vct tuning

[02GTP]

anyone know if there is any power to be had with tuning the variable cam timing? when i shift from redline the car goes down to about 4k rpm so i dont really care how much power it makes before that but am far more concerned about top end power. id like to advance it a bit but want to hear from some others first, thanks.

2005 Mustnag Gt (manual)

[02GTP]

eric brooks, rwtd, anyone? lol

[RWTD]

RETARDING the cams up top can yield more power.

[mustangjonGT]

How would that be done with HP Tuners?

[RWTD]

A couple things:

1: I would work on the spark (timing) curves before I even attempted to do this.
2: Where do you live, what is your elevation, and what grade of fuel are you using?
3: Do you have the CMCV delete, or no?

Anyway, to answer your question in your post above, you will want to modify the Angle (IMRC Open) Torque and Angle (IMRC Open) Load tables.

[mustangjonGT]

South Texas
Elevation:95ft
Fuel: 93oct
I do have CMCV delete, and have taken your tuning info on adjusting for them from here: http://www.hptuners.com/forum/showpo...24&postcount=8

[RWTD]

Everything I am posting below above is pretty "standard" throughout the industry, so I do not feel that I'm giving my fellow tuners any injustice by posting up such basic information. It's also not "set in stone", and each tuner may find a better method or a more proper spark/fuel curve. Personally, I "calibrate" each vehicle in for that particular vehicle's needs, so not every similar vehicle I tune will have the same spark or fuel curves. Furthermore, all the "calibrator" skill level stuff is something each individual will have to learn like the rest of us professionals have done. I can't really teach one that over the internet, nor do I really think it's fair nor proper to do towards my fellow friends/tuners, and I think it's best that those who want to learn should consider taking an advanced training course, such as what Greg Banish offers.

Okay, on to you now...

Your factory spark curve is setup for 87 octane. To be honest, with the conditions you just posted, especially with the fact that you're running 93 octane, you can more than likely copy the MBT Spark table over to the BKT (Borderline Knock table), and possibly get away with it without knock retard. Since you've done the CMCV delete, you've already zeroed out the IMRC Spark Base and Base MBT tables, per my directions you linked to. So, copy/paste from the MBT to the BKT. However, on the BKT, I would pull out 1 degree from the 0.80 Load line, and 2 degrees from the 0.90 Load line. Therefore, your BKT should look like this:

32.400	37.000	40.700	46.700	51.000	51.400	48.167	46.850	46.133	46.000	46.000
24.300	29.300	33.300	39.600	44.600	45.600	43.567	42.700	42.067	41.600	41.600
17.300	22.500	26.600	33.400	39.000	40.600	39.433	38.950	38.600	38.400	38.400
12.100	17.500	21.600	28.800	34.600	36.600	36.200	36.000	35.833	35.700	35.700
8.800	14.200	18.400	25.700	31.800	34.000	33.833	33.750	33.667	33.600	33.600
7.300	12.700	17.000	24.200	30.300	32.500	32.367	32.250	32.200	32.200	32.200
7.000	12.400	16.600	23.900	29.900	32.000	31.800	31.600	31.433	31.300	31.300
6.000	11.400	15.700	22.900	28.900	31.100	30.667	30.350	30.133	30.000	30.000
5.000	10.400	14.700	21.900	27.900	30.100	29.667	29.350	29.133	29.000	29.000

(copy/paste if you need to)

This is a fairly common spark curve for 3Vs with 93 octane. Also, when doing this, you will want to ZERO out the Lambda Spark Correction table from 1.00 and lower (as in less than, such as 0.96, 0.92, etc. etc.), but leave the 1.15 and 1.30 ranges stock (those are there for a reason), and also zero out the IAT and ECT adder values that are below 100 and 200 degrees, respectively.

Furthermore, AFR needs to be no higher than 12.6 ACTUAL at WOT (flatlined across the board) on E0 (pure gas), so set your Fuel Base table to 0.8606557 (* 14.64 = 12.6 AFR) for any value that is 0.82 already (copy/paste "0.8606557" into your lambda value, highlight all the cells that say 0.82 already, and then hit "="). Use a wideband to verify that Commanded AFR = Actual AFR, and if not then correct the MAF transfer.

If you're running ethanol based fuel (such as E10), unfortuantely HPT does not yet have the Stoich scalar so you can easily change over to the stoich of the fuel you're using. Therefore, you'll just have to "cheat", and instead of using 0.8606557 in the Fuel Base table, use 0.8289102. This will make WOT AFR approx. 12.13x, which is safe for E10. Your fuel trims will correct for any discrepancies at part throttle.

Also, make sure that your Open Loop Delay table is zeroed out, and that your OL Delay Ramp is set to 0.1, and your OL Delay Blend Ramp is set to 0.50 (leave OL Delay Maximum set to 20). This will ensure that the pcm will immediately switch over to the Fuel Base table when you go WOT (or beyond the TP required for OL), instead of delaying and ramping, which can help reduce tip-in detonation chances.

Unfortunately, you won't be able to log for knock with HPT yet, but at least you do have the knock sensors that are there to help protect you. P.s. I don't personally do this, tho some do, but if you change the "Knock Mode" switch from "Global" to "Per Cyl", this will make the knock sensors work "individually" for each cylinder (only pulling out spark from the specific cylinder it hears knock on), instead of "globally" (pulling out the exact same spark from every cylinder, if knock is detected). Do NOT do this on 5.4 vehicles (i.e. the trucks), as the harmonics and deck height of the block will not allow for a stable reading of cylinder #2.

