Cam Motion Blower Cam Install
11-13-2004, 09:59 PM
#1
TECH Veteran
Thread Starter
Cam Motion Blower Cam Install
This post chronicles the installation of a custom-spec’d blower cam from Cam Motion and the results of that install. It is broken up into sections so that people who only want to read a particular section can go to that section. The areas covered are (1) Cam Selection Criteria, (2) Cam Installation, (3) Dyno Run/Track Times
Cam Selection Criteria
After shopping for a cam for over 4 months, I arrived on a custom cam from Cam Motion. As many people know, Cam Motion makes the custom cams for Futral Motorsports as well as some other performance shops. Anyone who knows LS1’s and cams knows that Cam Motion is a player, albeit more behind the scenes than Comp or the other manufacturers. But this does not mean that they don’t know what they’re doing...on the contrary, they have significant knowledge not only in LS1 cars, but trucks as well. This is why I consulted with them originally, and after weeks and numerous phone calls back and forth to a lead tech, why I chose a cam for my blown Avalanche from them.
Most people in the performance world seem to operate under the premise that more is better, which of course finds its way into the area of camshaft selection. However, with automatic transmissions, once you start looking at high-duration camshafts, you also end up looking at aftermarket torque converters with higher than stock stall speeds, since you end up shifting the powerband upward on the RPM scale with the more duration you have. Usually we’re talking a minimum of a 2500-2600 RPM stall, but many times you must get into the 3000-3200 RPM range just to experience usable power. For me this was not going to work, as I wanted to leave the stock torque converter in the truck, for a couple of reasons.
One reason was that, if I ever decided to sell my truck, I wanted to be able to sell it with all the stock capacities (i.e. payload, towing) intact. I didn’t want to have to deal with doing a reverse cam swap in order to sell it to someone who wanted a truck they could use as a truck - let’s say, to tow 7,000 lbs with. The other reason was that I did not want to deal with aftermarket torque converters. TC’s seemed like a crap shoot to me...some people had luck with them, others didn’t, and there seemed to be significant labor involved in dealing with those situations that didn’t turn out so well. I wanted to skip that potential bag of worms altogether by just retaining the stock TC. So, swapping the TC out was not an option for me, and as a result, I was, by default, limiting myself to lower duration cams.
In the end, people really in the know pretty much agreed that a 206/212 cam was as big as I could go in my 5.3L while giving me what I wanted – high torque at low RPM’s (right off idle), while retaining my stock torque converter. Problem was, Comp’s only offering in this area was a 206/212 low-lift cam, with lobes measuring in at .522/.529. In my quest for info I also spoke with some experienced engine builders (like Chris at APE, Allan at Futral) who said that with a blower and stock heads, higher lift was desirable, with more intake lift than exhaust lift. This is where Terry at Cam Motion came through. He said he would make me a 205/211, .550/.544 cam on a 114 LSA, with 4 degrees of advance. With a truck as heavy as mine (6,000 lbs), that was as big as said he would recommend. I decided to go for it, and ordered the cam.
The final specs on the cam I received were as follows:
Lobe Separation = 114 cam deg
Valve Overlap = -18.6 crank deg
INTAKE
valve open = -8.1 BTDC
centerline = 110 ATDC
valve close = 33.1 ABDC
duration = 205 crank deg
lobe lift = .32236 in.
valve lift = .54802 in.
lobe area = 23.19 in * deg
EXHAUST
valve open = 42.8 BBDC
centerline = 118 BTDC
valve close = -10.4 ATDC
duration = 212.4 crank deg
lobe lift = .31728 in.
valve lift = .53938 in.
lobe area = 23.64 in * deg
Cam Installation
I have never installed a cam before in my life, so I was going to need some help. Two guys agreed to assist with the install – jrp (from F-body & Internal Engine fame), and moregrip (from right here in the truck section). jrp stopped over for a preliminary look at the truck two weeks prior to install, since he had never done a truck cam before. After seeing the available room under the hood, and being satisfied that my LM7 was enough like the LS1’s he had worked on before, agreed to spearhead the effort, while moregrip graciously agreed to host the event in the garage at his place and provide the refreshments.
