Judge my planned engine build
11-17-2017, 07:08 PM
#23
When people refer to the Hot Rod GM cam test; everyone seems to mis-remember(LOL forget) that the 01 LS6/LS2 cam had horrendous valvetrain issues even with the Comp 918 springs. Which are better than the GM blue ****. GM cams have goofy lobes. I know this because several companies offer same lift. Same @.050" cams that offer way more stability and horsepower after six grand in GM crate motor stock cars/modifieds. Etc.
I would not mill these 799s
Run the GM .051" gaskets and as plenty of others have stated. Stay in that 200-210@.050" duration range and this build will be a success.
The LS6 cam worked fantastic in a 3080 pound coupe with a 3.42 rear and an M12 trans which had an even more giddy up 2.97 first gear than my 2.66 M6 in my car
IT IS NOT A TOWING CAM
I would not mill these 799s
Run the GM .051" gaskets and as plenty of others have stated. Stay in that 200-210@.050" duration range and this build will be a success.
The LS6 cam worked fantastic in a 3080 pound coupe with a 3.42 rear and an M12 trans which had an even more giddy up 2.97 first gear than my 2.66 M6 in my car
IT IS NOT A TOWING CAM
11-17-2017, 07:21 PM
#24
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Originally Posted by A.R. Shale Targa
When people refer to the Hot Rod GM cam test; everyone seems to mis-remember(LOL forget) that the 01 LS6/LS2 cam had horrendous valvetrain issues even with the Comp 918 springs. Which are better than the GM blue ****. GM cams have goofy lobes. I know this because several companies offer same lift. Same @.050" cams that offer way more stability and horsepower after six grand in GM crate motor stock cars/modifieds. Etc.
I would not mill these 799s
Run the GM .051" gaskets and as plenty of others have stated. Stay in that 200-210@.050" duration range and this build will be a success.
The LS6 cam worked fantastic in a 3080 pound coupe with a 3.42 rear and an M12 trans which had an even more giddy up 2.97 first gear than my 2.66 M6 in my car
IT IS NOT A TOWING CAM
I would not mill these 799s
Run the GM .051" gaskets and as plenty of others have stated. Stay in that 200-210@.050" duration range and this build will be a success.
The LS6 cam worked fantastic in a 3080 pound coupe with a 3.42 rear and an M12 trans which had an even more giddy up 2.97 first gear than my 2.66 M6 in my car
IT IS NOT A TOWING CAM
I put a ls6 cam in a 5.3 and hated it. No low end.
Also, for a motor that is going to see towing duty, lower compression might be better because your g/cylinder is going to be high at low rpm. So again, like AR said. Just install the 799, HG, and run.
I still stand by recommending cam motion 5.3 S2 drop in cam. If you are that worried about the springs do psi 1511. Try to find a breakage report on them.
11-18-2017, 06:26 AM
#25
When people refer to the Hot Rod GM cam test; everyone seems to mis-remember(LOL forget) that the 01 LS6/LS2 cam had horrendous valvetrain issues even with the Comp 918 springs. Which are better than the GM blue ****. GM cams have goofy lobes. I know this because several companies offer same lift. Same @.050" cams that offer way more stability and horsepower after six grand in GM crate motor stock cars/modifieds. Etc.
I would not mill these 799s
Run the GM .051" gaskets and as plenty of others have stated. Stay in that 200-210@.050" duration range and this build will be a success.
The LS6 cam worked fantastic in a 3080 pound coupe with a 3.42 rear and an M12 trans which had an even more giddy up 2.97 first gear than my 2.66 M6 in my car
IT IS NOT A TOWING CAM
I would not mill these 799s
Run the GM .051" gaskets and as plenty of others have stated. Stay in that 200-210@.050" duration range and this build will be a success.
The LS6 cam worked fantastic in a 3080 pound coupe with a 3.42 rear and an M12 trans which had an even more giddy up 2.97 first gear than my 2.66 M6 in my car
IT IS NOT A TOWING CAM
THANK YOU!!! Ls2 cam valve floated on that test and that always gets lost!!!
I put a ls6 cam in a 5.3 and hated it. No low end.
Also, for a motor that is going to see towing duty, lower compression might be better because your g/cylinder is going to be high at low rpm. So again, like AR said. Just install the 799, HG, and run.
I still stand by recommending cam motion 5.3 S2 drop in cam. If you are that worried about the springs do psi 1511. Try to find a breakage report on them.
I put a ls6 cam in a 5.3 and hated it. No low end.
Also, for a motor that is going to see towing duty, lower compression might be better because your g/cylinder is going to be high at low rpm. So again, like AR said. Just install the 799, HG, and run.
I still stand by recommending cam motion 5.3 S2 drop in cam. If you are that worried about the springs do psi 1511. Try to find a breakage report on them.
And I did notice the float issue on the cam test. Not an issue for me I will set my Rev limiter at 6k and it will probably never see that high anyway.
11-18-2017, 07:03 AM
#26
ModSquad
iTrader: (6)
Guessing it’s going in the Landcruiser in your sig. Obviously you’ve been in the rear end since it’s got a locker...what gear you running currently?
11-18-2017, 07:39 AM
#27
Haven't touched the rear, factory elocker, 4.11, 9.5" Which is part of the swap justification. With that rear, 35s, and a standard 4l60 (built of course) it will make it the equivalent of somewhere between the standard 3.42 and the HD 3.73 Silverado setup.
