[ProjectX]

Quick question, I'm going to be installing a 2004r tomorrow and I just tried to move the th350 crossmember back as I've read, to see how it would bolt in. I see two bolt holes close together so I'm assuming the second hole to going back is one of the holes I'd use and I'd have to drill another hole for the furthest back crossmember bolt. The problem I see is if the second of the two holes that are close together is the one I use and I'd have to drill another hole further back would not work because the back bolt hole in the crossmember now sits off the frame. In other words half the hole is over the edge of the frame and the other part isn't over the frame at all. Am I missing something or do I just need to get an aftermarket crossmember or use a th400 crossmember? Also the back part of the frame seems to curve out where the back hole would go, so there is and indentation for several inches in the edge of the frame for the crossmember to sit in and that ends about where the back of the crossmember rear hole would sit.

Hopefully I haven't confused everyone. Thanks for any help or advice.

 

[Professor Fate]

I used a TH400 crossmember. Still had to elongate the holes a tad, but it was close to start with.

 

[Nova Thug]

According to this chart the TH200 4R and the TH400 share the same dimensions from the bell housing flange to the transmission mount 27 15/16”..

 

[RifRaf]

Your TH350 crossmember will not work for the 2004R. There is not enough room on the front subframe to move the crossmember back far enough for the 2004R.
If you use a TH400 crossmember, be sure that it was for a small bock set-up. A TH400 crossmember for a big block is offset to the passenger side.

When I installed my 2004R in my Nova (with a small block), I used the following crossmember from Summit Racing.
https://www.summitracing.com/parts/sum-770311

The Summit crossmember is very strong, fits great, and leaves plenty of room for the duel exhaust pipes. See note below for installation in 73/74 Nova.

When installing this crossmember into a 73/74 Nova, the front subframe and motor mount location is a little different than the front subframe in a 68-72 Nova. I had to cut a small notch and drill one extra hole into each side of the crossmember bolt access slots.

 

[ProjectX]

I ended up ordering the Gforce CM similar to the one from Summit. Should be here on Monday so looking forward to getting it installed.

 

[RifRaf]

Good choice! I believe that the GForce and Summit brand crossmembers are the same crossmembers.
When I ordered Summit brand crossmember, I remember it arrived with a GForce sticker attached to it.

NOTE: Be sure you get the TV cable adjusted correctly and use the updated TV geometry corrector bracket if you are using a Holley carb.
The old design with incorrect TV geometry is 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.

Good luck with the install!

 

[ProjectX]

Thanks for the heads up on the geometry corrector. I've got one from Holley so I'll pull it out of my parts box and check it tomorrow to see if it's the newer version.

 

[Osceola88]

Any update on the 2004r swap? I'm looking to do the same on my 74, I have a th400 crossmember already but I wanted to know how the Summit/G-Force crossmember worked out for you.

 

[ProjectX]

Sorry I just noticed that there was a response to this thread. I went with the Gforce crossmember and it is very beefy. I don't see this ever breaking, it's built like a tow hitch lol. It fit well the only problem I had is where the trans mount bolts to the CM. There is an oval shape below to access the bolts for the trans mount and it's slotted, but in order to fit the mount bolts are back on the edge of the oval. It's a pain to get a socket on the bolt but not impossible. Once it's in it's solid and definitely not going anywhere though. If the oval was a little bigger towards the back (in my case) it would be a perfect fit. If I ever have to take it out I'll enlarge the oval for better socket access. Let me know if you have any other questions.

I'm unfortunately still getting the car together and haven't driven it yet. Hoping to do so pretty soon though, it's been one problem after another with trying to get everything back in and fitting well.

 

[CVMA Dredd]

I replaced my TH350 on my '72 Nova and I used the G Force RCF1-400 crossmember "for Camaro F body '67-'69 ($229) for the TH400 and 200-4R" and it's worked perfectly.

