Cam Install Questions 02' 5.3l

Ok have a few questions about installing a comp cam in my 02 silverado 5.3l- Cam is the Comp XR265HR- Motor has 82K miles.

1. Will I need a new timing set from Comp so I can degree the cam?
2. Is it even necassary to degree the cam? Will stock timing gears/chain work?
3. Will comp 918's work with stock retainers? If not is there any significant difference between Comps steel retainers vs there titanium besides weight?
4. Oil pump- Should I replace? Still has 45psi at idle warm and over 60psi while driving.
5. Lifters? Stock ones ok or should I go LS7?
6. Other than pushrods anything else I should address while Im in there?
Any thoughts will be greatly appreciatted, Thanks-

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Originally Posted by LS6 Silverado

Ok have a few questions about installing a comp cam in my 02 silverado 5.3l- Cam is the Comp XR265HR- Motor has 82K miles.

1. Will I need a new timing set from Comp so I can degree the cam?
2. Is it even necassary to degree the cam? Will stock timing gears/chain work?
3. Will comp 918's work with stock retainers? If not is there any significant difference between Comps steel retainers vs there titanium besides weight?
4. Oil pump- Should I replace? Still has 45psi at idle warm and over 60psi while driving.
5. Lifters? Stock ones ok or should I go LS7?
6. Other than pushrods anything else I should address while Im in there?
Any thoughts will be greatly appreciatted, Thanks-

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dont need unless you have alot of slack in yous
2 not ness.
3should get titanium retainers.but stock will work
4 not ness ,but if yoour pulling the pan ,change the oring on the pickup tube.
5 stock 1s are fine.
good luck

Quote:

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Originally Posted by LS6 Silverado

Ok have a few questions about installing a comp cam in my 02 silverado 5.3l- Cam is the Comp XR265HR- Motor has 82K miles.

1. Will I need a new timing set from Comp so I can degree the cam?
2. Is it even necassary to degree the cam? Will stock timing gears/chain work?
3. Will comp 918's work with stock retainers? If not is there any significant difference between Comps steel retainers vs there titanium besides weight?
4. Oil pump- Should I replace? Still has 45psi at idle warm and over 60psi while driving.
5. Lifters? Stock ones ok or should I go LS7?
6. Other than pushrods anything else I should address while Im in there?
Any thoughts will be greatly appreciatted, Thanks-

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Did this same swap a few months ago.

1. & 2. A timing set will not be necessary for your swap. As long as your not changing the timing set, I wouldn't touch the oil pump(4.). The less you take apart, the better off you are.
3. I'm using 918's with stock retainers and they're more than adequate.
5. & 6. The only things I changed with my cam swap were the cam and the springs. Unless that cam has a smaller than stock base circle, everything should work perfectly.

Quote:

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Originally Posted by LS6 Silverado

Ok have a few questions about installing a comp cam in my 02 silverado 5.3l- Cam is the Comp XR265HR- Motor has 82K miles.

1. Will I need a new timing set from Comp so I can degree the cam?
2. Is it even necassary to degree the cam? Will stock timing gears/chain work?
3. Will comp 918's work with stock retainers? If not is there any significant difference between Comps steel retainers vs there titanium besides weight?
4. Oil pump- Should I replace? Still has 45psi at idle warm and over 60psi while driving.
5. Lifters? Stock ones ok or should I go LS7?
6. Other than pushrods anything else I should address while Im in there?
Any thoughts will be greatly appreciatted, Thanks-

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BTW - i have the spring tool and lifter hold rods you will need for sale in the classifieds section.

Also google "LS1 cam swap" and you will find a step by step article.

1. Will I need a new timing set from Comp so I can degree the cam?
NO. Unless the chain is extremely sloppy, then get a new timing chain and gear.

2. Is it even necassary to degree the cam? Will stock timing gears/chain work?
Before you take the cam out, you have to align the cam gear with the crank gear do that it is at TDC. The ls1howto.com article shows how to do this.

3. Will comp 918's work with stock retainers? If not is there any significant difference between Comps steel retainers vs there titanium besides weight?
Yes, the 918's will work with stock retainers just fine.

4. Oil pump- Should I replace? Still has 45psi at idle warm and over 60psi while driving.
Nope. Everything looks fine psi-wise.

5. Lifters? Stock ones ok or should I go LS7?
Lifters are fine.

6. Other than pushrods anything else I should address while Im in there?
Read the ls1howto.com article. If you have any other questions, feel free to PM one of us.

Thanks for the info guys- SS, the cam does have a smaller base circle. It showed up yesterday and I busted out the mics heres what I found- Stock LM7 cam has a 1.552" base circle while the Comp has a 1.497" base circle. A difference of .055"- Works out to be a pushrod length difference of 27.5 thousandths. So heres my plan, While installing my headers the rearmost bolt broke off on the driver bank so I Have a spare set of low milage 862 casting heads that im gonna have milled .010 - .015 and possibly have the rocker pads shaved .005"- Should put me close enough to use stock pushrods and bump compression a bit. (given the fel-pro mls gaskets have the same compressed thickness which Im pretty sure they do) Gonna replace the valve seals and should be good to go- As far as timing set if everyone is using the stock stuff maybe I will just put in the beefier ls2 chain and call it good- Do you have to pull the oil pump to get the chain off? Any other thoughts? Thanks guys-

Quote:

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Originally Posted by LS6 Silverado

Thanks for the info guys- SS, the cam does have a smaller base circle. It showed up yesterday and I busted out the mics heres what I found- Stock LM7 cam has a 1.552" base circle while the Comp has a 1.497" base circle. A difference of .055"- Works out to be a pushrod length difference of 27.5 thousandths. So heres my plan, While installing my headers the rearmost bolt broke off on the driver bank so I Have a spare set of low milage 862 casting heads that im gonna have milled .010 - .015 and possibly have the rocker pads shaved .005"- Should put me close enough to use stock pushrods and bump compression a bit. (given the fel-pro mls gaskets have the same compressed thickness which Im pretty sure they do) Gonna replace the valve seals and should be good to go- As far as timing set if everyone is using the stock stuff maybe I will just put in the beefier ls2 chain and call it good- Do you have to pull the oil pump to get the chain off? Any other thoughts? Thanks guys-

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I did put the stock LS2 timing set on my 5.3L... we changed the oil pump too (110,000 miles). You do have to remove the oil pump to gain access to the timing set. We managed to accomplish this without removing the oil pan but there is one bolt on the pick-up tub that makes this very tricky. I dropped the bolt into the front of the oil pan a couple times but we were able to fish it out with a magnet. If the bolt falls back into the bottom of the pan, expect to be dropping an oil pan to retreive it. Oil pump, cam, timing set and springs took about 3 hours.

its not necessary to degree the cam, but doing so will set the cam to the true specs. The specs on the cam card are off by a degree or two than what the cam is ground to. You'll pick up a couple free horsepower. A drill and degree kit is all you need. But its better to have someone do it if you've never done it