i just got my hands on a late 70,s c-4 out of a ranchero it had a m400 or 351m in front of it it has a R servo has anyone heard of this i knew of a A,C & H servos is this a rare tranny and is it beffier since it was behind a bigblock????
Lets call it an oddball.The bellhousing is very desireable to 429/460 guys who want to run a lightweight tranny.What gets me is the "R" servo.Most likely that has been swapped in there they are usually only found in the Hi performance fords Cobra jets,Dragpack cars etc..There is a possibility that the trans is a little more heavyduty but im not 100% sure
its came out of a ladys car who bought it brand new and the car only had 40,000 miles this is true ,the car had gotten wrecked
Yea thats really wierd must have been all they had on the assembly line at the time.R servos really firm up the shifts.
i just did some research and i dont find anything saying c--4 had a r servo only c-6 but who knows im happy with it anyways it should be plenty strong for my 70 maverick
The "R" servo was used in some cars and many truck applications. It has a slightly smaller apply side piston than the "A" servo but has a smaller release side. This is the servo that gives most of the 2-3 flair problems because it releases so quickly. Not a bad servo - you just have to plan for it and add a restrictor to make sure the direct clutches apply as fast as the sevo releases.
yeh what Paul said... sounds like he's got a grip on that info ! Always like reading the Mav Techies replies this forum has a plethora of knowledge.
The C4 that you have is the same on the inside as any other V8 C4. The front of the case is stronger but it has all the same internal parts as any other.
so the r servo is not the best to have ? sould i replace the R servo with a h Servo if i add more horsepower later? And does anyone know if this servo is the same used on c-6 trannsy that seem o desirable? Why did they use the R servo with this c-4 behind a bigblock just lots of questions i had thought might get a answer too thanx guys for all the info
It is not the same part that is used on the C6. The "C" servo is going to be hard to find but it will place the highest clamping force on the drum. The "H" servo is also rare but used more often than the "C" servo and is the next in line as far as clamping pressure. For any engine up to about 500 foot pounds of torque the "A" servo will be fine and it is one of the most available on the market. I use the "A" servo in most of my builds. The "R" servo is next in clamping power and the rest are not really suitable for anything over 300-350 foot pounds of torque.
thanx for the information ,and yes its a C-4 it has the removable bellhousing cause i replaced the bigblock housing with another c-4 i had for a small ford
