ICL on stock ls cams

[racin69z]

I am rebuilding the stock 260k mile lq4 in my 2002 2500hd. I do quite a bit of heavy towing and would really like a torque boost around 2500-3000 rpm. I am looking for a budget friendly cam. I'd love to buy a comp, or btr, or cam motion $400 cam but that just seems crazy. My race car solid roller cam didn't cost that much.

Alot of people are happy with their 206 212 112 or 212 218 114 or 112 cams. I've read discussions where people say the stock ls2 or ls6 cams simply dont work well in a truck. They are both very similar to the previously mentioned aftermarket cams in .050 duration. The lobe sep is about 5 degrees wider than the aftermarket cams. But, comps truck cams are on a 115 lobe sep. I am pretty sure that a 112 should help with low end torque.

Sorry for the long backstory. Here is my question. Could it be that the stock gm cams are just ground with a retarded icl? If I were to use an offset cam dowel bushing and put the gm cams on a 112 or so icl would that move the powerband down to the right level?

And maybe its just that the seat to seat duration is wildly different on the gm cams or some kind of asymmetric lobe design altering the valve events. I read a post on here about the stock ls series cams and the late ICL but it really didnt pertain to a truck type build. I kind of think people now adays just have the mentality that you have to have the latest shiney name brand gadget and anything else is garbage. If you spend $400 on a cam your butt dyno is going to tell you it made an improvement. I like resurrecting the dead and making things work on the cheap. But I also realized that some crap just don't work and if so, I'll buy what is needed.

Many years ago in my 69 Camaro with a 11.5:1 377 I did a bunch of track testing with crane solid flat tappets all the way from 244 @050 to 265 @050 and it ran a little different but it wasn't crazy different. Maybe a tenth or 2 in the 1/8. And maybe I'm way off but it seems like a couple degrees here and there really doesn't make a huge difference.

Any input or discussion would be great.

Thanks
Lynn

[induction apprentice]

Great question.
I have a mint low mile LS6 CAM I was thinking of putting in my 6.0 L truck when I freshen it soon. So I also am interested in this

[F-BIRD'88]

You will get a much more meaningfull real gain (especially when towing) by changing the rear gear ratio in the truck. X2 if the tires are taller than oem.

[CGT]

I am rebuilding the stock 260k mile lq4 in my 2002 2500hd. I do quite a bit of heavy towing and would really like a torque boost around 2500-3000 rpm. I am looking for a budget friendly cam. I'd love to buy a comp, or btr, or cam motion $400 cam but that just seems crazy. My race car solid roller cam didn't cost that much.

Alot of people are happy with their 206 212 112 or 212 218 114 or 112 cams. I've read discussions where people say the stock ls2 or ls6 cams simply dont work well in a truck. They are both very similar to the previously mentioned aftermarket cams in .050 duration. The lobe sep is about 5 degrees wider than the aftermarket cams. But, comps truck cams are on a 115 lobe sep. I am pretty sure that a 112 should help with low end torque.

Sorry for the long backstory. Here is my question. Could it be that the stock gm cams are just ground with a retarded icl? If I were to use an offset cam dowel bushing and put the gm cams on a 112 or so icl would that move the powerband down to the right level?

And maybe its just that the seat to seat duration is wildly different on the gm cams or some kind of asymmetric lobe design altering the valve events. I read a post on here about the stock ls series cams and the late ICL but it really didnt pertain to a truck type build. I kind of think people now adays just have the mentality that you have to have the latest shiney name brand gadget and anything else is garbage. If you spend $400 on a cam your butt dyno is going to tell you it made an improvement. I like resurrecting the dead and making things work on the cheap. But I also realized that some crap just don't work and if so, I'll buy what is needed.

Many years ago in my 69 Camaro with a 11.5:1 377 I did a bunch of track testing with crane solid flat tappets all the way from 244 @050 to 265 @050 and it ran a little different but it wasn't crazy different. Maybe a tenth or 2 in the 1/8. And maybe I'm way off but it seems like a couple degrees here and there really doesn't make a huge difference.

