to degree or not to degree?
08-11-2012, 10:52 AM
#1
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to degree or not to degree? Like the title says. I bought a new cam for my single setup the icl is 106 and the lsa is 109+3 so should I degree or d2d? Since its +3.
Thanks
Dustin
Thanks
Dustin
08-11-2012, 11:25 AM
#2
Taken straight from Ed Curtis himself....
“I installed it dot to dot.”
This is one of the most popular comments I hear after less than ideal results are seen when a camshaft installation is completed. Just the mentioning of this sends chills down my spine.
The proper installation of a camshaft and its peripheral valvetrain is one of the most important jobs an installer must do when maximizing the performance of any engine combination. Any short cuts or miscues in this regard, and the overall success of the project, and its ultimate performance, will definitely suffer.
How can something so simple be so problematic?
Let’s start with the basic premise that everyone can have a bad day at work. Who’s to say the crankshaft keyway was machined absolutely “dead on” when the machinist set it up? I mean, even a slight error of a degree or two is no big deal considering the thousands and thousands of engines out in the world. They run, don't they? Maybe it wasn’t even a bad day but something that is machined off the mean number but still within manufacturing tolerances. What's a degree or two among friends?
Now we have the next piece of the tolerance puzzle, the timing set. There are a series of variables that can occur with this component. The relationship of the keyway to the crankshaft sprocket teeth, the location of the cam dowel hole to the cam sprocket teeth and then there’s always the possibility of “both” items being off. Why worry? Well, if each facet is off in the same direction, it is a cumulative error that will change the engine's dynamics. That's why verifying the intake centerline as it relates to top dead center is very important.
When you're installing these two pieces to the engine, who’s to say they are so perfect, there’s no reason to check them?
Nothing is further from the truth. You'll never hear a professional engine builder say this. At least not one that knows the hows and whys of valvetrain importance. This is the type of attention to detail that separates the engine assemblers from the engine builders.
No camshaft should be just installed “dot to dot” if the installer is a professional!
Now the novice or the weekend mechanic might be able to justify doing a camshaft installation in this manner just because the tools required are not something a newbie has put the investment in. It's "almost" forgivable when this is spoken. However, when I hear his “dot to dot” comment from a shop that just charged a customer a lot of money to do the install, well, it definitely crosses the line and takes them off the referral list.
Take your time and verify everything. If you don't have the time, tools or talent to do it yourself, find a professional to do it for you. It's worth the effort!
“I installed it dot to dot.”
This is one of the most popular comments I hear after less than ideal results are seen when a camshaft installation is completed. Just the mentioning of this sends chills down my spine.
The proper installation of a camshaft and its peripheral valvetrain is one of the most important jobs an installer must do when maximizing the performance of any engine combination. Any short cuts or miscues in this regard, and the overall success of the project, and its ultimate performance, will definitely suffer.
How can something so simple be so problematic?
Let’s start with the basic premise that everyone can have a bad day at work. Who’s to say the crankshaft keyway was machined absolutely “dead on” when the machinist set it up? I mean, even a slight error of a degree or two is no big deal considering the thousands and thousands of engines out in the world. They run, don't they? Maybe it wasn’t even a bad day but something that is machined off the mean number but still within manufacturing tolerances. What's a degree or two among friends?
Now we have the next piece of the tolerance puzzle, the timing set. There are a series of variables that can occur with this component. The relationship of the keyway to the crankshaft sprocket teeth, the location of the cam dowel hole to the cam sprocket teeth and then there’s always the possibility of “both” items being off. Why worry? Well, if each facet is off in the same direction, it is a cumulative error that will change the engine's dynamics. That's why verifying the intake centerline as it relates to top dead center is very important.
When you're installing these two pieces to the engine, who’s to say they are so perfect, there’s no reason to check them?
Nothing is further from the truth. You'll never hear a professional engine builder say this. At least not one that knows the hows and whys of valvetrain importance. This is the type of attention to detail that separates the engine assemblers from the engine builders.
No camshaft should be just installed “dot to dot” if the installer is a professional!
Now the novice or the weekend mechanic might be able to justify doing a camshaft installation in this manner just because the tools required are not something a newbie has put the investment in. It's "almost" forgivable when this is spoken. However, when I hear his “dot to dot” comment from a shop that just charged a customer a lot of money to do the install, well, it definitely crosses the line and takes them off the referral list.
