hands down more time should be spent on driveability, and proper WOT operation is totally reliant on proper part throttle/low speed calibration. I agree with eric. i'm confident I could teach a monkey to tune WOT in an afternoon. but I've seen some pretty intelligent people struggle with even the most basic concepts of driveability for an obscene amount of time. one should always be wary of the 2 hour tooner. that said, yes. your cam isn't that crazy. it should drive almost like a Honda......
Steck and Eric nailed it.... driveability is everything. Hell, we spend 99.9% of our time in cruise and at a stop light. If its shit there, its just plain shit, no two ways about it. I'm a freak when it comes to driveability, it has to be right and I will not stop until it is. That's why guys like Steck, Sound(S2H), Russ, 5litereater and EFI are freakin' awesome around here. Guys like them are worth their weight in bloody gold!
When you get your program, read everything you can find on your platform and mods from those guys
2000 Trans Am WS6
I'm not using DFCO with my cam....
its not needed...
he needs to revisit some of the tune to fix the bucking and surging...
again... I have no issues driving my cam....
seriously...drives like stock...with a big lope.
-Scott -
I would be psyched if it drove like a Honda. I chose this cam thinking it would a breeze to tune, if I knew I would have this much trouble I probably would have went more aggressive stick.Originally Posted by tommytuner
I definitely would not want my car to drive like a honda....Slow, and idles at like 2500 rpm because none of those guys know how to tune..LOL
-Scott -
Will DFCO cause the low rpm / light throttle bucking? Or have something to do with it?
90% of the customers that come to me have had a "tune" before and their gas mileage is crap, drives like hammered ass, bucks, stalls, but for some reason they seem to love the wot. imagine that. I spend more time on part throttle cals than anything else due to the fact your not in wot 100% of time you're driving the car. I understand how things work and can see why gm did things a certain way on various vehicles and can see where they need to be worked a bit for the individual and their driving styles. "it made 1200whp on the dyno" so? you can't come to a stop light without two footing it because it will die.
The most hated, make the most power.
93 Ranger. 5.3 D1X. 1069hp.
And this is where I am now. Crappy gas mileage, bucks and stalls! Got to love it. I would give up power in a minute to get this to run correctly. I love all of the threads that vendors claim about their GREAT DRIVABILITY cams. I understand everyone needs to make money and promote their business but at least be honest with yourselves and the customer for that matter. Lesson learned.90% of the customers that come to me have had a "tune" before and their gas mileage is crap, drives like hammered ass, bucks, stalls, but for some reason they seem to love the wot. imagine that. I spend more time on part throttle cals than anything else due to the fact your not in wot 100% of time you're driving the car. I understand how things work and can see why gm did things a certain way on various vehicles and can see where they need to be worked a bit for the individual and their driving styles. "it made 1200whp on the dyno" so? you can't come to a stop light without two footing it because it will die.
What are your exact cam specs, also need to the LSA and the ICL.
Russ Kemp
Comp cam. 223/239 .625/.610 114 LSL lobes
no...DFCO is only enabled at higher rpms as it comes down during Deceleration
then it shuts off and fueling continues as normal once it gets below a specified value in the tune.
Bucking/Surging is caused by several posibilities.
Fuel
Spark
Idle Airflow
Throttle follower
Throttle Cracker
-Scott -
Where in North Carolina?
Is thus an EXR cam?
With only 3* overlap @.050, there shouldn't be very much light throttle/low RPM surge. Ask your tuner to delay the EOIT by 50* by adding .555 to the Normal Injection Target vs ECT. But with such a small cam, I don't think I will help much. Is the tune open or closed loop? Any DTC's?
Russ Kemp
Scott,
I have been told by several "famous" tuners that my 245/255 113 LSA cam in my manual 2005 C6 (E40) cannot be completely tamed for the street. I would happily forward my tune and whatever logs you want with a header installed wide band for you to eliminate surging under various conditions as high as 2500 rpm.
The issue I have now with my tuner or (past tuner) is he claims this is how they do things and everything seems completely normal to him. To put in perspective he also told me that my driving style is why it stalls all the time.... Said I need to push in the clutch around 1500 rpm when coming to a stop. I drove race cars for 24 years and can adapt to most anything. This tune is not right bottom line. I'm a slight perfectionist so settling for an average driving car is not going to work for me. So I'm waiting for my HP Tune to come in the mail. This ought to be fun. To answer your question about DTC, I will have more info once I get the program up and running. Looking forward to getting good advise, as I'm sure I will need it.
when you get your Hptuners, make sure the dfco timing and Cfco timing have been edited.... normally put them around 15-30 degrees depending on the setup.... on some os's the timing can actually go negative, and with a cam the minute you put the clutch in the motor will stall.
Owner of Cunningham Motorsports
06 z06
2016 camaro
68 Camaro
2014 e63 amg
07 LBZ Duramax
That setup shouldn't have any surging around 2500rpm... especially on an E40.
The only setups that have a few quirks IMO are big stalled auto cars with junk throttle bodies (mechanical TB w/ IAC). Those setups will have you chasing your tail. I get in a lot of TREX cam'd LS1's that come in previously "tooned" and honestly they were hard to back up onto the dyno without flashing a basemap to them. They normally leave out of here cruising in 6th gear at 40mph 1100-1200rpm with no bucking.
Now you will get some ringers every once in a while that are just awnry. Most of them I notice have erratic RPM signals and I think that contributes alot to some idle issues and surging at low load and engine speeds. Cause? Sloppy timing chain, resonance at a certain rpm, heck I don't know but digging in and tweaking various tables can definitely minimize the issues.
James Short - [email protected]
Located in Central Kentucky
ShorTuning
2020 Camaro 2SS | BTR 230 | GPI CNC Heads | MSD Intake | Rotofab | 2" LT's | Flex Fuel | 638rwhp / 540rwtq
2002 Camaro | LSX 427 | CID LS7's | Twin GT5088's | Haltech Nexus R5 | RPM TH400
A new GM LS2 HD timing chain went in with the cam. But if you want to solidify your status as a super tuner, I shall happily send you the tune and whatever logs you desire.
when you have issues with a tune, you should always post it...
post the actual file you are using and we can take a look at it.
if you have some logs of it happening, that would be useful also..
we may ask you to data log it with other PID's in the table as well once we see what is happening.
-Scott -
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