when I look at the cams spin monster does maybe it’s not. The other thing odd is I’ve never seen anyone use these lobes in this forum. The lobes are 13777R/13782R which is some kind of marine lobe.
What transmission and rear gear do you have? If it is an automatic, what RPM stall in the converter?
#85
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Cammotion, thanks for the reply. I was thinking the same thing. I actually tried to contact you when I was ordering the cam but got in a hurry and didn’t follow up. I’ve got a T-56 close ratio, 3.70 in a 9” with a locker.
Lance, thanks for the offer but I’m still not convinced the 231/241 is big enough. The motor is assembled but not installed. I don’t mind changing the cam but I want to make the right decision.
Lance, thanks for the offer but I’m still not convinced the 231/241 is big enough. The motor is assembled but not installed. I don’t mind changing the cam but I want to make the right decision.
Last edited by bks64SS; 04-11-2018 at 06:36 PM. Reason: Add more text
#86
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Crower Cams 105 C/L
Hi 64SS, I too agree AND with a "tight" C/L camshaft it will require a GREATER lobe duration to reach high RPM.
This type of camshaft will have the greatest average HP/Torque.
The specify larger lobes to Crower Cams is common with MY 246/252 spec as used more often in Off Road racing.
I have the ability to "dyno" your engine in a computer using EAP.
You need only to provide your engine specifications ?
Lance
This type of camshaft will have the greatest average HP/Torque.
The specify larger lobes to Crower Cams is common with MY 246/252 spec as used more often in Off Road racing.
I have the ability to "dyno" your engine in a computer using EAP.
You need only to provide your engine specifications ?
Lance
#87
Cammotion, thanks for the reply. I was thinking the same thing. I actually tried to contact you when I was ordering the cam but got in a hurry and didn’t follow up. I’ve got a T-56 close ratio, 3.70 in a 9” with a locker.
Lance, thanks for the offer but I’m still not convinced the 231/241 is big enough. The motor is assembled but not installed. I don’t mind changing the cam but I want to make the right decision.
Lance, thanks for the offer but I’m still not convinced the 231/241 is big enough. The motor is assembled but not installed. I don’t mind changing the cam but I want to make the right decision.
I have a couple cams I will suggest, but before I do, I want to talk a little bit about the bucking the comes with a high-overlap, rowdy idling camshaft. This is particularly of concern for enthusiasts that have manual transmissions.
Unlike automatics where an unlocked torque converter absorbs low RPM part throttle bucking, a manual transmission does not. What you will experience with a really rowdy camshaft in a stick shift car is, at low-RPM, part-throttle, the car will "buck" or jerk forward and back. This will happen on the highway if you try to cruise at too low of an RPM or in slow traffic or parking lots when you are trying to just slowly move along at a low RPM in gear.
A camshaft with a mild lope at idle might do this up to about 1200 RPM, a really rowdy camshaft might do this as high as 2200 RPM or more. So, you really have to be sure of how you use the vehicle and what characteristics are most important to you.
Some customer know this and don't care at all. They slip the clutch when they have to and have learned that they have to keep the RPMs up to avoid the bucking. Other customers get annoyed with any bucking at all and quickly start to hate their car after an aggressive camshaft is installed. Typically, the most likely person to complain is a customer with a late mode Corvette with a manual transmission. On the other extreme is the enthusiast who has had hotrods their whole life and are completely used to this type of thing and just consider it part of the experience.
This drivability aspect is something that each person must consider for themselves.
The camshaft that you have already has pretty low overlap (about 11 degrees). This camshaft will behave pretty well and probably wont buck much above 1200 RPM. So, in that aspect, some folks might be quite happy with it. Conversely, a bigger camshaft will sound a lot tougher, make more RPM and more power.
Here are a couple alternatives:
This is the Hot Street Stroker camshaft:
http://www.cammotion.com/camshafts/s...ectangle-port/
This camshaft has 17 degrees of overlap. It will have a great sounding idle, but keep bucking to about 1500-1600 RPM. It will make peak power about 6200 RPM and will like to be shifted between 6500-6700 RPM. It will have enough vacuum to run power brakes and such and drive pretty nice in a hotrod kind of way.
The Street King Stroker camshaft:
http://www.cammotion.com/camshafts/s...ectangle-port/
This camshaft is the quintessential street/strip cam. It has 26 degrees of overlap. It will want to idle at about 900 RPM, sound like the baddest car at the hang-out and have explosive acceleration from 4500-7000 RPM. IT will buck up to about 1800-2000 RPM at light part throttle. It should run power brakes if you have a really efficient power brake booster, but vacuum will be substantially reduced.
