New cam in my c7 where to start in the tuning process first

[Redline MS]

I'm not in the business, but while I agree with you that some kind of certification would better serve customers, it would not eliminate possible attitude problem... i.e. a shop or tuner who would profit from the cert, yet still put out snerf tunes.

I hear where you're coming from, in that there seem to be a ton of under qualified people preying on the uninformed.

I wish you the best in keeping ahead of the whack pack, in that you seem to love this stuff and passion is part of what is needed.

steps down from 6" pedestal...

I have been trying for years to put a calibrators association together. A group of guys that are at the commercial workshop level who handle volume and are exposed to a wide variety. It would be a way for customers to better decide who they want finger blasting there controller. I commend the guy with a single licence that makes hard attempts to figure it out but when your going from a E38 to a E92 and then having to dig deep in your brain for an LS1 in one day....you start acquiring a lot of diversified experience. We have been fortunate enough to get new GM products early to start reverse engineering what is going on but as I have said numerous times if you didn't pay attention in 9th grade that 12th is going to be more of a struggle. HPT is in business to sell software and does a great job as does the guys at EFIL, but its also liking putting a gun in the hands of a child. There used to be a time when if you could bench 500 lbs you were immortal....now a $800 HPT cable and a $400 laptop and you can walk on water.

The good guys out there that can calibrate struggle plenty...believe me...it happens when you push for more results....leave the attitude aside and you can have a great network of friends in this industry... but every one has THERE "tuner" so its just how the game works.....the smart customers know where the results come out....and its not about a dyno sheet... its about reality.

Just think....in 4-5 more years its gonna start all over again...new controllers new technologies....strap in boys its gonna really separate the packs!

[LSxpwrdZ]

Soooo.... how well are you guys prepared to map the speed density model? Are you locking the cam at zero and treating it like a GENIV or are you taking multiple layers of GMVE data at various cam angles and using a regression tool (that isn't part of the HPT suite) to solve for the cam angle coefficients?

I lock the cam at incremented angles to first see power output vs cam angle at various RPM breakpoints and correct for the VE using the variable cam section of Bluecats tool. The built in VVE tool is broken for VVT sections. The GenV makes this a bit easier with on the fly cam changes within the VCM controls. Also back calculating a GMVE error based on dynamic airflow (when locked into MAF only) and lambda error to correct the VVE at the same time I'm calibrating the MAF sensor.

[GHuggins]

I have been trying for years to put a calibrators association together. A group of guys that are at the commercial workshop level who handle volume and are exposed to a wide variety. It would be a way for customers to better decide who they want finger blasting there controller. I commend the guy with a single licence that makes hard attempts to figure it out but when your going from a E38 to a E92 and then having to dig deep in your brain for an LS1 in one day....you start acquiring a lot of diversified experience. We have been fortunate enough to get new GM products early to start reverse engineering what is going on but as I have said numerous times if you didn't pay attention in 9th grade that 12th is going to be more of a struggle. HPT is in business to sell software and does a great job as does the guys at EFIL, but its also liking putting a gun in the hands of a child. There used to be a time when if you could bench 500 lbs you were immortal....now a $800 HPT cable and a $400 laptop and you can walk on water.

The good guys out there that can calibrate struggle plenty...believe me...it happens when you push for more results....leave the attitude aside and you can have a great network of friends in this industry... but every one has THERE "tuner" so its just how the game works.....the smart customers know where the results come out....and its not about a dyno sheet... its about reality.

Just think....in 4-5 more years its gonna start all over again...new controllers new technologies....strap in boys its gonna really separate the packs!

This is what I try to focus the majority of my tuning on - drivability and "reality" and I've spent many a day banging my head against the wall trying to figure something out I just had one hauled here from Hennessey in Texas to NC even though the owner lives in FL (has a summer home here where he drives it regularly), because apparently they couldn't figure out what was mechanically going on with this particular customers vehicle... So far looks like the majority of his problem is now fixed... Now that I said that - it'll come back

I think everyone tuning a gen 5 or newer platform needs to bring one of their "tuned" suv's that's had a blower added up here to the mountains and drive it - This thing is the only one I've driven that will make you sea sick Constant throttle / pulling a steap inclimb - surges like the dickens and increases in rpms and vehicle speed with every surge without changing the throttle... Runs nice and smooth at 1200 or less elevation - anything above this and it's junk...

Oh well, my ranting for the day

[rjw]

anyone else gonna help the op? or

[GHuggins]

OP hasn't posted anymore on this since last November - None of us know if he's still having trouble or not? I guess it's just been post on the importance of not doing hack jobs and getting the air models dialed in correctly since then...

If the OP is reading this - are you still having issues that need assistance?

[rjw]

OP hasn't posted anymore on this since last November - None of us know if he's still having trouble or not? I guess it's just been post on the importance of not doing hack jobs and getting the air models dialed in correctly since then...

If the OP is reading this - are you still having issues that need assistance?

I was joking....I imagine that he either got it taken care of, or who knows??

[rjw]

maybe on a ford it would be more complicated, which is why everyone only tunes the MAF.....

on my personal GM with VVT, the cam angle retards but is the same at any given load/rpm whether WOT or part throttle.....

for example, it is fully advanced with 0 up to, say, 4000 RPM, across the board, then retards to, say, 3 by 7000 RPM.

there is no retard for EGR at part throttle.
the VVT spark tables are zero'd.

the VVE table is tuned and the MAF is tuned and the spark tables are tuned.

my LTFT are disabled, my STFT are -3 to -5% everywhere all the time.

