lifter selection
04-04-2015 | 12:59 PM
#1
Thread Starter
Teching In
Joined: Dec 2013
Posts: 30
Likes: 0
lifter selection Well after a complete engine build I decided to reuse my old ls7 lifters, and now they are starting to worry me so I'm looking to upgrade...I'm not looking to spend $700 on lifters but I want a quality part that I don't need to worry about, what would you guys recommend for my setup?
Ls7
Caddy
Comp pro magnums
Comp drop ins
Morel drop ins
Morel street link bar
Etc?
Setup is a forged 12:1 347, 239/250 .624/.615 114+4, tea stage 2 799s with their upgrade pac spring set, 4150/super vic, and about 7500rpm on a 250-400 shot through a puck and speedtech softline fogger
Thanks jn advance
Ls7
Caddy
Comp pro magnums
Comp drop ins
Morel drop ins
Morel street link bar
Etc?
Setup is a forged 12:1 347, 239/250 .624/.615 114+4, tea stage 2 799s with their upgrade pac spring set, 4150/super vic, and about 7500rpm on a 250-400 shot through a puck and speedtech softline fogger
Thanks jn advance
04-04-2015 | 01:46 PM
#2
TECH Veteran
Joined: Sep 2014
Posts: 4,814
Likes: 614
From: Mississippi
I wouldn't do a drop in lifter if you plan on revving past 7K all the time.....
I would personally do morel 5206 lifters if your budget allows. You really can't beat a link bar setup as far as stability and reliability.
Best drop in that's under 200 bucks I have seen/heard is morel 5315 lifters.
I would personally do morel 5206 lifters if your budget allows. You really can't beat a link bar setup as far as stability and reliability.
Best drop in that's under 200 bucks I have seen/heard is morel 5315 lifters.
04-04-2015 | 11:34 PM
#5
If you want to spin the motor above 7k then you need a high quality lifter. Have some spun the motor over 7k with stock style drop in lifters, yes...but that does not mean it's the right thing to do. Personally if I am building a high rpm motor, Johnson short travel lifters would be on my short list.
04-05-2015 | 01:30 AM
#6
TECH Veteran
Joined: Sep 2014
Posts: 4,814
Likes: 614
From: Mississippi
Soon I plan on running 10s all motor with my 6 speed and driving the car EVERYWHERE..... I wouldn't dare to that with a drop in lifter. I hate to see you have a great combo and skimp out on lifters..... After all I know you don't want your lobes on that cam ate for dinner by a cheap roller and cause disaster. Just keeping it real.
04-05-2015 | 06:46 PM
#7
Thread Starter
Teching In
Joined: Dec 2013
Posts: 30
Likes: 0
I understand what you guys are saying, but if I took the most expensive and insured route in everything with this car id be in the poor house...If the btr slr lifters were still available I'd be running those, multiple cars in my area running bottom 5s in the 1/8 with them...If honestly just torn between caddy lifters, morel drop ins, or the street link bars right now
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04-07-2015 | 01:18 AM
#9
At 7000 rpm the camshaft moves at 3500 rpm. That is 58 revolutions per second. So in that small window of time you are operating 1 lifter at lets say 280* of the total 360* it travels (280 adv duration). So for roughly 3/4 of an entire revolution you are making the lifter work. It works against spring pressure, cylinder pressure, NITROUS, and oil pressure as well as staying on the lobe face itself. So basically for 58 revolutions per second that lifter is working at 75% capacity(per unit of time) or more. It is intaking oil, using it to supply pressure to the lifter internals, and bleeding it back off. 58 times in 1 second this happens. All the while it is fighting those other issues that are trying to force the oil out of it or compress it inside of it, or not even fill it entirely.
Using that overly simplified example you can see the need for high quality components to work at that high rate of speed. The window to bleed off all of that oil pressure to not cause pump up becomes VERY small above 6k and even more so at 7k.
That doesnt even take into effect the oil viscosity you are using. Most of the short travel lifters recommend 5-30 AT MOST.
We have the 5206 tie bars at a very good gp price or the 4708 non tie bar drop ins as well.
Now maybe you can rationalize buying expensive lifters for your 7k build. Ls7 lifters at 7k with the honest spring pressure it would takr to control the valves that high wouldnt last. And the "caddy high rev" lifters have not shown to be the most reliable.
