Cam lift question, yes I read the stickys.
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Staging Lane
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Cam lift question, yes I read the stickys.
I ordered a comp cam and they sent me a 224/224 .581/.581 112lsa ---- They got everything right but the lift. I needed a .550/.550 due to the fact I have 1.8 rockers so the end result was suppose to be a .581/.581. Im in the middle of a turbo set-up and was wondering what the effect of my lift being 615/.615 now with the 1.8 rockers... Would I have clearance issues, driveability issues or would this be ok? I have 317 heads on a stock ls1 block and springs that can handle .650 lift. Thanks for any help in advance.
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If you are stock heads, gaskets, and pistons, you will be fine. Maximum lift is NOT the determining factor when checking P to V. Duration and acceleration on and off the seat are the determining factors. The only issue you will probably have is valve float depending on what lobe family you are using, how much boost the back of the valves will see and which rockers you are using. Those sound like XE-R lobes which will be fairly hard to control with the 1.8 ratio especially when you add the boost to the equation. At this point it all depends on what kind of RPM you are shooting for.
Shane
Shane
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Staging Lane
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If you are stock heads, gaskets, and pistons, you will be fine. Maximum lift is NOT the determining factor when checking P to V. Duration and acceleration on and off the seat are the determining factors. The only issue you will probably have is valve float depending on what lobe family you are using, how much boost the back of the valves will see and which rockers you are using. Those sound like XE-R lobes which will be fairly hard to control with the 1.8 ratio especially when you add the boost to the equation. At this point it all depends on what kind of RPM you are shooting for.
Shane
Shane
#4
TECH Senior Member
Shane is correct, I agree with him.
.581 lift is XE-R, lobe 3722
.534 lift is XE low lift,lobe 3753
.568 lift is xe high lift,lobe 3715
With those lifts and XE-R ramp rate I do not recomment 1.8 rockers (especialy in boost situation). Ramp rate is too harsh to do that and valvetrain instability is imminent.
Either change cam or rockers, personaly I say rockers.
.581 lift is XE-R, lobe 3722
.534 lift is XE low lift,lobe 3753
.568 lift is xe high lift,lobe 3715
With those lifts and XE-R ramp rate I do not recomment 1.8 rockers (especialy in boost situation). Ramp rate is too harsh to do that and valvetrain instability is imminent.
Either change cam or rockers, personaly I say rockers.
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Staging Lane
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Shane is correct, I agree with him.
.581 lift is XE-R, lobe 3722
.534 lift is XE low lift,lobe 3753
.568 lift is xe high lift,lobe 3715
With those lifts and XE-R ramp rate I do not recomment 1.8 rockers (especialy in boost situation). Ramp rate is too harsh to do that and valvetrain instability is imminent.
Either change cam or rockers, personaly I say rockers.
.581 lift is XE-R, lobe 3722
.534 lift is XE low lift,lobe 3753
.568 lift is xe high lift,lobe 3715
With those lifts and XE-R ramp rate I do not recomment 1.8 rockers (especialy in boost situation). Ramp rate is too harsh to do that and valvetrain instability is imminent.
Either change cam or rockers, personaly I say rockers.
#6
TECH Senior Member
Do you have a cam card? Can you post a pic of it!
I think that by now we understand that you ordered a 224 cam on .550 lift.
We are telling you that .581 lift is XE-R lobes (very agressive). They do not work with 1.8 rockers
I posted above the lobe numbers for XE.
THERE IS NO XE LOBES WITH .050 lift, it is either .568 or .534
Seing that you are boosted, with 1.8 rockers, I would use the .534 lift.
THAT IS LOBE # 3753 (Both intake and exhaust).
Please do not ask what it will do for your performance again.
.581 lioft XE-R DO NOT WORK WITH 1.8 ROCKERS IN BOOST SITUATIONS>
IS THAT CLEAR.
(Sorry I think I just lost my )
I think that by now we understand that you ordered a 224 cam on .550 lift.
We are telling you that .581 lift is XE-R lobes (very agressive). They do not work with 1.8 rockers
I posted above the lobe numbers for XE.
THERE IS NO XE LOBES WITH .050 lift, it is either .568 or .534
Seing that you are boosted, with 1.8 rockers, I would use the .534 lift.
THAT IS LOBE # 3753 (Both intake and exhaust).
Please do not ask what it will do for your performance again.
.581 lioft XE-R DO NOT WORK WITH 1.8 ROCKERS IN BOOST SITUATIONS>
IS THAT CLEAR.
(Sorry I think I just lost my )
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Staging Lane
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Do you have a cam card? Can you post a pic of it!
I think that by now we understand that you ordered a 224 cam on .550 lift.
We are telling you that .581 lift is XE-R lobes (very agressive). They do not work with 1.8 rockers
I posted above the lobe numbers for XE.
THERE IS NO XE LOBES WITH .050 lift, it is either .568 or .534
Seing that you are boosted, with 1.8 rockers, I would use the .534 lift.
THAT IS LOBE # 3753 (Both intake and exhaust).
Please do not ask what it will do for your performance again.
.581 lift XE-R DO NOT WORK WITH 1.8 ROCKERS IN BOOST SITUATIONS>
IS THAT CLEAR.
(Sorry I think I just lost my )
I think that by now we understand that you ordered a 224 cam on .550 lift.
We are telling you that .581 lift is XE-R lobes (very agressive). They do not work with 1.8 rockers
I posted above the lobe numbers for XE.
THERE IS NO XE LOBES WITH .050 lift, it is either .568 or .534
Seing that you are boosted, with 1.8 rockers, I would use the .534 lift.
THAT IS LOBE # 3753 (Both intake and exhaust).
Please do not ask what it will do for your performance again.
.581 lift XE-R DO NOT WORK WITH 1.8 ROCKERS IN BOOST SITUATIONS>
IS THAT CLEAR.
(Sorry I think I just lost my )