 

[black73novaguy]

I also installed a 200-4R with the beefy G-Force crossmember and love it. Bolted up to factory subframe holes, and plenty of clearance to floor pan and exhaust pipes, and transmission pan too. There was trouble getting the motor mount frame stands aligned properly though. My 73 subframe had the clamshell motor mounts, and I converted to the older style short and wide motor mounts with the tall frame mounts. I had to elongate the 3 bolt holes to slide forward on the subframe, so the trans crossmember bolted up to the original subframe holes at the rear. This afforded me more room at the back of the motor right in front of the firewall and made tightening the bellhousing bolts a cinch. It even put my fan using a spacer over water pump pulley just inside the factory fan shroud which I'm sure helps cooling efficiency to boot. The throttle bracket geometry corrector for your carb is a must along with the mount bracket that holds the t.v. cable and throttle cable in place bolted to the rear carb stud. Depending what carb you run will dictate which brackets to use. Setting the proper t.v. cable tension is a whole other story, and definitely worth researching plenty. My Wife and I set it up with the transmission empty and pan off so we could see the valve lever under tension while we set the adjustment at the cable lock. Under full articulation its under complete tension to allow proper pressures throughout all driving scenarios. The 200-4R is definitely still somewhat of a secret and an easy one to pass on due to that cable set up. But totally worth it in improved drivability and lowered rpms on the highway. Gosh I miss driving my Nova, it's been too long. Stay motivated man, it's easy to let our projects linger when we hit roadblocks and other things, but getting it back on the road should always be the goal.

 

[ProjectX]

Definitely concerned with getting the TV set correctly. The builder assures me that he will walk me through the process and I'm definitely not planning to drive it until he assures me it's set correctly. Still working on getting things wrapped up and firing her up soon (I hope), seem's like every step forward is two steps back. That being said, I think in the long run all the extra effort will pay off. Same here it's been way to long since it's been on the road and I'm looking forward to getting to drive my Nova again

 

[Redrider66SS]

when you get that TV cable adjusted post the steps you did to get it correct. also is a 700r4 adjusted the same as a 200r4 ?

 

[RifRaf]

Definitely concerned with getting the TV set correctly. The builder assures me that he will walk me through the process and I'm definitely not planning to drive it until he assures me it's set correctly.

There are different set-up procedures depending on what type of TV cable you have... Self Adjusting or Universal TV cable?
The first step is to insure you have the correct TV Geometry Corrector Bracket based on the brand of carb being used (Correct Holley bracket referenced in post #6).
In a nutshell... After connecting the one end of the TV cable to the trans, you want to confirm that you have the other end of the TV cable pulled out to its farthest/tightest position when it is attached to the TV Geometry Corrector Bracket and the carb is at "Full Throttle" position.

Is a 700r4 adjusted the same as a 200r4 ?

Yes... and they both use the same TV Geometry Corrector Bracket based on the brand of carb being used.

 

[Redrider66SS]

thanks RifRaf for that info an pic. i guess this all about 4 speed over drives. well i had to go look at the bracket i have on mine. i'm running with that old style you pictured with a holley carb. all works good an ive put 4500 miles plus on the tranny-700r4. so now should i be freakin' out ? anyway were do i find that new style TV bracket ?

 

[RifRaf]

I'm running with that old style you pictured with a holley carb. all works good an ive put 4500 miles plus on the tranny-700r4. so now should i be freakin' out ? anyway were do i find that new style TV bracket ?

I don't think you need to be freakin' out since you have already driven 4500 miles without any trans issues. I think the first indication of a problem would be some noticeable slipping/flaring between shifts.

I just checked Summit, and it appears (based on the image shown on their website) that they are selling the correct/newer version of the Holley TV Geometry Corrector Bracket for the 700R4/2004R.
https://www.summitracing.com/parts/hly-20-121/overview/

Sonnax also appears to sell the correct bracket.
https://www.summitracing.com/parts/sox-as4-04k/overview/

And the Summit brand bracket also appears to be correct.
https://www.summitracing.com/parts/sum-700202?rrec=true

 

[ProjectX]

when you get that TV cable adjusted post the steps you did to get it correct. also is a 700r4 adjusted the same as a 200r4 ?

I will do that. I have done what RifRaf described for initial adjustment and I will speak with the builder to make sure there are no other adjustments needed.

 

[LS CHEVY II]

Here you go Mike.

You wont burn it up, but this is supposed to work more efficiently. Would change when able. Part 20-121


https://www.summitracing.com/parts/...81JZFeBWgctN4oL5ExvC7Sc07hA-FIehoCJk8QAvD_BwE

 

[Redrider66SS]

thanks everyone for the info. i know more now than i did 3 days ago.

 

[RifRaf]

Redrider66SS, If you do change to the newer style of TV Geometry Corrector Bracket, it would also be a good idea to check/readjust the TV cable setting.