416ci with blower.....runs good. very smooth, no hiccups.

what tables are you adjusting for that cam advance/retard....I think that I got it, but want to be sure

cam position for low, med, high baro? also, what is full advance/retard? with oem phaser -30 to +30...with restricted travel phaser, -11 to +11 ?????

thx

[Higgs Boson]

what tables are you adjusting for that cam advance/retard....I think that I got it, but want to be sure

cam position for low, med, high baro? also, what is full advance/retard? with oem phaser -30 to +30...with restricted travel phaser, -11 to +11 ?????

thx

yes those tables plus the WOT table. 0 is full advance and any numbers in the cell are degrees of retard so a 10 would be 10 degrees retarded.

we can't advance any more than is ground into the cam, it's just the limitation of the GM system with OHV single cam.

I typically remove retard down low for more torque at part throttle and never retard more than stock. with an aftermarket cam you would want to do sweeps on the dyno to find the best retard curve for your setup if you have the time/money.

[rjw]

yes those tables plus the WOT table. 0 is full advance and any numbers in the cell are degrees of retard so a 10 would be 10 degrees retarded.

we can't advance any more than is ground into the cam, it's just the limitation of the GM system with OHV single cam.

I typically remove retard down low for more torque at part throttle and never retard more than stock. with an aftermarket cam you would want to do sweeps on the dyno to find the best retard curve for your setup if you have the time/money.

cool stuff...it's all as clear as mud ! just kidding

thanks again

[Asylumwarp]

On an aftermarket cam, is there any reason to retard it? Or can I just zero out all these tables? We already have the Cam selection set to NONE, I would think these tables are no longer used at that point?

I see the old tuner zero'd out all the tables beside the High/WOT tables, but still turned the setting to none.... Think their useless at none correct?

[rjw]

check HB's post above....0 is full advance....maybe give comp cams a call. that setup must also have a restricted phaser. log cam angle commanded and actual? must exist in the software.

[Higgs Boson]

if you have a VVT cam then you might as well use it for some retard. if you have deleted VVT then you can turn it off in the tune. otherwise, some cam grinders or spec'ers may have an ideal curve to start with or use or you just have to do some sweeps on the dyno to find where the transition from advance to retard and how much of each makes the most power. I will say, the cams I have used in the past only get 2-3 degrees of retard up top, nothing like a stock cam at 9.

[Proxses]

I've also noticed that most cams are not cut with much advance to take advantage of the phaser. But I've also found it's hard to get a cam company to cut more than 10 degrees, as the cores are rarely hardened for more, I believe.

[rjw]

some questions:

1) If 0 is full advance, and in a stock lt4, max retard is 9, can I assume that straight up (no advance or retard is around 4-5?)

2) Can I assume that the phaser restrictors used with comp cams is to avoid valves hitting pistons with higher lift cams

3) why does the oem phaser allow 60 degrees of adjustment?


thx

[Higgs Boson]

the last stock cams I saw degree'd were gen iv cams and they had 7 degrees of advance at value 0 so I wouldn't assume it's linear to a tune value. the part throttle values can get into the 20s or 30s on some stock applications.

[rjw]

the last stock cams I saw degree'd were gen iv cams and they had 7 degrees of advance at value 0 so I wouldn't assume it's linear to a tune value. the part throttle values can get into the 20s or 30s on some stock applications.

any link to oem lt4 cam specs?

in comparing oem 5.3l to lt4, the 5.3 holds 0 till around 4k (wot), while the lt4 tune starts retarding at 1000 rpm??

check this out...difference between LT4 low baro cam timing and oem 5.3L. the 5.3 is the compare file

what do you think? are the high values in the 5.3 tune ALL retard?

[tunerpro]

Just think....in 4-5 more years its gonna start all over again...new controllers new technologies....strap in boys its gonna really separate the packs!

Just wait. Over the next year, it's going to become much more difficult, in some cases impossible, sadly, thanks to car hackers (outside of what we are doing), "tunerz", EPA pressures, etc. It will be interesting indeed.

[Higgs Boson]

any link to oem lt4 cam specs?

in comparing oem 5.3l to lt4, the 5.3 holds 0 till around 4k (wot), while the lt4 tune starts retarding at 1000 rpm??

check this out...difference between LT4 low baro cam timing and oem 5.3L. the 5.3 is the compare file

what do you think? are the high values in the 5.3 tune ALL retard?

LT4 is boosted which means more cylinder pressure which means retard at low RPM will bleed some of that off to prevent knock

[rjw]

LT4 is boosted which means more cylinder pressure which means retard at low RPM will bleed some of that off to prevent knock

ok, that makes sense, thx

[2000_SS]

Soooo.... how well are you guys prepared to map the speed density model? Are you locking the cam at zero and treating it like a GENIV or are you taking multiple layers of GMVE data at various cam angles and using a regression tool (that isn't part of the HPT suite) to solve for the cam angle coefficients?

how is a guy like me supposed to learn this? or even know that it's something i need to learn? i've yet to encounter a genV vehicle but would REALLY like to be prepared for when i do. I don't own a dyno and i weld for a living, tuning is just what i do on the side for fun. I'm no software engineer or master with excel, so it concerns me when i consider the possibilities of what i have yet to learn and what i will find out that i need to learn.