Haggisbash

After changing my diff from a 3.08 to a 3.55 as expected the speedo is out by 8 mph. The car is fitted with a 200-4r trans and I have bought the speedo drive & driven gears to correct this but have to drop the pan to change the drive gear. While I'm in there I was considering what can be done with the governor to increase my up-shift rpm's at WOT as the upshift point at the moment is a rather low 3000 rpm. I have been reading everything I can find on the web about this but there is some conflicting info out there. Has anyone here had any real world experience with these governors? Also, does anyone know where I can buy one? (haven't seen any on e bay etc.) The 200-4r was not used in any local market cars sold here so local dealers are out.
I would rather experiment on a spare so if it all goes pear shaped at least I can put the original back in!

76strokervette

My 200-4r was built by one of the best out there with billet parts and modified governor.If you are interested send a pm and I'll give you his contact information.

'75

Best place to find info is on Turbobuick.com , the best 2004r builders in the nation hang out there.

Blue79

I agree with the reply to log onto the Buick transmission tech talk web site. I have the CK Performance 2004R manual and believe Chris at CK can set you up right or you can experiment with his directions in the manual and make your tranny shift as desired.

diehrd

http://www.442.com/oldsfaq/oft200.htm

speedreed8

gn governor

dugsgms74

Normally, the heavier the springs or the lighter the weights the higher the shift points. Unfortunately, theres alot of trial and error to get what you want, might be easier to see if you can get your hands on a GN governor.

In the simplest of terms, there are two different pressures working on the ends of the shift valves. One side is TV(throttle valve) pressure and the other is governed pressure. Governed pressure is directly related to road speed and TV pressure is related to engine load(th400) or throttle opening(th2004r/th350). When governed pressure is higher than TV pressure(high road speed/low engine load) the shift valves move to the upshift side of the bore, when TV pressure is higher than the governed pressure(low road speed/high engine load) the valves are forced to the downshift side of the bore. When you mess with the governor weights/springs all you're doing is changing the amount of pressure on the governed side in relation to road speed. Installing heavier springs or lighter weights means that the vehicle will now have to be moving faster to achieve the same amount of governed pressure as before.

Haggisbash

Thanks for that explanation, so my thinking (contrary to what I have read) is that the light weight will be the final signal for the WOT shift point because it is lighter than the big weight. So my thoughts were that lightening this weight should move the WOT shift point higher whereas the big weight would affect part throttle up-shifts working in conjunction with the TV cable. Correct me if I'm wrong as I have no experience with Auto boxes before I got the vette!

dugsgms74

I think youre on the right track there but thats where the trial and error comes into play. You can do alot of tuning to it with changing the weights and springs but it kind of becomes complicated as all three things have different effects. Thats why its kind of nice just to get a GN govenor, all the parts are made to work together, they are available still, usually you can find them on ebay.

Haggisbash

Okay I will look for a GN governor and start with that!
Have e mailed CK performance, so far no reply, I find that about 7 out of ten sites don't bother replying, maybe because I'm on the other side of the world.

Haggisbash

Been doing some more reading and the word was that the GN governor wont work with a std valve body apparently the trans wont up-shift until north of 7500 rpm if at all. Tad too much for my near stock engine methinks!

PcolaPaul

Look at the 80's Monte Carlo SS with the 200R4 for a governor. My stock 86 Monte SS has a 1/2 shift at 5300 rpm WOT.

'75

The performance governors need to be paired with the correct performance valve bodies to work correctly. Mixing and matching can produce poor results. It's much easier to lighten the light side of the governor you have and or go with a lighter spring.

Haggisbash

I'm chasing CK performance to see what they can offer as I like the look of their shift recalibration kit as I feel my 1-2 2-1 shift is too hard at part throttle setting and this looks like the fix but so far no response to my e mails. They offer assistance with the governor on their website but as above....
FWIW I found a governor on BowTies site which would lift the WOT shift point to about 4800 I could live with that.

76strokervette

I agree this is probably the governor you will want.If you want I can call Vince and see what he can do and maybe help you source some parts.Look up Vince Janis in the turbo buick community he has a stellar
reputation and is a straight talker.I know people running 750 + whp with his transmissions with no problems(200-4r).

Haggisbash

Hi 76SV, that would be much appreciated:-)

76strokervette

Just got off the phone with Vince and he said he can hook you up with the parts you need.Pm me and I'll send you the contact info.

Haggisbash

Thought I would update this thread in case it helps someone else.
I ended up getting another valve body, servo and governor from Chris at CK Performance. The governor raised my shift points at WOT to approx 4800 which is fine for me. The modified valve body and servo have fixed the bang shifting issue I was having, the shifts are quick, positive but not harsh. So its been a long road to get to this point but worth it, the transmission feels like a completely different unit now and I guess it is now that it has had a brain transplant. All mods done without pulling the trans from the car. I have come to hate the drip drip drip of ATF though.