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Who has the demensions and layout for one of these? I'd rather make one then pay these thieves $30 for one.
 

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Discussion Starter #5
Didn't realize jegs had a cheaper version. Ghetto, eh I spend plenty on quality parts, a $5 bracket for $30 is them knowing they have you over a barrel and take advantage. Thanks.
 

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63 SS
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I believe the one crazycar is talking about is for an Edelbrock carb. I’m looking for the exact same thing and I’ve been on all the websites. And just to clarify I was refering to getto on the action of buying and returning. :D
 

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Mike - 74 Nova Baltimore, MD
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Below is a link for the Jegs version of the 700R4 TV Geometry Corrector (kick down) bracket for the Holley carb.... but I advise NOT buying the one shown in the link below for use with any GM 700R4 or 2004R transmission.
https://www.jegs.com/i/JEGS/555/157300/10002/-1

The reason is that the Jegs bracket is an old design with incorrect TV geometry (shown below on the right).
The newer (Holley) version has the TV attachment pin lower and closer to the bolt hole (shown below on the left).

In a nutshell, the "newer" Holley version gives you a faster and higher trans fluid pressure rise when applying throttle from idle. This is exactly what you want to happen to keep from burning up your overdrive transmission. I was able to verify this with a trans pressure gauge while setting the TV cable on my 2004R.

Below is an image showing the correct GM TV geometry for the 2004R and 700R4 Trans. The image better illustrates the incorrect pin location on the Jegs TV bracket (blue line).
The RED lines with the BLACK dots illustrate the correct geometry.
The BLACK line represents the TV cable.


Using the illustrated GM TV geometry, I was able to build my own TV Geometry Corrector bracket (mainly because the correct Holley version was not available at the time I installed my 2004R).




If the newer Holley version was available when I needed it, I would have just purchased it.

NOTE: You will also need the Holley Throttle/TV Cable bracket too (if you have throttle cable).
https://www.jegs.com/i/Holley/510/20-95/10002/-1
The Throttle/TV Bracket is attached to the back of the carb stud in the image below.


If you have a throttle rod, you will need a different type of TV Cable holder... or you could just cut off the top throttle cable holder portion of this bracket - but only if your throttle rod clears the rest of the this bracket.
 

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Discussion Starter #9
Fortunately when I had my 700 built for high hp I also had them make a constant pressure so it will never burn up from the tv cable. Thank you for explaining and showing which corrector to buy. I do thing it would be as simple as enlarging a picture of it until the top hole diameter was correct therefore making everything dimensionally correct and transferring it to steel simply by tracing but I'll prob end up buying one....maybe.... I'm a welder so any time I can make something and better at that, I do. Thanks again rifraf!
 

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Mike - 74 Nova Baltimore, MD
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Fortunately when I had my 700 built for high hp I also had them make a constant pressure so it will never burn up from the tv cable.
Smart move! I've read many horror stories of burned up 700R4 and 2004R transmissions due to improper TV cable adjustment.

Good luck with the TV Geometry Corrector bracket!
 

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is there a way to tell if my 700r is built as a constant pressure ?
 

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Mike - 74 Nova Baltimore, MD
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is there a way to tell if my 700r is built as a constant pressure ?
The best way to be sure is to use a 0-300psi transmission pressure gauge to check the line pressure as you move the carb throttle from idle while the engine is running and the TV cable connected to the throttle bracket.
See link below for detailed instructions and the location of your transmission's pressure port.
http://www.tvmadeez.com/press_gauge/pressgauge.html

If you see a pressure of around 70lbs - 90lbs at idle... and you notice the pressure rise as you move the throttle to increase engine RPMs, you most likely do not have a constant pressure set-up.

Another way to check without a pressure gauge (but not as accurate) would be to start your engine and let it idle. Take the TV cable off off the throttle bracket and pull on the cable wire in the direction it would move as if the carb throttle was moved forward to increase engine RPMs (but you are only moving the TV wire... NOT the carb throttle). Pull the TV wire until it stops. If you notice an increase in the sound pitch from the transmission's oil pump (kinda a whining noise), you probably do not have a constant pressure set up in your trans.
 

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Not a very good drawing.I am trying to make a hookup for a holley and this is the dimensions I think are correct to make it. Mount it on carb, line up base, set linkage to idle point, pick up throttle center and step off these dimensions. Would like to know if these are correct.
 

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Mike - 74 Nova Baltimore, MD
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Not a very good drawing.I am trying to make a hookup for a holley and this is the dimensions I think are correct to make it. Mount it on carb, line up base, set linkage to idle point, pick up throttle center and step off these dimensions. Would like to know if these are correct.
Your measurements seem ok... but without knowing the angle of your geometry corrector bracket at idle (since idle position is not a constant), I can't say for sure if your measurements would work.

Luckily, I did find my original template that I used to make my geometry corrector bracket for my Holley carb.


I was able to use my template to take accurate measurments. You would cut your geometry corrector bracket to fit your carb throttle and drill the holes into the bracket using the diagram below.
NOTE: Please understand, I am not an engineer and just a automotive DIY. The measurements provided worked for me and I was able to achieve full TV pull at WOT while also achieving about 70-75psi transmission line pressure at idle. Anyone using these measurements assumes all risks and responsibilities.

