For Those with Aftermarket Camshafts

[Foggy]

I did a dod delete cam this spring.. Retaining VVT. The specs are in my Signature.
I'm still learning and tweaking the HP Tuners to get it to behave at idle...
But my question is: Did your new cam make your exhaust a lot louder ????

My Yukon now sounds like a cammed up racecar... It's very choppy and very noticeably louder
than with the stock camshaft.. Seems a little weird to me that the noise level is so much higher.
I have the kooks headers and cats with the rest being the stock 3.5" 6.2 denali single exhaust

I do have a magnaflow exhaust that I purchased last year, but I'm afraid it would be way too loud now

 

[Geotrash]

Hmmm... in my understanding, an LSA of 113 is going to be hard to get to a smooth idle. My 3-bolt Cam Motion Stage 2 truck cam in my L94 engine is no louder than stock and idles *almost* as smooth as stock. Here are the specs:

212/220 duration @.050", .553"/.553” lift, 117 degree LSA + 5, 112 IC
Cam Motion Grind No. is XA212-325/220-325/117+5

 

[Foggy]

Hmmm... in my understanding, an LSA of 113 is going to be hard to get to a smooth idle. My 3-bolt Cam Motion Stage 2 truck cam in my L94 engine is no louder than stock and idles *almost* as smooth as stock. Here are the specs:

212/220 duration @.050", .553"/.553” lift, 117 degree LSA + 5, 112 IC
Cam Motion Grind No. is XA212-325/220-325/117+5

That must be the difference then... figured the 113*+8 would be a pretty mild cam. I'll go find
my actual cam card and find the IC* and report back

 

[swathdiver]

I'm still learning and tweaking the HP Tuners to get it to behave at idle...
But my question is: Did your new cam make your exhaust a lot louder ????

Did you post videos for us to listen to yet? LOL

113 is tight for an LS motor, makes for a choppy idle that most folks want to hear.

Other than that, how do you like that cam? Thinking about that one for the Sierra someday.

 

[Foggy]

According to cam card:
Intake Centerline is 105.0*
Exhaust Centerline 121.0*

So lobe sep is 113* with 8* of intake cam advance ground into it

 

[swathdiver]

I remember reading a post by a guy called Thunderstruck on the PerformanceTrucks forums and he was using HPTuners to make the idle sound choppy on his and mentioned that it could be used to smooth it out as well.

 

[Foggy]

I've been jacking around with the HPT for 2-3 weeks straight, trying to smooth out
my idle.. It runs pretty strong (i think).. But it's really rough/choppy under 1000 rpms.
I have to bring idle up to 800 for it to really idle OK..
Remember, I took off the EForce supercharger and installed this cam and put
the intake/etc all back to stock.. So it's def lost a little power... But i'm trying to
maximize fuel MPG, esp while towing.
I haven't towed yet with the cam install, so I don't MPG yet...
At interstate speeds on a long (1400 mile) trip 2 weeks ago, I averaged between
14.5-16.5 mpg.. which is down from bone stock from what I remember being
about 17-18 with DOD and about 17 with DOD disabled.

Maybe??? Just maybe I installed the cam 1 tooth off on the timing chain mark???

This cam is "supposed" to be the stage 1 truck cam for towing.. No headers or stall needed..
So I'm just a little confused why this thing is so lumpy

 

[swathdiver]

This cam is "supposed" to be the stage 1 truck cam for towing.. No headers or stall needed..
So I'm just a little confused why this thing is so lumpy

I texted briefly with a guy in Canada with that camshaft, he loves it and said it made good power. He said, "nice idle that you know is there but not crazy". He tweaked it with HP Tuners as well.

Maybe send Gwatney a video of it idling?

 

[Foggy]

I texted briefly with a guy in Canada with that camshaft, he loves it and said it made good power. He said, "nice idle that you know is there but not crazy". He tweaked it with HP Tuners as well.

Maybe send Gwatney a video of it idling?

I'll give gwatney a call for sure... Yeah it's very different idle so maybe it's just the tune
I've been on the HPT forums and such and gotten it better than the crappy tune I paid $$ for,
but not nearly where I thought it would be... Thanks for the suggestions

 

[Foggy]

Did you post videos for us to listen to yet? LOL

113 is tight for an LS motor, makes for a choppy idle that most folks want to hear.

Other than that, how do you like that cam? Thinking about that one for the Sierra someday.

I suck at trying to post videos and pics... The one app that I used for this website went
to crap a while ago.. And my smart phone is old enough that it isn't smart anymore... Maybe
one of my kids can help me !!!

 

[Geotrash]

I suck at trying to post videos and pics... The one app that I used for this website went
to crap a while ago.. And my smart phone is old enough that it isn't smart anymore... Maybe
one of my kids can help me !!!

YouTube is what I use, then link it back here.

 

[swathdiver]

I suck at trying to post videos and pics... The one app that I used for this website went
to crap a while ago.. And my smart phone is old enough that it isn't smart anymore... Maybe
one of my kids can help me !!!

I'm in the same boat usually. I can post youtube videos from my phone but that's about it!

 

[strokersace]

@Foggy have you gotten your idle figured out?

My 6.2 block should be back from the machine shop next week, and I'm still needing to get parts ordered. I've decided that I'll stay with VVT given that I'm a 4spd trans with stock converter. My 1st choice is the same Gwatney cam you have, but I'd be running Blackbear tuning. I figure I'll put headers on as well, but leave my stock 3" exhaust for the time being.

 

[Foggy]

@Foggy have you gotten your idle figured out?

My 6.2 block should be back from the machine shop next week, and I'm still needing to get parts ordered. I've decided that I'll stay with VVT given that I'm a 4spd trans with stock converter. My 1st choice is the same Gwatney cam you have, but I'd be running Blackbear tuning. I figure I'll put headers on as well, but leave my stock 3" exhaust for the time being.

Yes... I did get my idle about 90% to where it should be.. I'm still fumbling my way thru HPTuners and learning as I go..
I think if I were to do it again I'd find a VVT cam that was just a bit smaller or at least have
a bit more lobe seperation- like 114 or 115 VS the 113 on the gwatney.
Now, if compression was higher than stock or displacement was a bit more it would be fine

 

[Foggy]

Just to Update: I went thru my "tuning school" book that I paid for and it really helped out.
Any cam larger than stock you have to turn the idle speed up to like 800 ish
and you have to add "base running minimum airflow" up about 20% to get it to run/idle.

I've really enjoyed being able to fine tune my 6L80E trans in regular mode and tow mode.
And modify the torque converter lock up parameter etc

I've got my MPG almost back up to stock. And my towing MPG almost to where
it was stock - about 9.5 mpg- 34' 9000 lb camper w 3 slides.
With the supercharger the best I got towing was 5.5-6 mph

Like I said, I'm still tweaking on this and learning
But I do know for sure that I've gained quite a bit of midrange power with the
camshaft change

 

[swathdiver]

But still no video so we can hear it! LOL