Champion GN1 intake / TV cable issues

[D's GN]

I have a problem with the GN1 cast intake and the TV valve cable loosening its adjustment when the throttle is 100% open. Up to now I have only tuned part/mid throttle with the XFI and noticed the TPS was only at 82% on a wide open logging run. The transmission is shifting great at these points but when I manually pulled the throttle bracket to 100% the TV cable pulls out of adjusment. The shifts went soft instantly and luckily I noticed just pulling away from a stop slowly and did not cause any damage.

I reset it to the previous adjustment and it shifts great but I can not go WOT. Anybody come across this before? The cable is a new re-pro from Lonnie but I don' t think it is the problem since I have never heard of any problems before, could the throttle bracket be that far out of alignment because of the aftermarket casting from Champion? Thanks,

Datar

 

[BEATAV8]

the repop cable I bought could not hold adjustment either, with stock intake or the GN1. I tapped the hole in the "button" and inserted a screw with a jam nut to lock the adjuster tight.

 

[BEATAV8]

you can see the screw in this pic

 

[D's GN]

you can see the screw in this pic

Thanks Steve, I thought about elongating the upper 2 bolt holes of the throttle bracket slightly and compensate by sliding it forward but will try your fix first. Is the screw pulling the adjuster tighter? (pulling it out slightly to increase the clamping effect) Or is the screw physically stuck into the plastic slider with the ridges?


Datar

 

[Boost231]

more info how you did the jam nut. mine likes to click out just one click to much at wot. ive been trying to figure out how to fix it and that looks like the way to do it.

 

[SSedan64]

These also cure that problem:
http://www.sonnax.com/system/announcement/AS1-01K.pdf
http://www.sonnax.com/product-lines/high-performance-transmission/parts/1989

 

[Boost231]

^ anyone use it? mine is off just by one click but the throttle blade opens 100%. i think the jam nut will work but i wonder if i should try the spring deal. I was told i could use the spring but havent tried yet.

 

[BEATAV8]

more info how you did the jam nut. mine likes to click out just one click to much at wot. ive been trying to figure out how to fix it and that looks like the way to do it.

it's just a 10-32 screw. I ran a tap through the hole. Has a jam nut on the screw. Just turn the screw in till it locks the adjuster good-n-tite and then lock the jam nut so the screw can't wander.

 

[SSedan64]

Only question/worry I have with the Screw method, is the TV getting a full pull for max Pressure? Or is it being stopped slightly short of full pull @WOT?

 

[BEATAV8]

mine is set for "very tight" cable

 

[Boost231]

mine gets a full pull and bottoms out the valve. however it clicks one click to much which hurts my part throttle shifts. im going to try this method im pretty sure. i like it better then the spring deal but we shall see.

 

[hemi8]

I am interested in this as my head has been swimming with TV cable and TV position information. With the bolt installed in the adjuster like you have, have you verified you are getting WOT (throttle blade perfectly horizontal)? Did you drop your trans pan and verify the TV bottoms out at WOT and that the slightest throttle movement translates to TV movement as shown in the below pics?

 

[hemi8]

I have the GN1 intake as well and currently have the pan off and am looking into this today. I am interested in the placement of the TV cable position relative to the TB connection as it may be "off" due to the aftermarket intake. I'd like to think Tom went through this when designing the intake but ya never know.
Mike

 

[BEATAV8]

With the bolt installed in the adjuster like you have, have you verified you are getting WOT (throttle blade perfectly horizontal)? Did you drop your trans pan and verify the TV bottoms out at WOT and that the slightest throttle movement translates to TV movement as shown in the below pics? View attachment 172338View attachment 172339

Yes and No. Throttle does go WOT as desired, but I have not checked the TV valve position with the pan off. All I can say is that the cable has nothing left when the throttle is at 100%.

Car shifts at nearly 6000 RPM at WOT.

 

[hemi8]

Something is waay wrong with my set-up, fully connected and TV cable set per factory procedure I am a good 1/2" from even touching the TV plunger.

 

[hemi8]

Well, looks like I had reassembled the plunger ass-backwards, put it in properly and readjusted everything and its more inline with what I expected. The TV arm is about 1/8" away from the TV plunger and that is a throttle linkage geometry problem. It looks like the throttle bracket needs to go back towards the firewall just a small amount, problem is there is not enough metal on the bracket to elongate the holes. As far as I can see a new piece of metal needs to be welded on so those 2 mounting holes can be shifted back about equal to their radius.

 

[D's GN]

That is EXACTLY the problem I am having, I enlarged the holes on the bracket and slid the bracket forward to compensate which still was short over 3/16" or more. Modifying the bracket by welding another plate to it and drilling new holes is the only thing left for me to do. Looks like you have the same issue.

Datar

 

[BEATAV8]

When you go WOT can you get the cable adjusted so that the TV plunger to go all the way in? If so, maybe the 1/8" of slop at 0 throttle isn't important?

 

[D's GN]

At WOT the extra 3/16" pulls the cable out of adjustment. It loosens the tv cable off to the point where the shifts are soft/early and line pressure is a problem. Luckily I noticed this before I wiped the clutches/band on another WOT tuning pass. I just changed the TV cable from a re-pro aftermarket to a low mile stock one and it did not remedy the problem.

 

[hemi8]

Got the first part fixed. I elongated the 2 mounting holes and slid the bracket towards the firewall about 1/8", that little adjustment has now preloaded the TV plunger by no more than 1/16" which I believe is fine. When I hit WOT the TV adjustment does not change. I also installed a stud in place of the allen head plenum bolt and drilled a new hole in the bracket for a more solid bracket mount. If I did not mount the stud I would not trust it, but now its good and solidly held in place. If I did weld on a new plate I would also lower it so the TV cable would be in perfect horizontal alignment with the TB lever, right now its higher. I wouldn't drive the car without checking the TV plunger-to-lever relationship as pressure has to instantly rise at the slightest hint of throttle movement. This became more apparent with the install of the PTC NL converter.
Mike