Hole "A" and "B" are your carb throttle mounting holes on a Holley 4150 or 4160 carb.
Hole "C" is your TV kickdown attachment stud hole.


I also took the correct Holley carb geometry corrector for the 700R4 and 2004R trans and overlapped it on the diagram shown above. As you can see, it's a pretty good fit.


If you are installing the Holley TV kickdown stud (part #20-40), you will need to cut the stud flush with the back of the corrector bracket (while installed thru the geometry corrector bracket) and weld to the back of the corrector bracket. There is not enough room to install the nut. The uncut TV kickdown stud and nut will hit the carb throttle.
 

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The one you made looks very good. I have been playing around with these adapter for quite a while. Have burnt several clutches playing with them.

It seems to me to get the holes in the right place to match the gm diagram you would have to know what angle the arm is at idle. Like you said that is a variable and would change the hole location.

I tried to find that info on google but didn't have any luck. I would like to know what holley used to make their.

Thanks for the time you spent on this post, I am sure others will learn from it.
 

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I bought a Holley adapter for my Fitech efi. It does not put the transmission cable in the correct location. I sent it back and made my own. I printed off the drawing like what is shown above and cut the paper off to the right of the vertical and angle line. I had a punch mark for the throttle blade axle on my adapter and had the vertical line 90° from level. I scribed a line to follow the angled line of my paper cutout onto the adapter. I used my Vernier to accurately mark off the distance. Prick punch the intersecting lines and I now had an accurate location to finish off the adapter. Works perfect.

If you already have an adapter on your car you can print the above diagram slightly larger and measure off the 1.094 -1.125" measurement. Cut the right side of the line and compare it to your setup.
 

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Mike - 74 Nova Baltimore, MD
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I bought a Holley adapter for my Fitech efi. It does not put the transmission cable in the correct location. I sent it back and made my own. I printed off the drawing like what is shown above and cut the paper off to the right of the vertical and angle line. I had a punch mark for the throttle blade axle on my adapter and had the vertical line 90° from level. I scribed a line to follow the angled line of my paper cutout onto the adapter. I used my Vernier to accurately mark off the distance. Prick punch the intersecting lines and I now had an accurate location to finish off the adapter. Works perfect.

If you already have an adapter on your car you can print the above diagram slightly larger and measure off the 1.094 -1.125" measurement. Cut the right side of the line and compare it to your setup.
That is very similar to what I did when I made my bracket. The circle in the middle of my cardboard template (without any holes) represented my throttle axis. I then took my verniers and measured 1.120" and drew a radius line out from the throttle axis (you can just notice the pencil line that intersects the TV pin location in the image below). Then I used the GM diagram to locate the correct placement of the TV pin.
Oh... and the overall shape of my bracket. That was determined because I used a shelf bracket for my metal. I cut the angles at the bottom of the bracket just for a little more visual appeal :)


My issue was that I could only find the "older style" Holley geometry corrector when I originally installed my 2004R and I did not like the pressure rise off of idle. It seemed very slow and part throttle shifts felt soft. I think a lot of people may have installed the older version of the TV geometry corrector and never checked the transmission pressure rise from idle while driving (most people only check pressure at idle and full TV pull at 1500-1800 rpm).

While the pin location on the "older style" Holley geometry corrector was the correct distance from the throttle axis, it was located too high up in the radius of the axis. As a result, you had downward movement of the TV cable along with forward movement as you moved the throttle from idle. Downward movement is not moving your TV cable forward. The newer version has the TV pin located closer to the bottom of the throttle axis radius, therefore provide more forward movement off of idle. More forward movement is = faster pressure rise.

My recommendation is if you have a Holley 4150 or 4160 carb and a 2004R or 700R4 overdrive transmission, to just buy the newer version of the Holley TV geometry corrector... unless you are absolutely 100% sure you know what you are doing if you are attempting to build your own TV geometry corrector bracket. Burning up a transmission is not worth the cost of a $25-$30 bracket.

The slight differences in throttle position at idle will not effect the proper installation and use of the newer version Holley TV geometry corrector.

It is also extremely important that the TV cable be adjusted correctly and verify full cable pull at WOT. I also found that using an adjustable TV cable gave me more flexibility during installation.

P.S. Shane, that is an extremely nice looking Nova shown in your link :thumbsup:
 

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Below is a link for the Jegs version of the 700R4 TV Geometry Corrector (kick down) bracket for the Holley carb.... but I advise NOT buying the one shown in the link below for use with any GM 700R4 or 2004R transmission.
https://www.jegs.com/i/JEGS/555/157300/10002/-1

The reason is that the Jegs bracket is an old design with incorrect TV geometry (shown below on the right).
The newer (Holley) version has the TV attachment pin lower and closer to the bolt hole (shown below on the left).

Would this also apply to an Edelbrock carb? The TCI bracket looks like the incorrect Holley bracket, while the JEGS looks like the newer version like you stated RifRaf.
 

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