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Throttle body spacer

Blue90

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Okay now I've just installed a throttle body spacer on my 1990 blazer with the 350 5.7L in it. Horse power went up and all that good stuff, but the shift points changed. They shift more hard and at a higher RPM. It's not that I dislike this change, I just wonder why it's doing this. I checked all the vacume lines and everything involved around there, nothing seemed out of place. Any Ideas?:confused:
 
Yor TV cable may need to be adjusted. the dealer charges 45 bucks to do this. If its shifting hard you need it done or you will end up with installing a new tranny.
 
Yes, redo your tv cable before you burn it up.

In case you dont know how to do this.
1. Push button or release clip so cable sheath moves freely in its mounting position.
2. Have someone inside push throttle all the way down.
3. Push on sleeve so its pushed back all the way.
4. Release button or push clip onto sleeve so it can no longer move.
 
Adding the height of the spacer in there caused your tv cable to become out of adjustment. The tv cable hooks up to the tbi on the side where the throttle linkage hooks up. Ive never been able to use the method stated in the post above.

You can take a pair of pliers and push in the "D" shaped button on the tv cable (after you have unclipped it from the bracket). With the button pushed in, the sheath moves freely by "clicks" back and forth. Move it a click or two in one direction and then test drive. If it gets worse, adjust the cable back the other way. I use this "trial and error" method whenever I have had to adjust mine. It usually takes me 5 or 6 tries to get it right. I just adjust it until the tranny shifts when I want it to. You can hear when the engine needs to shift....judge it from there.

Whatever you do, dont drive it for very long if its out of adjustment. The tv cable adjusts main line pressure in the tranny, and if its way out of adjustment, it can burn up your tranny in a matter of miles.:eek1:
-Harrison
 
neverendingproject said:
Yes, redo your tv cable before you burn it up.

In case you dont know how to do this.
1. Push button or release clip so cable sheath moves freely in its mounting position.
2. Have someone inside push throttle all the way down.
3. Push on sleeve so its pushed back all the way.
4. Release button or push clip onto sleeve so it can no longer move.

Well, actually, it should be 1, 3, 4, 2... :wink1:

you release the cable by pushing the D-button, push the sheath all the way in towards the firewall, release the button..

full throttle it, and your done... it'll normally make a couple clicks when full throttled...
 
87BrnRsd said:
Adding the height of the spacer in there caused your tv cable to become out of adjustment. The tv cable hooks up to the tbi on the side where the throttle linkage hooks up. Ive never been able to use the method stated in the post above.

You can take a pair of pliers and push in the "D" shaped button on the tv cable (after you have unclipped it from the bracket). With the button pushed in, the sheath moves freely by "clicks" back and forth. Move it a click or two in one direction and then test drive. If it gets worse, adjust the cable back the other way. I use this "trial and error" method whenever I have had to adjust mine. It usually takes me 5 or 6 tries to get it right. I just adjust it until the tranny shifts when I want it to. You can hear when the engine needs to shift....judge it from there.

Whatever you do, dont drive it for very long if its out of adjustment. The tv cable adjusts main line pressure in the tranny, and if its way out of adjustment, it can burn up your tranny in a matter of miles.:eek1:
-Harrison

You don't want to adjust it this way because you may still not get it right. The cable needs to be fully pulled at full throttle to be set right.( sheath pushed all the way back while holding full throttle.) Sound like yours is pulled a little too much because of the extra reach needed for the spacer. That is not as bad as not enough pull. You have effectivly increased your line pressure which is what is making is shift harder and later. You are probably not getting full throttle on the throttle body now because you are being limited by the tv cable. Try mashing the peddle to full throttle real hard and the cable should pull out a bit and adjust itself.
 
ryoken said:
Well, actually, it should be 1, 3, 4, 2... :wink1:

you release the cable by pushing the D-button, push the sheath all the way in towards the firewall, release the button..

full throttle it, and your done... it'll normally make a couple clicks when full throttled...

Well I dont have the original cable, nor does anyone wround here sell them. Believe me when I tell you mine does not have this ratchet action that its supposed to. Mine has a c-clip like thing that holds it and no d shaped button like the original did.
 
what should the shift point be??? mine shifts at arround 4200rpm out of first. I think its fine but the guy that test drove it this weekend said it was too high.
 
blue90 said:
Okay now I've just installed a throttle body spacer on my 1990 blazer with the 350 5.7L in it. Horse power went up and all that good stuff, but the shift points changed. They shift more hard and at a higher RPM. It's not that I dislike this change, I just wonder why it's doing this. I checked all the vacume lines and everything involved around there, nothing seemed out of place. Any Ideas?:confused:
Like the other posters wrote, the TV cable needs re-adjusted.

