58mm bbk made my car very touchy on the throttle.
08-04-2007, 08:35 PM
#1
58mm bbk made my car very touchy on the throttle. I have a BBk 58mm and slotted the tps so its in spec but the car literally leaps when you touch the gas. I have 3.42 gears and 2800 stall but its a pain to drive. I am thinking to go down to a 52mm stock or mabye 54 mm stock ported as don't think stock ported ones would be this jumpy.
I do have tunercat/jet program but have not used it yet. Is there some way I can make the car not so jumpy so always have to try to feather the throttle? Either with tuning or something. I am planning on installing my 305 cam and 1.6 rockers and mac headers with some le2 heads but dont want the problem to get even worse. I didn't port out my intake to 58 mm yet either .was going to do that when installing all the other mods.
I did have a 52 mm bbk on there briefly and don't think it had the jumpy throttle problem.
This car is technically the wifes car and she does't like it being so touchy on the throttle.If tuning can help this then appreciate any tips in that area.
I do have tunercat/jet program but have not used it yet. Is there some way I can make the car not so jumpy so always have to try to feather the throttle? Either with tuning or something. I am planning on installing my 305 cam and 1.6 rockers and mac headers with some le2 heads but dont want the problem to get even worse. I didn't port out my intake to 58 mm yet either .was going to do that when installing all the other mods.
I did have a 52 mm bbk on there briefly and don't think it had the jumpy throttle problem.
This car is technically the wifes car and she does't like it being so touchy on the throttle.If tuning can help this then appreciate any tips in that area.
08-04-2007, 09:08 PM
#2
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Doesn't sound to me like it has anything to do with the size of the throttle body. Have you verified that the TPS is showing 0% when the blades are in fact closed? Do you need to back off the idle screw?
08-04-2007, 10:28 PM
#4
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I guess I went about that the wrong way. If the idle screw were out too far then it would be pushing the blades open. However, I guess if the idle screw were out too far, it would be idling high (duh on my part).
08-04-2007, 10:37 PM
#5
Originally Posted by dhdenney
Doesn't sound to me like it has anything to do with the size of the throttle body. Have you verified that the TPS is showing 0% when the blades are in fact closed? Do you need to back off the idle screw?
08-04-2007, 11:26 PM
#6
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It is going to act totally different once you get the cam, heads, and intake ported. If you dont like it that bad, put the stocker back on until the other mods. You are probably hurting yourself anyway with not having the intake ported. Now you have a big lip that the air hits before entering the intake.
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08-05-2007, 11:23 AM
#8
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Originally Posted by speed_demon24
It has everything to do with the throttle body, at the same throttle % the bigger throttle body is letting in more air.
08-05-2007, 12:32 PM
#9
I think he is just not used to the "tow-in" of a 58mm tb, and he is saying it has too much reaction.
Once the blades open the slightest bit, it is letting in much more air then the stocker. I like the touchy responsiveness myself.
Once the blades open the slightest bit, it is letting in much more air then the stocker. I like the touchy responsiveness myself.
08-05-2007, 12:57 PM
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Originally Posted by Puck
I think he is just not used to the "tow-in" of a 58mm tb, and he is saying it has too much reaction.
Once the blades open the slightest bit, it is letting in much more air then the stocker. I like the touchy responsiveness myself.
Once the blades open the slightest bit, it is letting in much more air then the stocker. I like the touchy responsiveness myself.
08-05-2007, 03:26 PM
#12
Well tuning might be your problem. You have to tune the a4 for a larger tb (especially the 58mm!!). The reason is that the computer uses tps for a lot of parameters, but with a larger tb a given tps % represents a different amount of induction. So it will screw things up unless it is fixed for that. However usually without tuning it the shifts will just be really soft and slack, I don't think it would do what you are describing. could be wrong though. I mean it will obviously have a quicker throttle response, since less tps is required to get the same induction, but im not sure if that's all you are experiencing.
Last edited by infinitebird; 08-05-2007 at 04:07 PM.
08-05-2007, 11:08 PM
#16
Originally Posted by MY99TAWS6
Well fine so what do I need to tune then? I have tunercat/jet software for obd2.
You also want to verify the IAC counts, idle rpm, and closed tps % on a scanner and then adjust the blades accordingly to get good values there.
Also I would reduce the % tps to enable WOT parameter because otherwise your engine will be under a greater than optimal load before entering PE mode.
08-07-2007, 08:36 AM
#18
do LT1s have a restrictor plate? thats probably not the correct terminology, but what im talking about is a lip on the TB blade that is designed to desensitize the feeling of the throttle. My truck has one and ive thought about grinding it off the blade. Aftermarket TBs eliminate this 99% of the time, cause then you can "really feel a difference!" 
