[chas350]

Hey Im thinking about a cam swap for my 2005 6.0 2500HD
I was looking at the Comp 54-408-11 (XR259HR)
.206 I /.212 E @ .050 duration and lift .515-.522 with 112 lobe centerline.
I have stock manifolds (maybe Longtubes later) flowmaster muffler, Volant CAI and a Hypertech programer.
The truck has .411 gears, automatic trans, 285/75-16 tires.
I have a 9000lb travel trailer I tow for camping, which it tows decent. Except for 1st gear before the rpms get up some like when from a stop on a hill or something.
I want some more low end, but am told the "cathedral" intake track is made for mid to upper end power. So theirs not much I can do about low end (so Im told) but if I could get more mid and upper without hurting the low much, I want it for the fun factor

I would like to hear what some of you have done or would do.
Comps camquest shows this cam making the most torgue/HP in my engine, and whats funny, even the bigger cams dont seem to match it.
Not sure if I should be chosing the L91 heads or the stock LS1 heads in the software, or what CFM to choose for induction. I did guess the LS1 heads and 800 CFM for induction. Its their free software version available online from Comps website. I called their cam help line but the guy wasnt able to help me chose the correct heads and CFM. Or really help much. He said to call back the next day to talk with the LS guru.

Any info or opinions are welcome

[chas350]

bump please

[Hogg]

The GEn 3 heads arent hugely conducive to low rpm torque. the 4l80e with its 2.48:1 1st gear doesnt help getting the truck rolloing from stops either.

Have you looked into PCM tuning? Large torque/powergains can be had from your LQ4 6.0 engine. The stock tune is quite limiting.

Tuners

Westers Garage
http://westersgarage.eidnet.org/

Fastchip
http://www.fastchip.com/

Nelsons
http://www.nelsonperformance.com/


these guys are all reputable PCM tuners, and will offer power gains that might eclipse power gains of a cam swap.
EFI engines have whats called TM or Torque Management. This to protect the transmission from the engines power. From dead stops, heavy throttle and just before ALL upshifts the PCM (powertrain control module) momentarily reduces timing advance, therefore engine power. You have the 4l80e trans which is a particularily strong and robust trans. I suggest disbaling TM 100% in your truck. If you had a 4l60e truck I might only disable 80% of TM.

In my 1997 Vortec 350 truck, disabling TM helped acceleration quite a bit.

The cam you have specced for yourself will help your low-mid rpm torque/power out nicely, it will be a torque monster. Couple that with a proper PCM tune, you could see substantial torque gains.

Here is a 220º/220º .581"/.581" cam swap that along with PCM tuning, headers and exhaust added 100 rwhp to a 5.3L engine. Thats over 120 hp at the crank.
http://www.ls1truck.com/forums/front...in-budget.html

I am not suggesting you swap to the cam above, just the gains possible with the correct combo. I really like the cam you have mentioned.

Check out this thread for inspiration. The XR259HR cam is actually suggested. The Vinci Ultra torquecam with 210/218 .551/.551 .
http://www.vincihiperformance.com/CA...%20LS1%202.htm

Your truck allready has a dual 3" exhaust from the manifolds to the muffler where it goes into 1 larger tailpipe.
Dont spend money on exhaust, except for maybe longtube headers and an aftermarket muffler.

Here are some direct fit muffler for your HD truck with the dual 3" pipes.
http://www.flopro.com/FP2500oval.htm

I hope I didnt muddle you up too much. But I think the cam you picked will give you what you want, esp. with a PCM tune.

peace
Hog

[chas350]

Thanks Hog!
I do have a Flowmaster muffler on it now. dual 3 inlet, single 3.5 outlet. Sounds good. I think it is hard to improve on the pipes, like you sugested.
I would like a set of long tubes, but not lookin foward to the fab work, or the cost!
My flowmaster has been on since sept 05 and Im detecting a slight change in the sound lately, think its on its way out. Anything new I put on will be SS, so I dont have to replace it again.

Have you heard of wait4me performance tunes? His name is Jesse Bub, I think. He will do a PCM tune for 75 if memory serves me right, but that was a year ago. He was saying he could get me around 45-50 horses and equal torgue, again, if Im remembering correctly. My Hypertech is giving me 35 TQ and 33 HP i think, on 93 octane.
That comp cam must have a quick lift grind, camquest gives it good numbers for me.
Do you know what the 2005 6.0 has for heads?
Is this considered an LS2? or LS1? I thought the LS2 was Corvette......
I think, like you noted that it is a LQ4, but what LS#? Or head #?
Anyways thanks for the imput.
Im drooling with antisapation for power!
chas

[bradykat]

i would look at westers for pcm they can tune it to your needs
i have one in my sierra denali 6.0l and if it wasn't for the quadsteer and awd
i could really kick some *****!
it really woke it up

[Hogg]

Originally Posted by chas350

Thanks Hog!
I do have a Flowmaster muffler on it now. dual 3 inlet, single 3.5 outlet. Sounds good. I think it is hard to improve on the pipes, like you sugested.
I would like a set of long tubes, but not lookin foward to the fab work, or the cost!
My flowmaster has been on since sept 05 and Im detecting a slight change in the sound lately, think its on its way out. Anything new I put on will be SS, so I dont have to replace it again.