Why did you need to install a TB spacer? Did you need some extra clearance for non-stock equipment (linkage clearance, for example), or was it to get amazing gains in fuel economy and power (simultaneously, no less)?
 
Hmmm...

Well it sounds like I'm goin to adjust the tv cable. Thanks fellas, :bow: I put the TB spacer on for horse power and fuel echo. I definatly noticed the power increase. As far as gas goes I'll know when I get to the pump. :eek1:
 
blue90 said:
Okay now I've just installed a throttle body spacer on my 1990 blazer with the 350 5.7L in it. Horse power went up and all that good stuff, but the shift points changed. They shift more hard and at a higher RPM. It's not that I dislike this change, I just wonder why it's doing this. I checked all the vacume lines and everything involved around there, nothing seemed out of place. Any Ideas?:confused:

Hi guys, I have been merely reading for the past five (5) years:o , you know, building knowledge!!
I believe you need to install a bracket instead of the existing one. The new bracket should take care of the new elevation that got added by installing the TBI spacer.
 
afgg2001 said:
Hi guys, I have been merely reading for the past five (5) years:o , you know, building knowledge!!
I believe you need to install a bracket instead of the existing one. The new bracket should take care of the new elevation that got added by installing the TBI spacer.
You can install a drop bracket if you want to. However, adjusting the tv cable will work just fine and its free (unlike the bracket).
-Harrison
 
bdozeraz said:
You don't want to adjust it this way because you may still not get it right.
Adjusting it this way has worked fine for me. I did it like this around 3 years ago to mine when I replaced the motor and had no problems. I installed a tb spacer and taller edelbrock intake a while back and had to re-adjust slightly. Still working fine. Its not rocket science. If its holding the gear till 5500 rpms, then it needs to be adjusted. If it shifts at 3500 at wot, then still no good. Not really as hard to get right as everyone thinks....
-Harrison
 
Done and done

I got er all adjusted and she's runin great. Thanks again.:D
 
87BrnRsd said:
You can install a drop bracket if you want to. However, adjusting the tv cable will work just fine and its free (unlike the bracket).
-Harrison


Actually, its not a different bracket.. Most TBI spacers come with corresponding spacers that go under the manifold bracket.. Longer intake bolts, 1" spacers and it corrects the cable geometry.. In some cases, without the spacers, you cannot get the cable adjusted properly due to cable length...

There was a HUGE freakin thread on this about a year ago... There's also LOTS of misinformation bouncing around in this thread...

Everyone please read thru http://www.tvmadeez.com/article/index.php
 
ryoken said:

Very informative read.

I did know exactly how the tv cable works, and what it did to regulate pressure. I adjusted mine the way I stated earlier, and have had no problems whatsoever for the past 3 years. Do what you will but im always going to adjust mine like I have in the past (if it ever needs adjustment again). I have a tb spacer and performer intake so my geometry will never be right. Therefore, the "correct" method isnt going to be spot on anymore.

Call me old fashioned but I dont usually do things exactly by the book. People have flamed me before for not using a torque wrench....i.e. I dont use a torque wrench for ring gear bolts, hub bolts, or intake bolts. I have never had any of the above fail because I didnt use a torque wrench.

Anyways....im not trying to start anything here. That was a very informative and accurate link ryoken. Im just merely stating that I didnt do it that way and have had no problems. But...awesome link man. Good find.:wink1:
-Harrison
 
I would think the bracket spacers would work fine with the performer.... Can't see why not.. But it's here nor there if the truck runs ok....

I'm just not a fan of the "couple clicks" test run idea... The whole time your driving it and its off, your hurting the tranny... But hey, if the trannies holding up now, more power to ya... :D

700r4's have a bad enough rep, we don't need more people blowing em up.... :haha:
 
ryoken said:
700r4's have a bad enough rep, we don't need more people blowing em up.... :haha:
I agree. Mine has held up fine so far...(knocks on wood...crosses fingers)
Im sure it will eventually go...I aint exactly what you would call easy on it.:D
-Harrison
 
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