Install took a while. We followed the ‘LS1 How To’ nearly to the letter. We ran into some minor issues that ended up taking time, like not getting the pulley puller on the crank pulley properly and struggling with that, and not putting lock-tite on the rocker screws and having to back them out and put them back in again, but in spite of these and other, realtively minor issues, the install was uneventful, if not time consuming. We used triple insurance for dropped lifters: spinning the cam (Russian Roulette), pen magnets, and metal rod stock from Home Depot (3/8” and 5/16”) in case the lifters fell. We couldn’t get either of the rods all the way into the driver’s side, so when the time came, we just prayed and pulled the old cam out and slid the new one in. I didn’t realize how nervous I had been until I saw (and heard) the new cam click into place.
It took us a couple of tries with the timing chain to get proper dot-to-dot lineup on the new cam. Once we were confident, I spun the crank around 360* to make sure we were spot-on. That was fun with all the spark plugs in, fighting compression. Turn, wait. Turn, wait. Springs were somewhat time consuming. I used the Sears spring compressor on the driver’s side while jrp used a more elaborate tool (from SDPC I believe) on the passenger side. I had a couple-three instances of springs and retainers flying out of that Sears tool….gotta be careful with that thing if you use it. We reused the stock retainers and locks – didn’t lose any, which was nice, though we had spares on hand just in case.
Some need-to-have tools: Torque wrenches....we used two. One was inch-pounds that we converted to foot-pounds for low torque requirements, the other was larger for the others. Breaker bars....we used two. Couldn’t have done the installation without them. Invaluable for getting the crank pulley bolt off, and back on. Longer crank pulley bolt....required to get the crank pulley started back on. I got mine from McMaster Carr, part number 91310A868. Heavy-duty grease to put on the locks when reinstalling them....hate to see how many locks we would have lost without it. Little dab on each lock, then Voila! (Well, almost). Pen magnets....not just for securing the lifters, also invaluable for retrieving locks once the springs were compressed. Very handy.
All-in-all, a pretty straightforward operation. It took us longer than it probably needed to, but we were more careful than careless throughout the entire operation. When there was doubt, we backed up and double-checked. The reward was, no leaks or problems when the engine was fired up. (Hint: turn off you’re A/C before you start the cam swap, so when you start your newly-cammed motor up again, you don’t wonder why it’s surging like it is...). Tremendous thanks go out to jrp, who volunteered his valuable time, energy, expertise, and toolset, and to moregrip, for the use of his facilities, extensive toolset, knowledge, and very helpful suggestions along the way
. A special thanks goes out to mrs. moregrip, who took over sick dog duty for a whole day, and saw fit to order a pizza for the guys who barely wanted to drink water or Coke throughout the whole exercise. Thanks! 
Dyno Run/Track Times
Today was to have been the day to go to the dyno in Santee and then directly to the track in Fontana to get results of this cam install. My last dyno run was 338 RWHP/365 RWTQ in June of this year. The only mod since then would have been the cam. However, a minor mishap this morning (umm, stock aluminum driveshaft sheared in half
) cut the first dyno run short, and eliminated the possibility of a track run in Fontana. So we will have to wait for track/dyno results. SOTP, however, is a different story, no numbers needed for that. In the two weeks since the cam install, every passenger that had ridden in the truck before, immediately noticed a difference in off-the-line acceleration and torque. “Holy Sh@#!” was a common refrain amongst them. Immediately after installing the cam, any thoughts I had about needing an aftermarket torque converter - or 4.10 gears rather than the stock 3.73’s - immediately went away. There is instant boost and torque, literally from idle, onward and upward to 6K. This cam is a perfect complement to the Radix, and I would not hesitate to recommend it to anyone who wants to keep their stock TC, either for a N/A or a boosted application. It just plain rocks.
Thanks go out to Terry from Cam Motion, who convinced me that smaller is sometimes better. You were right.
Cam Selection Criteria
After shopping for a cam for over 4 months, I arrived on a custom cam from Cam Motion. As many people know, Cam Motion makes the custom cams for Futral Motorsports as well as some other performance shops. Anyone who knows LS1’s and cams knows that Cam Motion is a player, albeit more behind the scenes than Comp or the other manufacturers. But this does not mean that they don’t know what they’re doing...on the contrary, they have significant knowledge not only in LS1 cars, but trucks as well. This is why I consulted with them originally, and after weeks and numerous phone calls back and forth to a lead tech, why I chose a cam for my blown Avalanche from them.