On the other hand, a solid roller lifter would give you what you want unless you dont want to check your valvetrain every so often and set valve lash. They are not super expensive either and can be ran on a roller lobe. But you may want to ditch the high volume oil pump if you are using one.
http://www.coloradospeed.com/morel-mechanical-roller-lifters-ls-842d-tb-mech-roller-for-std-hi-lift-p-32271.html
The other big question is will you step up to 11/32 or 3/8 pushrods? I doubt the 5/16 will hold that. And depending on the pac spring, they may not either.
Using that overly simplified example you can see the need for high quality components to work at that high rate of speed. The window to bleed off all of that oil pressure to not cause pump up becomes VERY small above 6k and even more so at 7k.
That doesnt even take into effect the oil viscosity you are using. Most of the short travel lifters recommend 5-30 AT MOST.
We have the 5206 tie bars at a very good gp price or the 4708 non tie bar drop ins as well.
Now maybe you can rationalize buying expensive lifters for your 7k build. Ls7 lifters at 7k with the honest spring pressure it would takr to control the valves that high wouldnt last. And the "caddy high rev" lifters have not shown to be the most reliable.
On the other hand, a solid roller lifter would give you what you want unless you dont want to check your valvetrain every so often and set valve lash. They are not super expensive either and can be ran on a roller lobe. But you may want to ditch the high volume oil pump if you are using one.
http://www.coloradospeed.com/morel-mechanical-roller-lifters-ls-842d-tb-mech-roller-for-std-hi-lift-p-32271.html
The other big question is will you step up to 11/32 or 3/8 pushrods? I doubt the 5/16 will hold that. And depending on the pac spring, they may not either.
Last edited by COSPEED2; 04-07-2015 at 01:29 AM.
04-09-2015 | 08:09 PM
#10
At 7000 rpm the camshaft moves at 3500 rpm. That is 58 revolutions per second. So in that small window of time you are operating 1 lifter at lets say 280* of the total 360* it travels (280 adv duration). So for roughly 3/4 of an entire revolution you are making the lifter work. It works against spring pressure, cylinder pressure, NITROUS, and oil pressure as well as staying on the lobe face itself. So basically for 58 revolutions per second that lifter is working at 75% capacity(per unit of time) or more. It is intaking oil, using it to supply pressure to the lifter internals, and bleeding it back off. 58 times in 1 second this happens. All the while it is fighting those other issues that are trying to force the oil out of it or compress it inside of it, or not even fill it entirely.
Using that overly simplified example you can see the need for high quality components to work at that high rate of speed. The window to bleed off all of that oil pressure to not cause pump up becomes VERY small above 6k and even more so at 7k.
That doesnt even take into effect the oil viscosity you are using. Most of the short travel lifters recommend 5-30 AT MOST.
We have the 5206 tie bars at a very good gp price or the 4708 non tie bar drop ins as well.
Now maybe you can rationalize buying expensive lifters for your 7k build. Ls7 lifters at 7k with the honest spring pressure it would takr to control the valves that high wouldnt last. And the "caddy high rev" lifters have not shown to be the most reliable.
On the other hand, a solid roller lifter would give you what you want unless you dont want to check your valvetrain every so often and set valve lash. They are not super expensive either and can be ran on a roller lobe. But you may want to ditch the high volume oil pump if you are using one.
http://www.coloradospeed.com/morel-m...t-p-32271.html
The other big question is will you step up to 11/32 or 3/8 pushrods? I doubt the 5/16 will hold that. And depending on the pac spring, they may not either.
Using that overly simplified example you can see the need for high quality components to work at that high rate of speed. The window to bleed off all of that oil pressure to not cause pump up becomes VERY small above 6k and even more so at 7k.
That doesnt even take into effect the oil viscosity you are using. Most of the short travel lifters recommend 5-30 AT MOST.
We have the 5206 tie bars at a very good gp price or the 4708 non tie bar drop ins as well.
Now maybe you can rationalize buying expensive lifters for your 7k build. Ls7 lifters at 7k with the honest spring pressure it would takr to control the valves that high wouldnt last. And the "caddy high rev" lifters have not shown to be the most reliable.
On the other hand, a solid roller lifter would give you what you want unless you dont want to check your valvetrain every so often and set valve lash. They are not super expensive either and can be ran on a roller lobe. But you may want to ditch the high volume oil pump if you are using one.
http://www.coloradospeed.com/morel-m...t-p-32271.html
The other big question is will you step up to 11/32 or 3/8 pushrods? I doubt the 5/16 will hold that. And depending on the pac spring, they may not either.