Regards,

James

[mustangjonGT]

Thanks for the info. Its good that we have some tuning support for the HPT Fords.

[mustangjonGT]

Anyway, to answer your question in your post above, you will want to modify the Angle (IMRC Open) Torque and Angle (IMRC Open) Load tables.

So what would be good numbers to use in these tables for the timing curve used above?

[lito]

Work the lowest two-three rows of the table from 3xxx up in a curve fashion till you get something around 15-18 degrees at 6500, I have not tested this specific area in deep enough to say what is the absolute best retard value but around that is usually where everybody works on a bolt-ons NA setup.

[02GTP]

wow thats a lot of info. eric brooks told me to change the cells that have the number 9 in them in the vct tables to 11 and that might help out up top. does this seem right? i do have the delete plates, in wisconsin and maybe a couple hundred feet elevation. i got my spark curve down pretty good, holds bout 29* WOT and a/f is a solid 12.7-12.8 to one. any changes i should make?

[02GTP]

i heard the 3V's like 12.8 AFR but you are saying 12.6 is optimal? also ive heard conflicting numbers but how much timing do the 3v's like with 93 octane? i run 29 now and never had KR. ive accidentally had it like 30-33 for a few runs and it never had KR. i dont have a dyno near by to check what makes the most power but what have you seen, thanks again.

[RWTD]

Some 3V setups at WOT can tolerate 28 degrees in the peak rpms, and others are fine up to 30 and 31. The problem is that there is the potential for KR at the higher levels, obviously, which can hurt performance when it happens.

What Eric told you about the retard is a safe conservative value to potentially pick up power. However, ONLY having a load-bearing dyno can tell you if you're moving in the right direction, so BEFORE you start raising much past stock, I would defintely get on a load-bearing dyno, such as a Dynojet 224xLC.

Personally, in my testing, I have not seen any difference between 12.6 and 12.8 AFR in power (nothing meaningful whatsoever), so why not err on the side of safety? The ole "newb GM tuning" mentality does not apply to Fords, althought there's plenty of that from wannabe pros (I'm referring to the shops).

[02GTP]

so INCREASING the number in the vct tables retards timing? cause i dont know what the "units" are on that table. im just trying to get everything out of my car i can. and mine can do 30*, ive done it before and have never seen KR. just wondering if its still making more power going to 30*.

[lito]

so INCREASING the number in the vct tables retards timing? cause i dont know what the "units" are on that table. im just trying to get everything out of my car i can. and mine can do 30*, ive done it before and have never seen KR. just wondering if its still making more power going to 30*.

No, the numbers in the VCT tables are degrees of retard OF THE CAM (if we are talkin about the same tables, angle IMRCopen/closed load/torque), the timing goes in the borderline knock table and the MBT is a clip for it, you could try 30* but the problem is that you can not datalog knock spark retard so you wouldn't know if you are getting knock or not.

[02GTP]

i have just watched the scanner for KR and have never had any, even with 30* of spark advance. but i run 28-29 so im safe there. the vct is the only thing left for me really. like i said, my spark advance is right where i want it as well as my AF ratio. would u go more than 11* in the vct tables above 5500rpm? and would u do anything with the numbers prior to those? (like where it says 3.5)

[lito]

i have just watched the scanner for KR and have never had any, even with 30* of spark advance. but i run 28-29 so im safe there. the vct is the only thing left for me really. like i said, my spark advance is right where i want it as well as my AF ratio. would u go more than 11* in the vct tables above 5500rpm? and would u do anything with the numbers prior to those? (like where it says 3.5)

When you say "have just watched the scanner for KR and have never had any" are you sure what you are watching is actually working? I say this because it is of my understanding (that could be wrong, as usual ) that the HPT scanner can only log the sensor activity and not the actually retard applied, if any. (I must say that I could never make the scanner work on my car, the only Ford I've ever tried with HPT, I do fords with another software), so you may not see anything because there is no activity there?

Regarding the cam retard, there is nothing better than testing, in this case you won't damage anything by testing lets say 14 in the last three rows of the last column (there is load in one of the axis and up top in the rpm range you load goes down) and up the ones at the left a little to up to the 3-4 columns of that same rows and see what you, if you actually feel anything. (I'm the worst seat of the pants feeler of the world, that is why I bought a load dyno )

[02GTP]

well i just tuned my buddies GTO yesterday and for some reason he had a few degrees of KR. the KR pid just went red and showed whatever number it was at the time. so for his car it works fine, but i have never seen it with my car. so your saying 11* is not enough, do a little bit more? what would u change the 4500 and 5000 rows that read 2.5*&3.5* respectively.

[lito]

well i just tuned my buddies GTO yesterday and for some reason he had a few degrees of KR. the KR pid just went red and showed whatever number it was at the time. so for his car it works fine, but i have never seen it with my car. so your saying 11* is not enough, do a little bit more? what would u change the 4500 and 5000 rows that read 2.5*&3.5* respectively.

Datalogging GM and Ford are two completely different animals, if it worked on a GTO it does not mean it would work in a Ford.

Try these values on your right bottom of your table:

7.000	7.580	7.510	10.000 15.000
2.500	4.000	5.000	11.500 15.000
2.500	4.000	5.000	11.500 15.000

[02GTP]

i wasnt sure but i know it works for one car lol. and those numbers seem to make more power up top in your experience?