I have a ls6 cam in the 5.3 I just built for my truck, my question is should I scrap the cam or try it out? Motor is a fresh 5.3 with mildly ported 862 heads (2" intake valves, ls6 springs, nice valve job, rocker hump removed, some bowl and short turn work) The engine is already together and ready to go in and the ecu has a tune for the ls6 cam. The truck is a 1989 sbsc silverado 3.73 gears, 4l60e, and Circle D 2800 stall. I have heard so many people say this cam is great in a 5.3 and many other say it is junk. Just trying to make a decision before the motor is in the truck.

 

There is some good information in this thread that could help you with your decision, page 3 is a bit messy though.

 

I put an LS6 cam in a 5.3L, and don't really like it. That said, it is stock 706 heads, stock truck manifolds, 3.73 gearing, and a very heavy 4x4 suburban. With yours set up the way it is, it might be a good match.

I still think you won't feel a lot of low end torque, which may affect how good it works in your truck, but with a 2800 stall, you might do better than I did.

As far along as you are, try it out. I mean, it's already built and tuned. Don't be surprised if it doesn't deliver as well as you expected or hoped. Personally, I think that cam would be much better if the LSA was tighter. Would have helped with torque, and the overlap would help with power.

 

Changing the cam while its in the truck is pretty easy, so I wouldn't let that stop me from installing it

 

Yank it and put the LQ9 6.0 cam in or a Crane 200/200.

The LQ9 6.0 cam (same one used in the late LS1's) gives up only -8lbs of torque down low(2500rpm) and still makes + 40 hp @ 6500 rpm.

The Crane 200/200 gives up no torque @ 2500 rpm and makes + 40 hp up top. Also note it makes +15 lbs more torque in the mid range.

The LS6 is down -20ft lbs @ 2500 rpm and makes +90 hp up top.

The LS2 & LS3 cam have much better power under the curve then the LS6 but still give up a good bit of TQ down low.

In a daily driven truck, low end TQ is the last thing you want to give up imo.


Here is a good read.

http://www.hotrod.com/how-to/engine/...st-comparison/

 

Wr

I have read tha thread and article in car craft a few times. I think there is misprint in the article because they never listed the correct ls6 cam specs.

 

I wouldn't try to use an LS6 cam with heavier solid valves and the extra rpm a 5.3l will need vs a 5.7.

 

Like I said, I don't like it in mine. I've not changed it, because I'd rather dump money into the trans am than the suburban. I still say since you've already got it in and tuned for it, you can give it a shot. If you're trying to avoid changing the cam while its in the truck, you'd do far better to get a drop in cam from cam motion. They do quite well at developing torque and power with moderate lift.

The bottom line is that the valve events were chosen for a 5.7L going into a very light corvette that is expected to rev. A 6,000 pound truck witha 5.3 will not behave the same.

 

Darth_V8r your right, I'm gonna try it and see how it works. If I don't like it I'll pick up something different. Heck it has to be 100% better than my 300k mile tbi 350 regardless.

 

and if you find, like Darth_V8r, that you don't like it; there is always a market for a LS6 cam here. Sell it and recover some of the money.
I have the LS6 cam in my car. m6 and 4.10 gear, 2800 lbs

 

Pull the LS6 cam and sell it!
With that 2800 stall TC I'd go with a bigger cam (up to a 216/220 114lsa).
Imo, the BTR Truck Stage II Camshaft (212/218 113lsa+2, lift is .553"/.553") would be a good option, and can be safely used with LS6 valve springs., and would work good with your 2800 stall TC..

 

Well I have been driving my truck with the swap for about a week. I finally decided to just give the ls6 cam a shot. I'm actually pretty pleased with it, although I don't really have much to compare it to. It seem to like the converter and 3.73 gear in the truck. The BlackBear tune is great, fires right up, idles well, and the trans shifts firmer. Truck averaged 22mpg on the first tank with me keeping my foot out of it most of the time. The only thing I need to do is go back and check the preload on the lifters/rockers, I have a very slight tick I would like to get rid of.

 

Glad it worked out for you. i'm trying to understand why your results are so different from mine:

1. Stock 706 heads vs ported 862?
2. Stock converter vs 2800 stall?
3. Is there something lacking in my tune?
4. 4WD vs 2WD parasitic losses?
5. Weight of suburban vs smallest lightest Silverado?

 

I am preparing this new crate engine to swap into my 2004 Silverado w/ a 4.8L. I will delete the AFM function and lifters before the swap. Can someone recommend the best GM cam for low end torque? I read the hotrod test:
http://www.hotrod.com/how-to/engine/..._plusone_share.

and have concluded that these are the best cams for low end torque:

1. gm part #12561721 196/207, max lift 0.479/0.467, LSA 116 2. gm part #12560967 191/190, max lift 0.466/0.457, LSA 114

The #2 above is the cam in my 2004 4.8L, I think it will give the most torque. but maybe #1 is best.

My old engine: 2004 LR4 4.8L, w/head casting 12561706 and 1.98" inlet valves My new engine: 2009 LY5 5.3L, w/head casting 799 and 2.00" inlet valves

my new 5.3L LY5 AFM cam is part #12563207(also part #12625436), I have removed it from the 2009 5.3L LY5 and have measured max lift @ 0.480/0.480. Can I use this cam if I remove the AFM function? The other specs are nut published by GM. Maybe this is the best cam for low end torque.
Any advice would be appreciated. GM has sent me the detailed drawing for this cam but I cannot interpret the duration from the drawing. The drawing is attached.

Thanks, Charlie

 

Darth_V8r, I bet the lower weight and higher stall TC helped him a lot. If you have no plans on swapping in a better cam in the near future you should consider getting a Cloyes adjustable timing gear set and advancing the cam 6*- 8*. that would lower the IVC from 42, down to 34-36, which will raise the DCR around 1/2 a point, and shift the power band down 450-600 rpm. Doing that should make for a noticeable improvement in useable power below 5k rpm. Keep in mid that The LS6 cam(204/218) has 2.5* retard ground into it, that's why I recommend advancing it 6-8*.

Cloyes, Hex-A-Just #9-3158A, (adjustment on cam gear) $160 at Summit Racing.

or

Cloyes, Race Billet #9-3658TX9, (adjustment on crank gear) $150 at Summit Racing.

 

Thank you! that sounds like very good advice. I didn't realize the cam had any retard ground into it. I would never have got it if I did. Live and Learn

 

Thanks for posting that bit of info , that's want I've been looking for , does anyone else make a adjustable timing set ?

 

So 204/218 116-2.5 ; is this the one with .525 lift or .550 lift ? Do you have specs on the other LS6 cam ? I'm trying to figure out which one I have.

 

https://ls1tech.com/forums/generatio...ml#post4044886