Have you heard of wait4me performance tunes? His name is Jesse Bub, I think. He will do a PCM tune for 75 if memory serves me right, but that was a year ago. He was saying he could get me around 45-50 horses and equal torgue, again, if Im remembering correctly. My Hypertech is giving me 35 TQ and 33 HP i think, on 93 octane.
That comp cam must have a quick lift grind, camquest gives it good numbers for me.
Do you know what the 2005 6.0 has for heads?
Is this considered an LS2? or LS1? I thought the LS2 was Corvette......
I think, like you noted that it is a LQ4, but what LS#? Or head #?
Anyways thanks for the imput.
Im drooling with antisapation for power!
chas

yes I have spoken with Jesse bubb as well, his prices cant be beaten.
I would take your Hypertech numbers with a grain of salt. The Hypertech doesnt do anything for TM disabling. You will for sure notice ANY good performance PCM tune in your truck.

Allen nelson netted over 400 crank hp ON AN ENGINE DYNO with just timing on a stock LQ4. Just remeber this is on an engine dyno. he didnt even touch the fueling. The HD trucks were detuned for federal Noise standards. The HD 6.0 have great results with PCM tuning.

You LQ4 is rated at 300-310hp, it has the same heads as the 345 LQ9 that is used the Silverado SS, Silverado VHO and Escalade engines. they are GEN 3 heads, and will bolt onto a 4.8, 5.3, and other 6.0's. Your engine is in the same family as the aluminum block LS1. the GEN 3 engine family is infact 4 engines, 4.8 LR4, 5.3 LM7/L99flexfuel/99-310hp all AL, 5.7 LS1(all Al), and 6.0 LQ4/9.
Your engine is an LG4, it is part of the GEN 3 family, also shared with the LS1. LS1 performance parts like cam will work on your truck.

LS2 is used in the 05+ Vette, SSR, Trailblazer SS, and GTO, this is a GEN IV engines. BAsically teh same architecture as teh GEN 3, except they use a 58x crank relctor and the knock and cam sensors are in different spots. Some GEN IV engines have DOD (displacement on demand).

With the cam, concentrate on torque as you have to overcome the longer 2.48;1 1st gear of the 4l80e trans. Lower lifts are also easier on the valvetrain.
here is your stock cam specs
6.0 LQ9
196/207 int/exh @ 0.05" duration
0.467/0.479"" int/exh lift
116 LSA
Also a STRONG higher stall torque converter will get your engine up into the power/torque band quicker. Since you tow, you wouldnt want to go too crazy.
the best are from Yank and Precision Industries. they are expensove, but are worth it. The PE TC's will support over 1000hp. They are lockup TC's which means that when cruiseing the TCC(torque converter clutch) locks and stock fuel economy and drivability is retained. Its basically like slipping a clutch in a manual trans. More tsall equals more heat, so an AUX. trans cooler will add extra cooling.

Precision Industries (Vigilante)
http://www.converter.com/

Yank
http://www.converter.cc/

Expensive, but worth it.

I hope I havent planted TOO mnay bugs. lol

peace
Hog

[chas350]

Hey Hog!
Diggin the info!

My cam choice doesnt add much duration. I know the lift will help also.
Do you think this cam grind would offer more under the curve and/or quick lift technology? It just doesnt seem to much bigger.
Can I trust the CamQuest numbers? I wish I knew of someone with this cam in their truck....

The Nelson tune sounds good, I read his customer testimonials. I sent Allen an email with a few questions.

I was a little confused about which engine I have, is it the LQ4, LQ9 or LG4?

I think I forgot to mention my truck is a crew cab, man is it heavy.

Chas

[RippinRon]

The LG4 is a Gen 1 305, The LQ4 (300hp) is the 6.0l that came out in 1999 and the LQ9 (345hp) is the H.O. 6.0l that came out in 2002 for the escalades.

[ap72]

If you really want some torque you're going to have to pony up about 4 G's for a supercharger. Its going to cost 4 times as much as your cam swap but for low end grunt on these engines its pretty much "the end all be all".

[Hogg]

Originally Posted by chas350

Hey Hog!
Diggin the info!

My cam choice doesnt add much duration. I know the lift will help also.
Do you think this cam grind would offer more under the curve and/or quick lift technology? It just doesnt seem to much bigger.
Can I trust the CamQuest numbers? I wish I knew of someone with this cam in their truck....

The Nelson tune sounds good, I read his customer testimonials. I sent Allen an email with a few questions.

I was a little confused about which engine I have, is it the LQ4, LQ9 or LG4?

I think I forgot to mention my truck is a crew cab, man is it heavy.

Chas

By looking at the duration #'s it doesnt look MUCH bigger, but the bigger the duration numbers, the higher the powerband, for the most part. Duration numbers arent the be all end all. Things like over lap and LSA are things that make a big difference as well as the other specs.
Allen Nelson can probably recommend a cam for you as well. If you go TOO big, you will be defeating the whole point of this exercise, which is adding to your low rpm torque.