Any input or discussion would be great.

Thanks
Lynn

I've played around with quite a few LS's, but I have never really plotted a stock cam or checked the ICL as from GM. I get what your trying to do and I think an aftermarket cam is not really gonna show much of any in your towing rpm range. It may me possible to put a little advance in the stock cam and help your cause some.

It would be as easy as mocking it up with the stock gear set and see where its at.

[DSRE388]

My 99 3 door 6.0 truck 2500 had the cast iron heads, used the same exact cam used in 4.8/5.3's and would smoke the 04 6.0 truck that had a bigger cam from the factory
The 5.3 cam is 192in 190ex .440ish lift 114lsa 116ilc iirc
The cam went up to iirc 196in 202ex .465ish lift 116lsa and it was a dog comparatively. This was about 9-10 years ago that i was pretty involved with factory cams. I know one of the factory stock LS1 cams did pretty good but the LS6 cams were DOGS down low in the truck engines, ive noticed most the time on very wide lobe separation cams you lose power advancing them more than 2-3*
But yes i know many of the factory cams were installed with a retarded ilc

[rfoll]

"latest shiney name brand gadget". What you really need is a bootlegger, black ice streetforce, rattler, thumper, or voodoo.

[racin69z]

I have 4.10 gears with 285 tires which are larger, but from an RPM standpoint I like it better than when it had 245s. It just sang the motor more with the smaller tires. It seems like the ls is just like any other small block no torque below 3k. I know I'm never going to have good mileage with this setup while towing so maybe i just need to bite the bullet and do a cheap turbo setup. They are trying to end vehicle safety inspections in my state if they do I wont have to worry about cats.

"Bootlegger, black ice streetforce, rattler, thumper, or voodoo"
Exactly! I've saw it on discussions time and time again.


Interesting info about the early cam. For the time being I could try the late lq4 cam a couple degrees advanced.

Thanks for the input
Lynn

[F-BIRD'88]

With the now non stock taller tires your effective gear ratio and cruising rpm ;s now 16% lower. This is why you are missing REAL running/towing → TORQUE ←.

Put the stock size (diameter) tires back on. (When towing).

You are not going to fix this with a cam, at any price.

[fastblackracing]

I have 4.10 gears with 285 tires which are larger, but from an RPM standpoint I like it better than when it had 245s. It just sang the motor more with the smaller tires. It seems like the ls is just like any other small block no torque below 3k. I know I'm never going to have good mileage with this setup while towing so maybe i just need to bite the bullet and do a cheap turbo setup. They are trying to end vehicle safety inspections in my state if they do I wont have to worry about cats.

"Bootlegger, black ice streetforce, rattler, thumper, or voodoo"
Exactly! I've saw it on discussions time and time again.


Interesting info about the early cam. For the time being I could try the late lq4 cam a couple degrees advanced.

Thanks for the input
Lynn

Every stock Ls engine I have ever driven has been lacking in torque under 3500rpm.....
Wide lobe centers, and generous intake ports are major factors IMO.

My old 72' monte carlo 350 with the "929" cam would waste one of these modern LS engines
up to 4000 rpm or so.....

There may be some real gains to be had by choosing a cam with specs more suited for
low end/mid range say 198/205 on a 107LSA....at the expense of some upstairs power
most likely.

I know if I had one for a daily driver I would be looking to cam it better, sure they run
decent over 4k but they suck down low.

What are the truck cam specs from Tooley?

[racin69z]

F-Bird. I definitely agree with you. It will tow better with 245 tires no doubt. But, I like the way it looks with the larger tires and I am willing to deal with that loss and try to make up for it in other ways. I do appreciate your input.

BTR has several different cams. They have a 206 212 on a 114 and a 20x 20x on a 111. And they get bigger from there.