Most people in the performance world seem to operate under the premise that more is better, which of course finds its way into the area of camshaft selection. However, with automatic transmissions, once you start looking at high-duration camshafts, you also end up looking at aftermarket torque converters with higher than stock stall speeds, since you end up shifting the powerband upward on the RPM scale with the more duration you have. Usually we’re talking a minimum of a 2500-2600 RPM stall, but many times you must get into the 3000-3200 RPM range just to experience usable power. For me this was not going to work, as I wanted to leave the stock torque converter in the truck, for a couple of reasons.
One reason was that, if I ever decided to sell my truck, I wanted to be able to sell it with all the stock capacities (i.e. payload, towing) intact. I didn’t want to have to deal with doing a reverse cam swap in order to sell it to someone who wanted a truck they could use as a truck - let’s say, to tow 7,000 lbs with. The other reason was that I did not want to deal with aftermarket torque converters. TC’s seemed like a crap shoot to me...some people had luck with them, others didn’t, and there seemed to be significant labor involved in dealing with those situations that didn’t turn out so well. I wanted to skip that potential bag of worms altogether by just retaining the stock TC. So, swapping the TC out was not an option for me, and as a result, I was, by default, limiting myself to lower duration cams.
In the end, people really in the know pretty much agreed that a 206/212 cam was as big as I could go in my 5.3L while giving me what I wanted – high torque at low RPM’s (right off idle), while retaining my stock torque converter. Problem was, Comp’s only offering in this area was a 206/212 low-lift cam, with lobes measuring in at .522/.529. In my quest for info I also spoke with some experienced engine builders (like Chris at APE, Allan at Futral) who said that with a blower and stock heads, higher lift was desirable, with more intake lift than exhaust lift. This is where Terry at Cam Motion came through. He said he would make me a 205/211, .550/.544 cam on a 114 LSA, with 4 degrees of advance. With a truck as heavy as mine (6,000 lbs), that was as big as said he would recommend. I decided to go for it, and ordered the cam.
The final specs on the cam I received were as follows:
Lobe Separation = 114 cam deg
Valve Overlap = -18.6 crank deg
INTAKE
valve open = -8.1 BTDC
centerline = 110 ATDC
valve close = 33.1 ABDC
duration = 205 crank deg
lobe lift = .32236 in.
valve lift = .54802 in.
lobe area = 23.19 in * deg
EXHAUST
valve open = 42.8 BBDC
centerline = 118 BTDC
valve close = -10.4 ATDC
duration = 212.4 crank deg
lobe lift = .31728 in.
valve lift = .53938 in.
lobe area = 23.64 in * deg
Cam Installation
I have never installed a cam before in my life, so I was going to need some help. Two guys agreed to assist with the install – jrp (from F-body & Internal Engine fame), and moregrip (from right here in the truck section). jrp stopped over for a preliminary look at the truck two weeks prior to install, since he had never done a truck cam before. After seeing the available room under the hood, and being satisfied that my LM7 was enough like the LS1’s he had worked on before, agreed to spearhead the effort, while moregrip graciously agreed to host the event in the garage at his place and provide the refreshments.
Install took a while. We followed the ‘LS1 How To’ nearly to the letter. We ran into some minor issues that ended up taking time, like not getting the pulley puller on the crank pulley properly and struggling with that, and not putting lock-tite on the rocker screws and having to back them out and put them back in again, but in spite of these and other, realtively minor issues, the install was uneventful, if not time consuming. We used triple insurance for dropped lifters: spinning the cam (Russian Roulette), pen magnets, and metal rod stock from Home Depot (3/8” and 5/16”) in case the lifters fell. We couldn’t get either of the rods all the way into the driver’s side, so when the time came, we just prayed and pulled the old cam out and slid the new one in. I didn’t realize how nervous I had been until I saw (and heard) the new cam click into place.
It took us a couple of tries with the timing chain to get proper dot-to-dot lineup on the new cam. Once we were confident, I spun the crank around 360* to make sure we were spot-on. That was fun with all the spark plugs in, fighting compression. Turn, wait. Turn, wait. Springs were somewhat time consuming. I used the Sears spring compressor on the driver’s side while jrp used a more elaborate tool (from SDPC I believe) on the passenger side. I had a couple-three instances of springs and retainers flying out of that Sears tool….gotta be careful with that thing if you use it. We reused the stock retainers and locks – didn’t lose any, which was nice, though we had spares on hand just in case.
