TH400 Governor adjustment

Indeed its a perfect match for motorhome, and until recently you could upgrade your modern motor-home with this transmission. Bruce Roe made a computer module that would convert the TH400 to a pseudo 6 speed transmissions specifically for motor-home. I am making my best to convince him to update his great work to my own gearbox...

To be honest, the bulky converter is what the motorhomes and the Ferrari do have in common. Based on my own experience, the smaller diameter converters do slip a lot at high speed which is detrimental to top speed. If this is true with modern converters, I guess that back then this was even worse, and I can hardly see how Ferrari could have afforded to lose another 10-20kmh on the car. So, yes, motor-home bulky converter with specific bolt-pattern.

 

Drove my 400i again today - more work related errands and this time I paid attention to the shift points, the response off the line and Im happy with how that all works. I dont want a higher stall speed if thats going to affect the initial jump the car makes when I hit the throttle at a green light. I like the response. The issue is how far I need to push the gas pedal down to make the car go as fast as I want it to go. And unfortunately no matter how far I push it, it doesn't meet my needs. After successfully experimenting with cams on CIS cars both 8 and 12 cylinders that say cant be used I think focusing on the engine would be money better spent. A hundred more HP would go a long way . Pistons, porting and cams mmmm mmmm......

 

The Bruce Roe unit controls a switch pitch torque converter, not really six speeds but two different stall speeds for the converter.
The problem is 2 1/4 tons of car motivated by an engine with nominal torque at the converter's stall speed.
The engines this trans was designed to serve behind had gobs of torque just off idle.
A 455" Buick would move a 400 off the line smartly and not complain about only 3 ratios.
Don't few of you already have looser converters?

 

Using wild cams will raise the power band further, increasing the need for a looser converter.

 

Have tried quite a few converters, and I do indeed have a switch pitch. In the motor home, the module allows for:
1st High Pitch >>> 1st Low Pitch >>> 2nd HP >>> 2nd LP >>> 3rd HP >>> 3rd LP

Chances are the stator solenoid is not fast enough behind a colombo at WOT. At full throttle the sequence will probably end up like
1st HP >>> 2nd HP >>> 3rd HP >>> 3rd LP

The convertor I currently have is a 1200/2200rpm. I am exclusively using the high stall position, as the lower stall does feel sluggish. Above 180kmh, 2200 feels a bit loose though, that's the only situation where the 1200 stall is more appropriate.

I've tried a 1000/4000 PAE convertor but it was really subpar. Performance wise the 1200/2200 Protorque was a major improvement, so aside from the quoted stall, the design of the convertor has a significant impact on performance. Engine is out and a new shiny 1800/3600 convertor is just ready to find its way in the bell housing... 1800rpm will probably be a good compromise for regular use. The 3600rpm stall gives me more margin for camshaft overlap.

 

I didn't say wild. Ferrari left so much on the table with their cam choices.