Degreeing in your cams. Important!
#1
Degreeing in your cams. Important!
My engine assembler has done a lot of High end LSx, GT500, installs and he near insisted on degree'ing in my new cam. I'm a proponent anyway so it wasn't anything odd. He mentioned he's came across quite a few cams that, even with new timing chains, gears, cams, etc, where the cam was off by as much as 8 to 9 degrees when installed "straight up".
My new cam, chain, gears, were off by 5 degrees. He drilled out the hole on the sprocket, put in the eccentric and dialed it back in to the cam cards spec's.
I've seen a lot of guys go on faith and just install the cams with the sprockets at 12/6. My assembler said he's had the best consistency with one brand (he told me but I don't want to come off as public proponent of the company) and the worst was another company(the one that has the 8 to 9 degrees off spec).
I've degreed my own cams before and have the tools and experience to do my own but since my assembler has the engine for all the other machining, etc and is a 45 minute drive away, I let him do this one
Looks like the turbo ready 5.3 *may* be ready for pickup this coming weekend. He's having a bud weld a -10AN bung to my new Fbody Oil pan for the turbo drain.
Once I pick it up, I'll chuck in onto my engine stand, put the hotside and turbo on it and take some pictures. Temps are just now trending from teens to the 30's so hopefully, Spring like weather will let me get out there and start assembling this rocket.
I may put my new transbraked TH350 onto the existing LT1 turbo setup for a pass or two to see how it runs with the automatic before putting in the 5.3 stuff.
My new cam, chain, gears, were off by 5 degrees. He drilled out the hole on the sprocket, put in the eccentric and dialed it back in to the cam cards spec's.
I've seen a lot of guys go on faith and just install the cams with the sprockets at 12/6. My assembler said he's had the best consistency with one brand (he told me but I don't want to come off as public proponent of the company) and the worst was another company(the one that has the 8 to 9 degrees off spec).
I've degreed my own cams before and have the tools and experience to do my own but since my assembler has the engine for all the other machining, etc and is a 45 minute drive away, I let him do this one
Looks like the turbo ready 5.3 *may* be ready for pickup this coming weekend. He's having a bud weld a -10AN bung to my new Fbody Oil pan for the turbo drain.
Once I pick it up, I'll chuck in onto my engine stand, put the hotside and turbo on it and take some pictures. Temps are just now trending from teens to the 30's so hopefully, Spring like weather will let me get out there and start assembling this rocket.
I may put my new transbraked TH350 onto the existing LT1 turbo setup for a pass or two to see how it runs with the automatic before putting in the 5.3 stuff.
#5
youd be surprised how many cams are not ground correctly from the plant.
out of basically 10 cams in the last couple years ive seen one degree on the money, and it was the one in my car.
1/2 a degree off.
worst one was off almost 8 degrees. if youve ever seen an engine loose 100hp from a cam, thatd be the one to watch it happen to.
out of basically 10 cams in the last couple years ive seen one degree on the money, and it was the one in my car.
1/2 a degree off.
worst one was off almost 8 degrees. if youve ever seen an engine loose 100hp from a cam, thatd be the one to watch it happen to.
#7
Here's a middle of the road expense cam degree kit.
http://www.jegs.com/i/JEGS/555/81621...FZSKaQodb2sA0g
This is the one I used back in 2008.
The procedure can vary a bit, depending on lifter type and if the heads are on the motor or not.
Ideally you do it while the motor is on the stand.
Here's a quick video overview. There's important things that aren't stated here like...
After you watch this video, the followup one that plays immediately afterwards is somewhat helpful too.
http://www.jegs.com/i/JEGS/555/81621...FZSKaQodb2sA0g
This is the one I used back in 2008.
The procedure can vary a bit, depending on lifter type and if the heads are on the motor or not.
Ideally you do it while the motor is on the stand.
Here's a quick video overview. There's important things that aren't stated here like...
- Removing all load off the crank (no spark plugs, pushrods off, etc). This is so you can easily turn the crank without it jerking around trying to overcome compression, valve spring resistance, etc.
- Making sure you establish Top dead Center accurately
- Making sure your dial indicator is zero'd at the correct point and in alignment with the lifter
- How to affect the correction when you DO find your cam is off
- Etc...
After you watch this video, the followup one that plays immediately afterwards is somewhat helpful too.
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#9
TECH Apprentice
"My new cam, chain, gears, were off by 5 degrees. He drilled out the hole on the sprocket, put in the eccentric and dialed it back in to the cam cards spec's. "
Can you elaborate on this? Lets say i degree my cam and its off by quite a bit, is there a way to do this without a $190 adjustable sprocket set? Sorry for the rookie questions, learning as i go.
Can you elaborate on this? Lets say i degree my cam and its off by quite a bit, is there a way to do this without a $190 adjustable sprocket set? Sorry for the rookie questions, learning as i go.
#10
Well, it would have to be within a reasonable/recoverable range. I found this.. http://www.superchevy.com/how-to/050...m/viewall.html
Even better, go here, about 1/3rd of the way down on rotating an eccentric.
http://www.powerperformancenews.com/...ls-cam-timing/
Even better, go here, about 1/3rd of the way down on rotating an eccentric.
http://www.powerperformancenews.com/...ls-cam-timing/
Last edited by mightyquickz28; 03-03-2015 at 06:40 PM.
#13
#15
I wonder how many people that don't do it every day, do it wrong. I just read and watched multiple videos on how to correctly degree a cam, also said that with a cam with ground in advance is not as accurate in the degree process and is not really needed. I am no engine builder tho, not sure how true that is.
#16
9 Second Club
Of course the other aspect is...
Will say 2 deg really make any difference ? I'd honestly say no.
Will the chain stretch over time ? I'd definitely say yes. So do you time as per card, do you time to allow for some stretch, or do you just bang it in any old place lol
Will say 2 deg really make any difference ? I'd honestly say no.
Will the chain stretch over time ? I'd definitely say yes. So do you time as per card, do you time to allow for some stretch, or do you just bang it in any old place lol
#17
8 Second Club
iTrader: (4)
I had a cam come in 8+* retarded installed dot-to-dot. Was a 2008 5.3. Was originally a DOD engine, the cam I installed was not. Pulled the same cam and tried it on an older 2006 4.8. It was within a degree installed Dot-to-dot. Used the same Cloyes billet single timing set. I believe this was due to my crank key.
The engine was down 100+ HP on the 5.3 initially. Advanced 8* and it preformed great at that point. Went from 145ish to 195-200 cranking PSI. Pulled the same cam and installed in a 2006 later that year and installed it straight up. The 4.8 performed great.
Just pointing out it may not always be a cam problem. My first thought was to blame the cam as well.
The engine was down 100+ HP on the 5.3 initially. Advanced 8* and it preformed great at that point. Went from 145ish to 195-200 cranking PSI. Pulled the same cam and installed in a 2006 later that year and installed it straight up. The 4.8 performed great.
Just pointing out it may not always be a cam problem. My first thought was to blame the cam as well.
#19
I had one from comp that wasn't even the right lobe. It degreed correctly for icl, but was 9 degrees bigger duration and .017 bigger lift. It came with a cam card with the correct lift and duration. And the cam was engraved with the #'s from the cam card. Would have been a total **** show if I didn't check it.
Ryan
Ryan