summit 8711R1 cam for LM7 prep?
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summit 8711R1 cam for LM7 prep? https://www.summitracing.com/parts/SUM-8711R1
Just bought this. I liked the numbers and the advertised lobe profiles. I am new to the LS world, and I was surprised to find out Summit makes cams. Are there any issues with the blanks these are ground on? They say made in the USA?
What are yall's opinions and is there any prep work I should consider like chamfering the edges of the lobes?
It is a "stage 4" cam and is going into a mild 5.3 with long tube headers, truck intake, larger throttle body, injectors, etc. I'm using stock rockers, but has a HD trunion kit I guess you LS people call them? Its just a rocker shaft kit.
SPECS;
Just bought this. I liked the numbers and the advertised lobe profiles. I am new to the LS world, and I was surprised to find out Summit makes cams. Are there any issues with the blanks these are ground on? They say made in the USA?
What are yall's opinions and is there any prep work I should consider like chamfering the edges of the lobes?
It is a "stage 4" cam and is going into a mild 5.3 with long tube headers, truck intake, larger throttle body, injectors, etc. I'm using stock rockers, but has a HD trunion kit I guess you LS people call them? Its just a rocker shaft kit.
SPECS;
How are you planning to use the truck this 5.3 with a Stage 4 234/248 cam will go in? Have a aftermarket stall converter? Is this a race truck or daily, street-strip?
While that's a good cam for many applications, it has 13 degrees of overlap which massive for a mild 5.3 truck engine build. That Stage 4 cam will also hurt the bottom end torque at lower rpm in a 5.3 which is often important for how a truck is used. My personal take, not a cam I'd want in a daily driven 5.3 truck or a truck that does the typical truck stuff we use trucks for.
Summit's LS cam quality has a very good reputation from what I've read. My Summit 222/233 115 Ghost Cam looked great out of the box but went with something else.
While that's a good cam for many applications, it has 13 degrees of overlap which massive for a mild 5.3 truck engine build. That Stage 4 cam will also hurt the bottom end torque at lower rpm in a 5.3 which is often important for how a truck is used. My personal take, not a cam I'd want in a daily driven 5.3 truck or a truck that does the typical truck stuff we use trucks for.
Summit's LS cam quality has a very good reputation from what I've read. My Summit 222/233 115 Ghost Cam looked great out of the box but went with something else.
Last edited by 99 Black Bird T/A; Oct 6, 2022 at 09:09 AM.
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Teching In
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The honest truth is it will be a daily here soon. Its a street truck. Not using it for towing or hauling.
It's got the stupid TH350 in it. Probably some super low stall speed. But I'm working on building a 4l60e for it.
this cam be worth it? Ramps look a little rough. https://www.summitracing.com/parts/s...make/chevrolet
It's got the stupid TH350 in it. Probably some super low stall speed. But I'm working on building a 4l60e for it.
this cam be worth it? Ramps look a little rough. https://www.summitracing.com/parts/s...make/chevrolet
The honest truth is it will be a daily here soon. Its a street truck. Not using it for towing or hauling.
It's got the stupid TH350 in it. Probably some super low stall speed. But I'm working on building a 4l60e for it.
this cam be worth it? Ramps look a little rough. https://www.summitracing.com/parts/s...make/chevrolet
It's got the stupid TH350 in it. Probably some super low stall speed. But I'm working on building a 4l60e for it.
this cam be worth it? Ramps look a little rough. https://www.summitracing.com/parts/s...make/chevrolet
Agreed, the ramp rate of 49 is fast.
261@.006 -212 @ .050 = 49 intake is XER fast.
267@.006 -218 @ .050 = 49 exhaust is XER fast
However, the extra lift and lobe design should help avoid XER type issues (sewing noise, beat up valve train and appetite for fresh valve springs) and keep this lobe stable at high rpm from what I understand from Summit. They spintron test etc. Summit's claims, seem valid but I'd also use a very good quality valve spring.
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I think you will HATE that cam, unless your "truck" is VERY light like 3000 lbs or so, has LOTS of gear with normal sized tires like 4.56 with no more than 30" tires and more if the tires are larger, and has LOTS of converter like 3500 RPM or higher.
Doesn't seem like a wise choice at all.
I agree w 99 BlackBird, the 8728 is MUCH more appropriate for anything dimly resembling a DD street truck. Also as he said, those kinds of cams put a premium on valve spring performance, those need more attention than just "max lift". The ramp rates require high seat pressures so that the valves don't bounce off the seat when closing, and will suffer rapid wear-out if not up to the task.
Doesn't seem like a wise choice at all.
I agree w 99 BlackBird, the 8728 is MUCH more appropriate for anything dimly resembling a DD street truck. Also as he said, those kinds of cams put a premium on valve spring performance, those need more attention than just "max lift". The ramp rates require high seat pressures so that the valves don't bounce off the seat when closing, and will suffer rapid wear-out if not up to the task.
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I ended up getting this cam. Summit was awesome and changed my order. https://www.summitracing.com/parts/SUM-8715R1
Easier ramps. Will help me out in the long run as I'm not buying top of the line lifters. I will let yall know how she scoots!
Easier ramps. Will help me out in the long run as I'm not buying top of the line lifters. I will let yall know how she scoots!
