Acceleration Delay

[Chris92]

before you flame me, i've tryied searching for someone who has already answered this but i can't find anything

problem is when i put my foot down there is a big delay between the time i put my foot down to the time the acceleration actualy kicks in, does anyone know how i can fix this?

cheers
chris

[matt-chops]

Define 'big delay'... are we talking not instant, as in momentary?... or like a couple of seconds?

Does it rev up then just take a moment to start accelerating? If your engine mounts are shagged the motor will be turning in the bay a bit before the acceleration kicks in... this happened to me in my SV6.

[Chris92]

more momentary, maybe like .5 of a second or 1 second

[matt-chops]

That's pretty much what mine was doing before the mounts were replaced. It revved up, then when engine/drive train caught up the power would come on with a bit of a thud.

Could be something entirely different though... I'm no expert, just speaking from experience.

[impulsive]

if it is an alloytec i have been led to believe its something to do with the FBW (fly by wire) setup, where the throttle is sent to the motor via a signal not a cable as such like most other cars. Usually a tune and diff gears will get it responding quicker!

[Chris92]

yes its an alloytec, okay so is this the only method to fix it do you no?, the tune and diff gears.

[tanner892]

Just sounds like a modern car with a homo fly by wire to me and an auto, although my sv6 is fairly responsive from standstill (not great) but obviously in standard driving with an auto u get a big lag on kickdown and the fbw doesnt help either :P, not sure if theres really a cure for this though just the way it is, but yeh maybe define "delay" how long r we talking exactly, 0.5-1 second is probly normal including the kickdown.

oh and another thing, ive got an eb falcon that uses a cable throttle and was wondering why in the world was it changed to FBW in modern cars? feels alot better to drive in my opinion, was it an attempt to create a smoother ride or something? anyone know?

[Chris92]

yeah the delay is like .05 - 1 second max, its just annoying because i put my foot down, and the power is delayed. So there is no fix for it?

[tanner892]

yeah if ur talking about INCLUDING the kickdown to lower gear id say thats normal, cause u got the delay with the throttle then it figures out what the hell u wanna do then its gotta change the gear so id say its normal, fixes, well there are shiftkits you can get, no idea what for the VZ though, b+m seems to be the general brand that i see used, so maybe research that if your really desperate about it, a lower diff ratio will probly help, but id say the delays still gonna be there.
Like just an example on ebay which i just randomly searched and found;

T700 4L60E B&M SHIFT IMPROVER Kit VR TO VZ commodore - eBay Other, Performance Parts, Car Parts, Accessories, Cars, Bikes, Boats. (end time 11-May-10 09:16:25 AEST)


but obviously look into it a bit more, but this is more of a thing if u really wanna get ur car goin fast for drags and such, not for an everyday driver in my opinion, spose it depends on how desperate you are about it, but there is no quick fix for this, its how they are.

[impulsive]

dont know how far ppl have gone with shift kits, i only know of the one that has been fitted, Manual 6 SPD FTW!!

[Chris92]

i completely understand that its not just a quick wip up job that can be fixed instantly thats fine, thanks for the help. im just wondering on differant way or a way to get rid of it if possible. I could be talking absolute crap but just wondering is it possible to change it to like cable throttle so that there is no delay?

[tanner892]

Well as far as i know the electronic throttle sends info to the ecu regarding pedal position, which will then control the electronic throttle body, so if you were to change to cable not only would i imagine this being a huge job, but you may have to change heaps of other crap aswell, ecus, throttle bodies, i have no idea what else, the ecu probly runs off the info sent by the fly by wire as a major part of operating the engine id imagine, so yeah, i dont THINK itd be possible
I spose a quickshift will improve kickdown, a lower ratio diff will give better acceleration, but as regards to throttle delay, nothing i know of, i feel your pain.

[Chris92]

yeah i had a feeling that job would be a bit to big, thanks for all the help anyway mate. I might go down to HP-F and see if they no any ways making it less noticable

cheers
Chris

[SV666]

Yeah i actually spoke to a guy a Watson Holden over where i am in regards to this problem as it happens to me as well. He explained that (correct me if I'm wrong was a while when he explained it so it might be a tad off) whilst driving say 60km and you hit an 80km zone, put your foot down and yes you get the rev up delay then power! its to do with the gearing something along the lines of how locks in and out of each other so it locks out while cruzing then when you want power and hit it, it takes that quick second to lock itself in (gears) then it does what it does. The sport gearing the SV6 has he went on to tell me that in normal drive mode it acts like sports shift mode when its under heavy acceleration (3k-5k revs) without shifting into sports or manual modes.

Yeah i hope that made some sort of sense also dont know if it will be much of help considering the different models figured i give some input.... Like i said it was a while ago when he explained it all but it's like this with every alloytec..

[Chris92]

ah ok thanks mate that makes it so much clearer, thanks a heap. so the sv6's wouldn't have this delay because the sports gearing is 'enabled' during cruising so that in that in the case of putting your foot down in between 60-80km it will act instantly and acceleration will be instant? correct me if im wrong

[SV666]

Sorry it does give me that 1 second delay because while cruzing the gears are not coupled in so to speak its only when you want to give it a squirt it will give you a delay then the gears lock back in thus gives you acceleration back then goes for broke. Sorry may have explained it wrong, only does this while you are just driving along from the lights isn't a problem like others had said short diff ratio, and or better shifter should overcome the problem if its annoying.

[Benboy]

If you are cruising at say (about) 90km/ph the auto trans has probably engaged overdrive. If you use a bit of anticipation and drive a little ahead of where you are (if you get my drift) then you can manually select 3rd gear and when you put the boot in the revs should immediately propel you forward at a fast rate. Great for overtaking - works for me. Nolag or delay whatsoever.

[Chris92]

yeah i've done that before benboy thanks for that, so ultimatly just suck it up and deal with it is the drift im getting? :P

[mattyr82]

would the "active torque management" be delaying it too on heavy accelaration, especially during takeoff if u floor it. cos my way of thinking it would take a split second for the sensors to compute with the ECU to say hey, this pr*&ks trying to do a wheely, lets stop him.lol i believe u can get that disabled by someone with an expensive scan-tool.

[Chris92]

wow really matty? no of anyone in melb that has this special tool? or where i can look for someone that does?

[Chris92]

can anyone tell me if what matty is saying would work in to cutting the delay out? and who i could go too to get it done?

[Rusty]

I dont think that you have a problem with your car. Stock 6 cylinders are normally slow to accelerate when you put the foot down