Valve body differences

[65skyturbo]

I'm looking to expand my knowledge on these 2004R valvebodies. Are the castings all the same? I know that the springs and some of the bushings/valves are different between different VB codes. Are some of the castings bored larger than others? I have read that the OG is crap and should be avoided. How much is corrected with a good shift kit like CK's or Transgo? How bad is an HC2 valvebody (with Transgo HD2 kit) because that is what I currently have? Would an AA trans VB be a better one to start with? What differences in performance would I notice with a different VB? What other VB codes are easy to find at junkyards that make good starting points? Thanks in advance for the info.

 

[SSedan64]

I'm looking to expand my knowledge on these 2004R valvebodies. Are the castings all the same? I know that the springs and some of the bushings/valves are different between different VB codes. Are some of the castings bored larger than others? I have read that the OG is crap and should be avoided. How much is corrected with a good shift kit like CK's or Transgo? How bad is an HC2 valvebody (with Transgo HD2 kit) because that is what I currently have? Would an AA trans VB be a better one to start with? What differences in performance would I notice with a different VB? What other VB codes are easy to find at junkyards that make good starting points? Thanks in advance for the info.

I've heard/read that the AA works fairly well. Read thru this thread, there's a list I posted with trans/VB codes on the last post.
http://www.turbobuick.com/forums/transmission-talk/263025-kc-valvebody-cammed-ported-head-tr-2.html
Todd

 

[65skyturbo]

Thanks for posting that list. It used to be all over the net but lately finding it has been nearly impossible.

 

[SSedan64]

Thanks for posting that list. It used to be all over the net but lately finding it has been nearly impossible.

Yes, the site was Hometown AOL or something like that. Aol shut it down without notifying anyone. 10,000's of people had personal web pages,family pictures etc.. on that free site and lost all their info. I read some of the complaints from the members, they were piissssed.
I kept trying to send it thru emails & PM's but for some reason it didn't work. So I just typed it in the post, took forever trying to make sure it stayed inline & didn't get scattered.
Welcome, Todd

 

[bison]

I'm looking to expand my knowledge on these 2004R valvebodies. Are the castings all the same? I know that the springs and some of the bushings/valves are different between different VB codes. Are some of the castings bored larger than others? I have read that the OG is crap and should be avoided. How much is corrected with a good shift kit like CK's or Transgo? How bad is an HC2 valvebody (with Transgo HD2 kit) because that is what I currently have? Would an AA trans VB be a better one to start with? What differences in performance would I notice with a different VB? What other VB codes are easy to find at junkyards that make good starting points? Thanks in advance for the info.

There are many combos. If you have cam, heads and turboo then you should consider raising the shift rpm well above the stock calibration for better et's. For slightly modded cars with heads and cam up to about 500-550 hp the CZ vb/governor will work well and extends the WOT shift rpm about 400-500. For even later shifts the KC with a BR governor seems to be working really well in several cars on here. Its currently what i have and it shifts around 5900 at WOT. Jake reported that CR vb with a BR governor produced good results in a modded TR. Code AA works fairly well in TR's. Some of the high performance vb's have a slight variation to the bore size in one spot. The springs and valves vary in each calibration.

 

[65skyturbo]

My application is a little different than most. I have a 2004R in a 65 Skylark that currently has the original 300ci 4bbl. Later this year it will be getting a mild LS1. Right now I have the HC2 valvebody with a MCSS governor and it seems to shift around 4900 WOT. Probably a little high for the 300 V8 but when I install the LS1 I will want it to shift higher. Likely something around 5500-6000 depending on the cam I run. How much rpm difference is there between the MCSS gov. and the BR governor?

 

[bison]

My application is a little different than most. I have a 2004R in a 65 Skylark that currently has the original 300ci 4bbl. Later this year it will be getting a mild LS1. Right now I have the HC2 valvebody with a MCSS governor and it seems to shift around 4900 WOT. Probably a little high for the 300 V8 but when I install the LS1 I will want it to shift higher. Likely something around 5500-6000 depending on the cam I run. How much rpm difference is there between the MCSS gov. and the BR governor?

It depends more on the vb calibration more than the governor. You will have to switch vb's to get anywhere near 6000rpm shift points. There is not a lot of difference between the 2 governors mentioned.