Some need-to-have tools: Torque wrenches....we used two. One was inch-pounds that we converted to foot-pounds for low torque requirements, the other was larger for the others. Breaker bars....we used two. Couldn’t have done the installation without them. Invaluable for getting the crank pulley bolt off, and back on. Longer crank pulley bolt....required to get the crank pulley started back on. I got mine from McMaster Carr, part number 91310A868. Heavy-duty grease to put on the locks when reinstalling them....hate to see how many locks we would have lost without it. Little dab on each lock, then Voila! (Well, almost). Pen magnets....not just for securing the lifters, also invaluable for retrieving locks once the springs were compressed. Very handy.
All-in-all, a pretty straightforward operation. It took us longer than it probably needed to, but we were more careful than careless throughout the entire operation. When there was doubt, we backed up and double-checked. The reward was, no leaks or problems when the engine was fired up. (Hint: turn off you’re A/C before you start the cam swap, so when you start your newly-cammed motor up again, you don’t wonder why it’s surging like it is...). Tremendous thanks go out to jrp, who volunteered his valuable time, energy, expertise, and toolset, and to moregrip, for the use of his facilities, extensive toolset, knowledge, and very helpful suggestions along the way
. A special thanks goes out to mrs. moregrip, who took over sick dog duty for a whole day, and saw fit to order a pizza for the guys who barely wanted to drink water or Coke throughout the whole exercise. Thanks! Dyno Run/Track Times
Today was to have been the day to go to the dyno in Santee and then directly to the track in Fontana to get results of this cam install. My last dyno run was 338 RWHP/365 RWTQ in June of this year. The only mod since then would have been the cam. However, a minor mishap this morning (umm, stock aluminum driveshaft sheared in half
) cut the first dyno run short, and eliminated the possibility of a track run in Fontana. So we will have to wait for track/dyno results. SOTP, however, is a different story, no numbers needed for that. In the two weeks since the cam install, every passenger that had ridden in the truck before, immediately noticed a difference in off-the-line acceleration and torque. “Holy Sh@#!” was a common refrain amongst them. Immediately after installing the cam, any thoughts I had about needing an aftermarket torque converter - or 4.10 gears rather than the stock 3.73’s - immediately went away. There is instant boost and torque, literally from idle, onward and upward to 6K. This cam is a perfect complement to the Radix, and I would not hesitate to recommend it to anyone who wants to keep their stock TC, either for a N/A or a boosted application. It just plain rocks. Thanks go out to Terry from Cam Motion, who convinced me that smaller is sometimes better. You were right.
11-13-2004, 10:20 PM
#2
No worries , it was fun 
, although long 
, and has convinced me to do a Cam myself sometime in the future 
We had a good time installing it. Lots of laughs too
.
What Naked is not telling you is, while his driveshaft did eject itself promtly from beneath his AV this morning, his truck was absolutely screaming on the Dynojet Dyno laying down Northwards of 475ftlbs of Torque! HolyShit!!!
, it was fun , although long , and has convinced me to do a Cam myself sometime in the future We had a good time installing it. Lots of laughs too
.What Naked is not telling you is, while his driveshaft did eject itself promtly from beneath his AV this morning, his truck was absolutely screaming on the Dynojet Dyno laying down Northwards of 475ftlbs of Torque! HolyShit!!!
11-14-2004, 11:54 AM
#6
TECH Veteran
Thread Starter
Originally Posted by raisinkane
Was there any tuning required for your cam?
raisin
raisin
Comparing the two dynos, I gained anywhere from 12-18 RWHP/RWTQ from the cam. But that is only part of the story....the SOTP gain was amazing, especially off idle.
11-14-2004, 12:10 PM
#7
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Great write up....I've been reading all the cam threads lately - starting my research on cams. So far I've figured out what all those numbers mean, well most
Do you have the Radix Superchips tune? Is there any need to up the shift points?
Do you have the Radix Superchips tune? Is there any need to up the shift points?
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11-14-2004, 12:36 PM
#9
TECH Veteran
Thread Starter
Yes, I have the stock Radix Superchips tune. No need to up the shift points, if you don't want to.
I haven't changed the idle at all. Looking in my HPT .bin file, idle in gear varies with coolant temp....from 800 rpms at 68* to 600 rpms at 177*.
I haven't changed the idle at all. Looking in my HPT .bin file, idle in gear varies with coolant temp....from 800 rpms at 68* to 600 rpms at 177*.