vaughan 88 911

Hi guys. I'm the original poster of this question. Why is ask if throttle
response was improved was due to the chip manufacturers claim "improved
throttle response". HP and torque are increased some, but I am trying
to find any real world experience to support the manufacturers' claim that
throttle response is improved. So far, no one has been able to support the
claim yet. (All due respect to chip makers). Thanks.

dougn

you can search "throttle response" for some interesting threads. i have been trying to figure out why my car has poor throttle response for some time.

i have a LW flywheel, headers, SW chip, and cone filter intake. my car puts out good power (250 RWHP on a dynojet 248 D) and ohterwise runs very well but it has lousy throttle response and always has had poor response even before all the mods.

i notice it has great response when the engine is dead cold. as soon as it starts to warm, the response starts to degrade....

so i conclude the poor response is due to too lean fueling right off idle. the warmer it is outside the more sluggish my response becomes

i hate this condition i would buy a MAF set-up in a heartbeat if it would cure this problem.

Hoosier_Daddy

christallon

I bought a Sreve Wong chip last year for my bone stock RSA. I noticed the improvement immediatley in "seat of the pants" dyno. Don't know if I'd say it was throttle response, but the improvement in the rev range especially in the 1st 3 gears was there. A definate improvement. I can't comment on any of the other chips.

Hope this helps.

Chris

garrett376

Vaughan, what kind of "throttle response" improvement are you looking for? Are you looking for an improvement in the time the engine revs up for when you press the gas before you engage first gear?

rotorheadcase

I'm guessing that what Vaughan means is that when you press the loud pedal down there is an instant and rapid response from the engine in revs. This translates into a faster response from the car in terms of acceleration.

I've fitted a couple of different chips (the present one being a Ruf chip) and neither gave me any real improvement in "throttle response". I think there is a noticeable improvement in power delivery in that it is more linear across the rev range but that's about it.

My whole interior has just gone into the trimmers for an overhaul (dash, seats carpets, console) and driving around with just a Recaro PP and nothing else was amazing. It felt like a different animal in terms of acceleration and handling. I'm a "Jenny Craig"convert! It made more difference than anything else I've done to the car in terms of the engine.

Neil

Christer

This is why I asked for a definition of throttle response.

What I understand by throttle response is how fast the engine reacts when in neutral - i.e. when you blip the throttle. I can say that the standard card with DMF has really bad throttle response in this scenario - maybe not compared to a Opel Vectra but nontheless pretty bad. After I had my car modified, the throttle response was more like that of a motorbike - i.e. the revs rise and fall very very quickly compared to a standard car. I put it mainly down to the LWF, but having compared to other cars with LWF, they are pretty much as slow as a car with DMF. After some investigation, it seems that the Motec is the key component that is making such a difference to throttle response. Now don't ask exactly what it is, but it has to do with the sensors that Motec uses.

So thats my definition of throttle response - and is the only one worth talking about IMHO. Throttle response in gear - well if you have a turbo then I guess that might be something relevant - but how many 964's have a delay in response to throttle? If there is no delay in response from the engine to throttle input (which there shouldn't be) how does a chip improve that? I think throttle response is a phrase tuners use when trying to add another selling point to their products (at least in the case of chips/remaps) - maybe a MAF has the same effect as using Motec - i.e. the car's engine responds very quickly indeed to throttle in neutral. This of course makes the car a joy to rev-match and so on....

I have seen many a question from people who ask 'is there anything I can do to improve throttle response, for example to be quicker away from standing start'? And the answer is - well why does it matter? You have plenty of time in most situations where you need to get quickly away to dial in 4000rpm or whatever and sidestep the clutch....so why throttle response. In acceleration terms, only more power will make you accelerate more quickly, so why throttle response?

One last rant - on the BMW boards there are tuners that will offer to remap a 316i or whatever, and promise 11hp increase and 'increased throttle response'......does anyone know what this means in real life?

Lets keep this separate to the other chip/map/motec conversations about power and torque - lets concentrate on what 'THROTTLE RESPONSE' means to different people.....

Christer

IMHO, this is not throttle response improvement, if the car actually does accelerate faster then it is a power increase.....

Christer

please define 'throttle response'......this is the only way we are going to get anywhere....

Steven C.

My definition would be the motors ability to quickly get to a higher revolution. How quickly would be the amount of throttle response the motor can achieve.

In our race cars and my C2 we use a LWF to accomplish this. No increase in hp or torque but the motor can put the amount available to use sooner since the motor gets to a higher revolution sooner with less mass to spin. A chip can accomplish a similar effect if the hp and torque curves are moved lower in the rev band. The motor may not rev quicker but it will get to the "go" rpm faster.

This is the pick on the Honda S2000 motor as the available hp and torque is way up there making the car a dog around town. My Fiat is set up the same way with the cams we have in it and the usable rpm band is 7,500 to 8,200.The LWF in my Fiat is just an attempt to help the motor get going...or increase the throttle response up to this rpm band.

springer3

I see two things that affect perception of throttle response. One is lag time as the fluid stream in the inlet system is accelerated - turbo lag is an extreme example, but it is a factor in na engines as well. That is where any 911 shines because of the very short intake path. The second way to change perception is to recam the throttle linkage, so that it opens more in the first inch or two of accelerator pedal travel. At one time I owned two 300E, a 1986 and a 1988. The 88 always seemed to be a quicker car around town. Performance was actually identical when measured (sorry, acceleration rate again). I suspect the progression of the throttle was different between the two cars. Of course, you can know that and compensate by moving your foot a little more. Then the two cars seem just as quick.

Christer

So to me, what you are describing is that an S2000 lacks torque low down in the rev range, which is nothing to do with the throttle response, this is a power curve issue. 'Getting to a higher revolution sooner' if the engine is under load (in gear) can only be accomplished by in effect having more power, again nothing to do with throttle response whatsoever.

Steven C.

Correct, but one can mimic the other....to some extent.

springer3

The confusion is over the meaning of response. To me it is the behavior of the engine in response to a step change in throttle position - idle to WOT being the most extreme case, but flooring it from any setting is also important from the driver's perception.

The issue is the time it takes for the engine to transition to steady state after the throttle change (ramp rate). Carburetors had throttle pumps to keep the engine from bogging due to over-lean conditon when the pedal is pushed down fast. Injected and computer controlled engines can also bogg due to temporary over-lean conditions, particularly if worn parts or improper modifications are involved.

The steady power the engine makes is a separate issue, and one that makes a big impression on driver perception. "Response" is also a perception issue, so think of it any way you want.

vaughan 88 911

Hi guys. I'm the original poster. Sorry for my delay.
What I meant was 'how quickly the engine responds to depressing the accellerator pedal'. Moreso I'm speaking off the line, going from 1k to 5k rpms. I believe what I notice is the DMF. There seems to be a bit of a lag before the flywheel gets up there. I wondered if a chip could be mapped to quicken the response time from pressing the accelerator to getting the revs up.
Seemingly a LWF would help, but could a chip (alone) help?
This is why I posted the question. Thanks guys. Vaughan