Take your time and verify everything. If you don't have the time, tools or talent to do it yourself, find a professional to do it for you. It's worth the effort!
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08-12-2012, 04:17 AM
#8
http://www.compcams.com/Technical/In.../Files/145.pdf
08-12-2012, 02:55 PM
#10
unfortunately, theres no off the shelf comp kit for motor in car and LS heads already on and torqued down...
which means you have do do a custom kit like I did
I bascially bought the in car BBC kit, and I bought a longer rod for the dial gauge...and welded part of an old pushrod on the end
then I bought an adapter to use the kit on the rocker bolt holes instead of the head bolt holes
and I measure from the lifter, you cannot measure from the rocker itself as the valve spring spring pressure will collapse the llifter and distort your readings
it takes a little work to get it set up as there are a bunch of pieces to it, but it works and it works as reliably just as the kit that uses the head bolt holes with the heads off the engine.
08-12-2012, 03:08 PM
#11
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This is true - you should degree the cam. It's best practice and you will #1 insure that you are getting the optimal results from your setup and #2 have piece of mind that your cam is working as intended. If I were to bring it to a professional shop - I would undoubtedly expect that professionally degree my cam.
With that being said - MANY, many people install cams dot-to-dot.... including me. It may not be the best way to do things, but it works fine almost everytime. I installed a cam in my Vette using the "dot to dot" method and she's has seen her fair share of abuse for the past 8k miles with zero issues.
If you have the time and tools - degree your cam. But if you decide not and only want to do the dot-to-dot method, I wouldn't even worry about it. Good Luck.
With that being said - MANY, many people install cams dot-to-dot.... including me. It may not be the best way to do things, but it works fine almost everytime. I installed a cam in my Vette using the "dot to dot" method and she's has seen her fair share of abuse for the past 8k miles with zero issues.
If you have the time and tools - degree your cam. But if you decide not and only want to do the dot-to-dot method, I wouldn't even worry about it. Good Luck.
08-12-2012, 03:43 PM
#14
Weird. Says right on the item description it's for heads on. There's one on the way to my house as we speak......
COMP Cams® Camshaft Degree Kit for GM Gen III/IV LS Engines
The Camshaft Degree Kit for GM Gen III/IV LS Engines from COMP Cams® contains all the tools and fixtures necessary to precisely set camshaft timing in order to make up for engine machining tolerances. Degreeing positions the camshaft to get the best performance out of your engine, so that you can get the most horsepower and torque possible from your application.
This degree kit ships with everything required to degree a camshaft when the cylinder heads are either on or off the engine, including a 9" degree wheel, wire degree wheel pointer, heads off cam checking fixture, 0-1" travel dial indicator, 5" dial indicator extension, LS-specific threaded stands, LS-type crankshaft socket, plate-style top dead center (TDC) stop and instructions. Your investment is kept safe and secure in the included foam-padded carrying case.
Features & Benefits:
• Kit has all the tools necessary to degree LS camshafts in one convenient package
• Degreeing gets more horsepower & torque out of your engine
• Works with heads installed or on base short blocks with no heads installed
• Kit includes: 9" degree wheel, wire degree wheel pointer, heads off cam checking fixture, 0-1": dial indicator, 5" dial indicator extension, LS-specific threaded stands & crankshaft socket, & -style TDC stop
• Case with soft foam padding protects kit
COMP Cams® Camshaft Degree Kit for GM Gen III/IV LS Engines
The Camshaft Degree Kit for GM Gen III/IV LS Engines from COMP Cams® contains all the tools and fixtures necessary to precisely set camshaft timing in order to make up for engine machining tolerances. Degreeing positions the camshaft to get the best performance out of your engine, so that you can get the most horsepower and torque possible from your application.
This degree kit ships with everything required to degree a camshaft when the cylinder heads are either on or off the engine, including a 9" degree wheel, wire degree wheel pointer, heads off cam checking fixture, 0-1" travel dial indicator, 5" dial indicator extension, LS-specific threaded stands, LS-type crankshaft socket, plate-style top dead center (TDC) stop and instructions. Your investment is kept safe and secure in the included foam-padded carrying case.
