75mm BBK throttle body problems

[vroomzoomboom]

Glad you got it figured out.
If you try the BBK again, you can release tension on the spring. Like you, I don't like there to be more tension than needed, so I did this with a 70MM BBK.

you gave me a idea. i have the other 5L stock body sitting here that i used for the throttle linkage. i wounder if the spring from that would work. i will have to give it a try.

 

[Jakee]

It's all in how many times you turn the shaft when putting it back together. (You have to take the plate and shaft out of the TB to know what I mean)

 

[vroomzoomboom]

so i gave this yet another shot.
i thought i just about had it this time. i tested the TPS on the bench, and adjusted the throttle blade to closed when at idle. i had the voltage reading .99 at idle, and 4.67 volts full throttle. i left it like that, then put it on the truck. it would swing to full throttle no problems (had the same voltage on the truck as i did on the bench). started it up, idled fine. took it for a spin, it seemed like it hit WOT. still didnt shift as hard as it should, but it was close enough. even most of the whistle was gone. i was happy. seemed like i had it beat.
then last night i went for a ride to a friends place. you need to take the highway to get there. then it happened....i had it in cruise and could hear the motor serge 200 rpms, but not jerk the truck around. first i thought the cruise was buggering up. so i turned it off, and drove it as steady as i could, and sure enough, the motor would surged about 200 rmp. i took the bbk off, put the stocker back on, and no surge. this thing is really pissing me off now.

 

[Jakee]

I'm wondering if the seals are bad (where the throttle plate rod enters the TB).

 

[vroomzoomboom]

i would have to think if that was the case, i wouldnt be able to control the idle. still have it sitting on the bench, but its bugging me. i may try new O rings just for farts and giggles

 

[Mr.Blue]

Ever get this figured out?

 

[Turdle]

so i gave this yet another shot.
i thought i just about had it this time. i tested the TPS on the bench, and adjusted the throttle blade to closed when at idle. i had the voltage reading .99 at idle, and 4.67 volts full throttle. i left it like that, then put it on the truck. it would swing to full throttle no problems (had the same voltage on the truck as i did on the bench). started it up, idled fine. took it for a spin, it seemed like it hit WOT. still didnt shift as hard as it should, but it was close enough. even most of the whistle was gone. i was happy. seemed like i had it beat.
then last night i went for a ride to a friends place. you need to take the highway to get there. then it happened....i had it in cruise and could hear the motor serge 200 rpms, but not jerk the truck around. first i thought the cruise was buggering up. so i turned it off, and drove it as steady as i could, and sure enough, the motor would surged about 200 rmp. i took the bbk off, put the stocker back on, and no surge. this thing is really pissing me off now.

Did you happen to notice if the TPS voltage was holding steady?


I might have missed this earlier-How are you providing vacuum?

I'd like to see the difference in vacuum during cruise-I wonder if the lager throttle body is killing the vacuum causing vacuum operated functions to "wander"

 

[vroomzoomboom]

Did you happen to notice if the TPS voltage was holding steady?


I might have missed this earlier-How are you providing vacuum?

I'd like to see the difference in vacuum during cruise-I wonder if the lager throttle body is killing the vacuum causing vacuum operated functions to "wander"

gave up. took it off. its now a book end