And, like always, if you want something in-between or different, we will make you a custom camshaft at no extra charge.
#89
Jake,
I'm running a 346 with 243 Lingenfelter ported heads, stock valve size, 90/90 wilson intake and tb 1 7/8 long tubes, cam is 242/248 608/612 110 LSA. 3600 stall 3;242 rear A4. I'm looking for a cam with explosive midrange could you recommend some numbers. Is this more of a top end power setup? Also need to keep the brakes working.
Thanks,
Michael.
I'm running a 346 with 243 Lingenfelter ported heads, stock valve size, 90/90 wilson intake and tb 1 7/8 long tubes, cam is 242/248 608/612 110 LSA. 3600 stall 3;242 rear A4. I'm looking for a cam with explosive midrange could you recommend some numbers. Is this more of a top end power setup? Also need to keep the brakes working.
Thanks,
Michael.
#91
Cam help
Looking for advice on a cam for a 1998 C5 Corvette automatic. The car has the following bolt-ons (AHR 1 3/4 inch headers with hi-flo cats &
x-pipe with Ti cat back exhaust, LS6 Intake Manifold, Callaway CAI, 3.42 gears with stock stall converter.)
I am sending out a set of 243 heads i got (LS6 w/sodium filled valves) from a 2003 Z06 to AI for there 226CC CNC package and should end up with about 11:1 compression.
I dont want to change the stock converter and this is a DD that will rarely if ever see a 1/4 mile. Just want a great street car that has more power than stock with just a touch of lope.
I have one cam recommendation (220 / 228) (578" / 578") 116 LSA+4
this would be ground on a cam motion 8620 core.
I am on the right track here?
Thanks
x-pipe with Ti cat back exhaust, LS6 Intake Manifold, Callaway CAI, 3.42 gears with stock stall converter.)
I am sending out a set of 243 heads i got (LS6 w/sodium filled valves) from a 2003 Z06 to AI for there 226CC CNC package and should end up with about 11:1 compression.
I dont want to change the stock converter and this is a DD that will rarely if ever see a 1/4 mile. Just want a great street car that has more power than stock with just a touch of lope.
I have one cam recommendation (220 / 228) (578" / 578") 116 LSA+4
this would be ground on a cam motion 8620 core.
I am on the right track here?
Thanks
#93
Looking for advice on a cam for a 1998 C5 Corvette automatic. The car has the following bolt-ons (AHR 1 3/4 inch headers with hi-flo cats &
x-pipe with Ti cat back exhaust, LS6 Intake Manifold, Callaway CAI, 3.42 gears with stock stall converter.)
I am sending out a set of 243 heads i got (LS6 w/sodium filled valves) from a 2003 Z06 to AI for there 226CC CNC package and should end up with about 11:1 compression.
I dont want to change the stock converter and this is a DD that will rarely if ever see a 1/4 mile. Just want a great street car that has more power than stock with just a touch of lope.
I have one cam recommendation (220 / 228) (578" / 578") 116 LSA+4
this would be ground on a cam motion 8620 core.
I am on the right track here?
Thanks
x-pipe with Ti cat back exhaust, LS6 Intake Manifold, Callaway CAI, 3.42 gears with stock stall converter.)
I am sending out a set of 243 heads i got (LS6 w/sodium filled valves) from a 2003 Z06 to AI for there 226CC CNC package and should end up with about 11:1 compression.
I dont want to change the stock converter and this is a DD that will rarely if ever see a 1/4 mile. Just want a great street car that has more power than stock with just a touch of lope.
I have one cam recommendation (220 / 228) (578" / 578") 116 LSA+4
this would be ground on a cam motion 8620 core.
I am on the right track here?
Thanks
It is a fine-line trying to get idle sound when using a stock torque converter. You could go as far as a 222/230 on 112+3. That will give a slight idle sound. If if were mine, I would probably bump the lift up to .595".
#97
Manual or automatic transmission?
Where do you plan to set the rev limiter?
That cam is surely good for something. Whether it's good for you is a different question.
Daily driver? Drag racing? Road course?
Are you OK with a narrow powerband?
Where do you plan to set the rev limiter?
That cam is surely good for something. Whether it's good for you is a different question.
Daily driver? Drag racing? Road course?
Are you OK with a narrow powerband?
#98
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That cam is more like a stroker cam that plans to rev and would want 12:1 compression minimum. In short, for your car, not a good cam.
#99
On The Tree
Currently is 7,200
Strip and street
#100
On The Tree
12.03cc
Tea stage 1 243
Cam with 1.8
1 7/8 with true dual
Ls6 intake tpis ported
And the usual bolt ons