11-18-2017, 07:06 PM
#28
The higher lift will produce more power. The only downside to the high lift version is the extra $99 for the valve springs. .550" lift is a nice lift for a camshaft of that duration. It makes for a very nice, smooth lobe that lends itself to great longevity and reliability if you put a good amount of miles on your truck.
11-18-2017, 11:11 PM
#29
TECH Senior Member
So .600 lift is nice, but not the setup for longevity. No wonder your lobes don't even go that high for the lower durations
11-19-2017, 06:09 AM
#30
The higher lift will produce more power. The only downside to the high lift version is the extra $99 for the valve springs. .550" lift is a nice lift for a camshaft of that duration. It makes for a very nice, smooth lobe that lends itself to great longevity and reliability if you put a good amount of miles on your truck.
11-19-2017, 01:34 PM
#31
How much lift does a stock ls7 use?
Of course its with 1.8 rockers but still, youre looking for spring longevity vs lift its close to .600.
Im sure there are plenty running well over .600 with beehives or duals that have never checked nor changed anything in well over 100k miles.
The spring quality like PAC or Manley or PSI or a few others like that will give you longevity mile after mile. Just because it is under .600 doesnt mean its not aggressive either.
The lower (sub 210) durations, yes they would normally use a lower lift because you can get overly aggressive there if using a 1.7 rocker looking for .600 lift, but even then it can be done without making a noisy valvetrain and wearing down springs.
11-19-2017, 04:31 PM
#32
TECH Senior Member
Sounds good. Thank you!
Looking thru Cam Motion's lobe list, many of the lobes in the 210-220 max duration range don't go as high as .600 w/1.7 rockers, which tells me that they consider .600 a bit much at the lower durations.
Looking thru Cam Motion's lobe list, many of the lobes in the 210-220 max duration range don't go as high as .600 w/1.7 rockers, which tells me that they consider .600 a bit much at the lower durations.
Last edited by G Atsma; 11-19-2017 at 04:40 PM.
11-19-2017, 07:26 PM
#33
Id have to say that is not correct.
How much lift does a stock ls7 use?
Of course its with 1.8 rockers but still, youre looking for spring longevity vs lift its close to .600.
Im sure there are plenty running well over .600 with beehives or duals that have never checked nor changed anything in well over 100k miles.
The spring quality like PAC or Manley or PSI or a few others like that will give you longevity mile after mile. Just because it is under .600 doesnt mean its not aggressive either.
The lower (sub 210) durations, yes they would normally use a lower lift because you can get overly aggressive there if using a 1.7 rocker looking for .600 lift, but even then it can be done without making a noisy valvetrain and wearing down springs.
How much lift does a stock ls7 use?
Of course its with 1.8 rockers but still, youre looking for spring longevity vs lift its close to .600.
Im sure there are plenty running well over .600 with beehives or duals that have never checked nor changed anything in well over 100k miles.
The spring quality like PAC or Manley or PSI or a few others like that will give you longevity mile after mile. Just because it is under .600 doesnt mean its not aggressive either.
The lower (sub 210) durations, yes they would normally use a lower lift because you can get overly aggressive there if using a 1.7 rocker looking for .600 lift, but even then it can be done without making a noisy valvetrain and wearing down springs.
-It isn't so much spring strength/rate/spring quality that is the problem (as you said, the aftermarket options we love are reliable)
The real problem I see when high lift is in play is with the valve hardware (guide/hardware), and lifter. Most predictably the lifter, since it is often the most critical/moving and overlooked/undervalued part. They are seldom fully recognized in their potential (how much 'spring' or 'abuse' can a given lifter support? I have yet to see a chart for comparing this quality)
Ex. controlling the motion might be easy with enough spring strength, but the hardware used to secure the guide takes additional beating because of that strength.
I feel we are more likely to suffer lifter failure/collapse, and valve guide/wear in associated head components around the valve, and if there is any mis-geometry the resulting increase in wear will be further compounded by the strength of the spring. This is why I avoid the strongest spring with the highest lift, not because I am worried about breaking the spring (which may still be a concern...) but because I am worried about the valve-job (guide is made of soft metal usually) straightness, that essential seal, and the delicate, intricate device known as a roller-lifter containing any number of roller-pellets (a joke about the roaming roller-pellets you found in the oil pan that time...) , of which if one is lost, the whole engine comes crashing down around it.... and may be rendered non-reusable.
11-20-2017, 01:33 PM
#34
11-20-2017, 05:44 PM
#36
Those two are pretty close from a valve event perspective. Once in the vehicle, it would probably be tough to tell them apart.
11-21-2017, 09:15 AM
#39
They are so close, I doubt you can tell the difference once installed, but the Stage 1 6 liter camshaft was created for what you are doing. So, that is the one that I would choose.
11-21-2017, 10:01 AM
#40
Alright so I ordered the cam motion 6.0 s1 high lift cam and springs. I will post up when the engine is built and dyno's for others that are curious. Thanks to everyone that posted.
Here is my final build plan:
5.7 LS1 block and rotating assembly (and cam above)
stock 799 heads
truck intake, injectors, ported stock TB
CAI, long tubes, duals
I hope to make a nice flat torque curve between 350 and 400 at the wheels with about the same HP maybe slightly less
Here is my final build plan:
5.7 LS1 block and rotating assembly (and cam above)
stock 799 heads
truck intake, injectors, ported stock TB
CAI, long tubes, duals
I hope to make a nice flat torque curve between 350 and 400 at the wheels with about the same HP maybe slightly less