Technical Stroking 289 - Budget Build

The C6 was the main reason Ford trucks of that era got such poor fuel economy. They're nearly bulletproof, but also have the highest internal drag compared to all others at 45-50 HP. The C4 is only about 15 HP.

The 5-bolt C4 bell was only used on '64 289s, the 260 got the 2-speed trans (the only true 2-speed Ford ever built/used, starting in '59) and that was gone in '64 (except for leftover 260s Ford used up in early '65 Mustangs).

 

It is my understanding that the early C4's were case filled and later ones pan filled. I don't know where the change is. I think they were referred to as C5's?

 

C5's have a larger , locking torque converter. They USUALLY have a pan fill tube. They will have a larger bell housing to accomodate the torque converter.

 

The five bolt bellhousing was also used with the 221 engine. All 62 to 64 small block engines were five bolt, but the confusion comes in because the earliest pony cars should have been 64 models (with five bolt bellhousings) but for marketing purposes were called 65s.

And the flywheels / flexplate imbalance on the 221 and 260 were each a little different from the 289. But probably not enough to worry about unless one is very persnickety.

And one other ***bit: In Canada we were treated to the two speed Fordomatic for the 1964 model year as well, and a non-synchro three speed manual.

 

My 64 first year for the c4 is in the case, I swapped a 71 C4 by using the original bel housing from my Fairlane. Now if you find a transmission from 1981 it could be a C5 and not necessarily what you want.

 

My 67 is in the case. The tube ran so far down that I thought it went into the pan but I found some pictures of what those C4's look like. Thanks

 

Just do a 331. Jim Wood @ Ford Strokers did my balance work and recommended the camshaft profile. Runs on 93….

 

Just curious how did the transmission input shaft hold up?

 

My original 289 was only warmed up to 300 hp so it was fine but I had I new 71 from a maverick built for the new 450 tq/hp 289 the builder’s opinion was the OEM input shafts were better based on the failure rate of the aftermarket parts he had seen below 600hp.

 

From my research the 1970 C4's were the only year that had the 26/26 input spline shaft. From 71 it changed to a 26/24. If I do come across a good 70" C4 donor that might just need a rebuild I will definitely grab it. Any suggestions on a converter brand off the shelf.

 

I use a JW 3200 Sportsman
I believe Summit sells JW products
https://racewithjw.com/product-category/torque-converters/