Outstanding Throttle Response write up...

[slicksilver]

Also, wouldnt the brush mod make my car idle higher?

 

[MikeVistaBlue06]

Well, I really don't even have any deadspot right now.

I just want the throttle repsonse to be even more neck-breaking

Doing this will not make your throttle response better; all it does is take out the deadspot.

Your tune is where you need to look at improving throttle response, and if you want neck snapping acceleration, then I suggest you look into a twin screw supercharger.

Hope this helps.

Mike

 

[Charlie Sheen]

...all it does is take out the deadspot....

And that's only if you had one to begin with.

 

[DusterRT]

I'll go ahead and bump this, because it worked great for me. I had at least 1/4" of dead movement, now everything's gravy...

 

[MountainMichael]

MountainMichaels take on the throttle set screw

Seeing that this thread comes back from the dead every couple of years, I thought some CPR was in order. It lives!

Seemed to me that MikeVistaBlue06 had a good idea with the set screw... hoping what I'm about to show ya' is what Mike had in mind with his diagram.

Maybe the pics will help some. My car is a supercharged 06. I know quite a few 05's and 06's reportedly don't have the problem, but this one had it in spades.

I drilled a small locator hole outside the lever housing just as something I could measure from. I wanted to be able to hit the hidden portion of the throttle lever in the middle of 3 ribs with the actual set screw. From where I located this, it would be better if the tapped hole were about 1/16" lower than I put it though it is perfectly serviceable where I put it.

I used 1/4" NF (28) bolt with the head cut off and made a set screw out of it with a screwdriver slot cut into it. This, as my backwater hardware store does not have any fine thread set screws. I wanted fine thread due to going into plastic... for fine adjustment and due to using loctite as the main means of keeping it from coming loose.

Some pics. I hope... first attempt from a s197 n00b on pics... bear with me here...

In this first pic, the red line points to the small reference hole I drilled so I'd have something to measure from. The blue line points to the tapped hole for the set screw. You can see I sanded that area down after drill and tap to make sure the plastic burrs didn't mess with later adjustments:

This next pic shows the tap in place. Note that I'd removed the pedal return spring to make some room, but removing the lever wasn't necessary.

This next picture shows the prepped set screw next to a ruler. This length worked perfectly.

This next photo shows the back of the lever assembly with the tap in place and a ruler for location. Please remember: I coulda' gone down about 1/16" and that would be perfection. That hole below the 2-9/16" mark on the ruler is the locator hole I'd drilled for measuring purposes.

And finally this picture here. Let's see... what the hell is this one about? OK, yeah this is the one with the set screw and lock nut in place. The red line once again points to the superfluous locator hole that was drilled by me and used for measurements only.

One tip that shoulda' been obvious to me. When I adjusted the set screw til rpm's just started to rise... tightening the jam nut (just snug; the threads are only in plastic!) pulled the set screw back a tad - and so a small amount of "The Dead Zone" had returned. I had to remove the assembly one more time, loosen the jam nut and tighten the set screw another 1/8 turn or so, then snug the jam nut once again.

So in the future, my set screw adjustment procedure would be: Adjust set screw with engine running until rpm's just start to rise. Give the set screw another 1/8 turn. Then gently snug the jam nut. And of course, a round of loctite on both parts just before hand!

By this time, the loctite on the set screw and the jam nut was starting to set and I have good confidence nothing is going to move.

I did the throttle pedal recal as covered a couple of times in this thread. Works great! No more 1/4" plus dead zone on the throttle pedal!

Thanks to all involved with the idea. Now maybe I'll shift less like a spaz. For me, the main problem beforehand caused by "The Dead Zone" was unnecessary driveline lash when shifting at low speed low power levels. It's possible the driveline lash was especially severe due to the blower?? I dunno on that as I haven't driven an n/a s197 yet.

Hopefully someone will bump this thread... in about say 2013..

MMike

 

[MountainMichael]

Come to think of it, as well as the loctite was holding on the fine threads, the jam nut is absolutely unnecessary. Next time I adjust the set screw (if ever), I'll trash the jam nut.

fwiw,

MMike