Too large of a cam will decrease torque at the stock torque converters stall rpm, thus making off the line acceleration even worse. Remember the more torque you feed a torque converter, the higher it will stall. This is why I am using a 4,3V6 behind my Vortec 350 engine. My engine used to stall to about 1700 rpm with the stock 350 TC, now I can apply FULL brakes AND throttle and read 2700 rpm on the tach with the rear tires NOT spinning. Obviously I only hold this for a second or 2.
In all honesty, if you added a tune and a higher stall torque converter (about 2500-3000 rpm) your off idle acceleration would be remarkably different. I know this because you have stated that acceleration is not good until the truck is rolling and revs climb to about 3500rpm.

The problem with higher stalling torque converters is heat. The higher the stall, the higher the heat that is produced. An aftermarket trans cooler will solve this.
You have 1 of the strongest transmissions that GM has ever used, which is the only reason that I am suggesting 100% TM disabling.

I promise you that even with similar duration numbers, the cam you specced will offer more gains under the curve than the stock GM camshaft. Gm cams are designed to NOT stress the valvetrain and to offer maximum mileage.

here is the cam specs on the cam you are looking at

http://www.compcams.com/Cam_Specs/Ca...csid=1084&sb=2
You can also get a custom cam ground with the same specs, but with more lift if you wish. they are usually about $30 more than a normal off the shelf cam. You can always add a set of 1.85:1 rocker arms if you wish to up the lift, but I usually suggest that you do the work with the cam, and not the rockers.
You have an LQ4. However if you are finding that info is lacking, if it works on an LQ9 it will work on an LQ4.(there are some exceptions of course,the tune and the pistons are the only difference in 2005+) If you go into your glovebox and look at the RPO(Regular Production Order sticker, you will find the alphanumeric code LQ4. If you have the factory locking rear differential, you will find the code G80. Basically this sticker tells you what options your truck has.

The LQ4 from 99-00 used iron heads, the 01+ LQ4's aluminum heads. These heads are very similar to the 385-405 hp LS6 Vette heads.
The LQ4 is the only 6.0 that you can get in the HD trucks like your own. It was rated at 300-10hp and 360-370lb/ft of torque There was a 325 hp/370 l/ft version of the LQ4 that was used in the AWD C3 pickup and the Denali truck and the Denali SUV.

the LQ9 features less of a dish in the pistons thus the compression ratio is slightly higher. Allen Nelson states that taking the tune and exhaust out of the equation has the LQ9 only 5hp over the LQ4 based on compression differences alone.

Before you go whole hog here, may I suggest that you get a 93 octane pwerformance/towing tune that disables TM 100% and try it in you truck. I guarentee you that you will be impressed with it vs. the Hypertech you have now. Everytime you apply modest throttle to your truck, the PCM is pulling out timing advance, plus, since your truck has an electronic throttle, the PCM commands the throttle body to stay less open than it would with all torque management tables disabled.
If you likethe tune(you will) then you can do any mods you wish, and get Allen to do a retune.

I do agree with AP72, a positive displacement blower like the Magnacharger Radix kit or positive displacement compressor like the Kenne Bell or Whipple Industries kit will make that 6.0 act like an 8.1 on steroids. A supercharger and tune will allow you to retain a stock engine, and stock engine reliability.

Take care

peace
Hog

[chas350]

Thanks Everyone.
I have put everything on hold because my 21 yr old daughter was t-boned by a negligent 18 yr driver doing up to 80 to 100 mph (impact around 60-65) on a small state road with 40 mph limit.
The 18 yr female driver was late to her horse riding lesson. Multiple witness's she passed stated anywhere from 60 to 100 mph.
This happened last wed. She has a broken pelvis in 3 spots. Her shoulder blade is broke. Her left eye was cut (Thru eyebrow) about 2" long and very deep. Worst of all her diaphram was ruptured with part of her stomach and colon pushed thru. Much bruising also.
She is very lucky to be alive, their was a 24-30" intrusion impact at the drivers door. She just bought a new Hyundai with the side air bags....I think they saved her life.
If she was still driving her 97 tracer.......
I have been by her side eversince. Today I was able to come home for the night to get some sleep as she is improving and 1 to 11/2 hrs sleep a day has finally caught up to me big time. Please, say a prayer for her.
thanks guys
chas

[Hogg]

Good Lord. My prayers are with you and your family. Take care.

peace
Hog

[ap72]

I did a little over a month stint in the hospital about a year ago (motorcycle accident)- I don't wish that on anyone. My prayers are with her and all of her family- I know its taxing on them too.

One suggestion I have for when she can start eating nornmally is to bring her some good home made food and some old classic movies- it sound simple but that was always the highlight of an otherwise lonely and dreary day. Oh, and when you're up there see if you can borrow a wheelchair and take her out to see the sun for a little bit, even if its for five minutes. It gives her something to look forward to when she finally can be normal again.