There is a melling cam that comparitively pretty budget friendly ($270) on rock auto after discount code. Still seems like a ton for a truck cam. Its 206 212 on a 112. 515 521 lift. Should be easy on springs. I could run it on a 108-110 icl and it may shake out pretty good. Without knowing seat to seat duration and going off of the .050 numbers, the melling on a 110 icl will close the intake valve 2* sooner which should trap a little more volume which should help build a little more low end torque. It also has more duration which should help with higher rpm cylinder filling.

The smaller early lq4 cam that DSRE388 mentioned earlier closes the intake valve 4.5* sooner which may explain the butt dyno torque gains.

Fastblack, I've never ran anything with a 929 but I've ran the 204 214 112 and a bunch from there up and none of them really sat the world on fire. It seems like 350-364 ci torque production just isn't great below 3k. I had the 204 214 112 420 443 in a 8.3:1 350. It ran good. Once I realized that they were reduced deckheight rebuilder pistons and that my compression was so low, I decked the block and got it up to 9.25:1 and it was a whole different motor.

I later built that block into a 10.2:1 (really wanted 9.5:1 but block was decked too much) 383 with a 216 216 110 450 450 crane Energizer. It was a towing beast, but was real picky with timing and fuel. Had to leave it in gear when I shut it off if I had the timing where it ran best.

I dont know how close to detonation the lq4 engine is from the factory, but the lq9 has more compression with the same cam.

I bought hp tuners and am willing to take the time to mess with it.

Sorry to ramble on, but I like a good discussion.

Lynn

[Ozonkiller]

Degree it and find out where you are. That may give you the answer.
I agree. My wife's '03 1500 goes like stink if you rev it but has no low end or midrange torque. Annoying as hell, here in the mountains of Arizona

[68post]

As an extreme example of this is what I consider my 2005 3500 Express 10' cube van with it's original 4.8 and single rear wheels, bought used. It drives off idle like a good straight six,( in an empty 1/2 ton truck), from years ago, but past 4,000/4,500 if your foot is in it it will sing.
The 4.10s need to be either 4.56 or 4.88, or it needed at least a 5.3 or 6.0. We run slightly heavy (half full always) to heavy when hauling garage doors.
Good thing this doesn't have a trailer hitch - I may be tempted to pull mine with it.
Most of the regular vans around this age have a 6.0,(only options in 2005: gas only;4.8 or 6.0/6.0 NG) and they just complain about gas mileage but not a lack of power. Everyone likes,raves about, their 4.8 in their empty pickup, but are mum when I speakup.

I remember mine drives great when empty, and if that was what it's use it would be fine. I drove it empty for 25 minutes I think !

It isn't as bad as the 3/4 ton company ford truck I had with a 302 and a plugged cat !

[F-BIRD'88]

The tuned length of the lq4 intake system is not long enough to give a torque boost at the low rpm range you want. A cam won't change that.
A cam that is bigger than stock will add power only at higher rpms. And make less power in the 2500-3000 rpm point.
High performance hot rodded engines want to rev.

[racin69z]

Another thing I've been tossing around is using some 862 5.3 heads. About 20cc smaller runner and a smaller 1.89 intake valve. I thought if I did some minimal bowl work and kept the size down it would have better velocity at lower rpm. The heads have a way smaller chamber, but if I were to open the chamber at the valves to the 4" bore size that should increase chamber volume about right for my desired compression. I wouldnt think 9.75 or 10:1 would be too out of hand. Has anyone towed hard with an lq9 (10:1) while logging knock retard. I wouldnt be opposed to towing on higher octane but wouldnt want to be married to it every day.

Lynn

[PackardV8]

I do quite a bit of heavy towing and would really like a torque boost around 2500-3000 rpm. I am looking for a budget friendly cam.

Probably never gonna happen.
Improving the LS within the designed operating range is a very difficult task. We've all seen tests where the OEM intake outperformed all the aftermarket and the OEM cam outperformed the aftermarket. The key words here are "designed operating range." You specify 2500-3000. GM did sweat the details there already. More power at the very top end is easier to get, as GM knew few truck owners wants to spend time and money up there.

jack vines