Features & Benefits:
• Kit has all the tools necessary to degree LS camshafts in one convenient package
• Degreeing gets more horsepower & torque out of your engine
• Works with heads installed or on base short blocks with no heads installed
• Kit includes: 9" degree wheel, wire degree wheel pointer, heads off cam checking fixture, 0-1": dial indicator, 5" dial indicator extension, LS-specific threaded stands & crankshaft socket, & -style TDC stop
• Case with soft foam padding protects kit
08-12-2012, 03:48 PM
#15
well definitely let me know..
it used to be for heads off only...
and in the pictures I can find of the kit, it does not look like it has any way to do it with the heads on
maybe they finally listed to all the LS guys bitching about a degree kit for in the car with the heads on
did you remember to buy the Piston Stop part # 4795
cause you will need one to do it with the heads on...its not in that kit
it used to be for heads off only...
and in the pictures I can find of the kit, it does not look like it has any way to do it with the heads on
maybe they finally listed to all the LS guys bitching about a degree kit for in the car with the heads on
did you remember to buy the Piston Stop part # 4795
cause you will need one to do it with the heads on...its not in that kit
08-12-2012, 03:52 PM
#16
True true! I read a good write up here http://www.gmhightechperformance.com...m/viewall.html
There's a few things I'll have to make, but it should be pretty easy.
I wasn't arguing with you Scott, just checking to see I didn't get screwed!
There's a few things I'll have to make, but it should be pretty easy.
I wasn't arguing with you Scott, just checking to see I didn't get screwed!
08-12-2012, 04:04 PM
#17
even that write up says its not designed for the LS1 heads....have to make a custom piece to be able to use another hole...
which is what I did...
I wasnt saying you were arguing.... I figured you just googled and found something that said ls1 heads on kit...
you definitively didnt get screwed by buying it... you just need to buy a piston stop, and you need to fabricate something...
I took the longer gauge rod and just addeded the pushrod rounded end to it so it would always sit properly in the cup of the lifter...which is a much better idea than trying to get the little tip on the lifter and hoping its centered and doesnt move on you.
you can buy a thread pitch adapter to go from the SBC to an LS head rocker bolt, which will give you better positioning and a more solid mount for the dial gauge...and will make it a really easy universal kit at that point
If I wasnt out on the road right now, I would break mine out and take some pictures...
I'll be using it in a few weeks when I get home from this tour when I plan to drop all my stuff into a mustang and I'll be doing a cam change to a pretty big cam (252/274)
which is what I did...
I wasnt saying you were arguing.... I figured you just googled and found something that said ls1 heads on kit...
you definitively didnt get screwed by buying it... you just need to buy a piston stop, and you need to fabricate something...
I took the longer gauge rod and just addeded the pushrod rounded end to it so it would always sit properly in the cup of the lifter...which is a much better idea than trying to get the little tip on the lifter and hoping its centered and doesnt move on you.
you can buy a thread pitch adapter to go from the SBC to an LS head rocker bolt, which will give you better positioning and a more solid mount for the dial gauge...and will make it a really easy universal kit at that point
If I wasnt out on the road right now, I would break mine out and take some pictures...
I'll be using it in a few weeks when I get home from this tour when I plan to drop all my stuff into a mustang and I'll be doing a cam change to a pretty big cam (252/274)
08-12-2012, 04:27 PM
#18
True true! I read a good write up here http://www.gmhightechperformance.com...m/viewall.html
There's a few things I'll have to make, but it should be pretty easy.
I wasn't arguing with you Scott, just checking to see I didn't get screwed!
There's a few things I'll have to make, but it should be pretty easy.
I wasn't arguing with you Scott, just checking to see I didn't get screwed!
08-12-2012, 06:31 PM
#19
I degree'd my cam. Came out within spec...Peace of mind at most...I felt like I wasted the $200 on the kit (which sucked BTW).
I would assume MOST of the time you will be fine dot to dot, but that one time its off could destory an engine. Its just one of those things you are suppose to do, but can get away with not doing it.
I would assume MOST of the time you will be fine dot to dot, but that one time its off could destory an engine. Its just one of those things you are suppose to do, but can get away with not doing it.
