Hello, I am in the middle of an engine swap from a V8 4dr to a 250 6 2dr. This seems to be a long term project that I am dragging out. Anyway, I pulled the engines several months ago and have both engine bays painted and ready to swap back in. I recently noticed the V8 car is a 164 bell and flexplate with the 250 six a 157. I had assumed they would be both 157's. I think I should swap bellhousings and torque converters keeping the original flexplates on the respective engines. I don't plan on headers so clearance should not be a problem. Can the torque converters be swapped without driveability problems? It may be easier to swap flexplates; however I was told there is different balancing for I6's as opposed to V8's. Is this a fact? Also is there any advantage of retaining the 164 flexplate for the V8? Would i be better off tracking down a V8 157/160 tooth flexplate and bellhousing? Thanks for your input or opinion, Kevin
If I'm not mistaken, the sixes are internally balanced and the flywheel/flexplates are neutral balanced. Just a quick look at your six's flexplate will tell you for sure. If it lacks a counterweight, it's neutral balance and will not work on the V8.
You cannot use the six cylinder flexplate on the V8 or the othr way around. If you have the large bell on the V8 C4 you may not be able to change bellhousings because most large bells bolt to the case and the small bells bolt to the pump. You can swap the engine and transmissions as a unit - this is what I would recommend. Be sure to use the same plates between the engine and bellhousing (keep everything together in the swap.
Thanks for the advice. I did see there was no external weight on the 6 cylinder flexplate. It was my hope to avoid switching transmissions. I looked at the bolt pattern on a loose 164 bellhousing from a 1982 t-bird. The bolt pattern seemed to line up directly on a piece of cardboard with an 157 bellhousing. If the bolt patterns are the same does it matter if it bolts to the pump or case? Am I correct in assuming it should still position the torque converter in the proper position for bolting to the firewall?
The bellhousing pattern at the block is the same - where they bolt to the transmission is different. The large bell has bolts that go into the case and the small bell bolts to the pump.
Correct me if I am wrong here Paul but isn't the difference in the trans to bell bolt configuration something like this? Case fill = bolts to the pump Flywheel tooth count not a factor. I have all 3 bell housings for a V8 pattern (164, 157, Mustang II) and 170/200 I6. Maybe even one for a 2.3 I4 may be more. Oh yea, and even one for a 64 289 5 bolt V8 bell housing. Pan fill = bolts to the case Normally called a C-5 found in some trucks and some full sized cars. All I have seen of these are 164 tooth
In both transmissions the dipstick tube looks like a pan fill. Would that not indicate the same bolt pattern on the transmission (case mount) for either the large or small bellhousing? If the pump shafts are the same length and have the same # of splines, and the bellhousings are same length (or height if they are both out on the concrete floor), would not a swap of both bellhousings and torque converters line up with the respective flexplates? Perhaps the best way to verify is to measure the torque converter studs depth with respect to the block surface of the bellhousing, remove the torque converters, verify mounting pattern of bell to transmission, attempt the swap, and verify that the depth of torque converter stud to bellhousing is the same.
If the dipstick tube connects to the pan then it is a pan fill. If the tube goes into the case on the right (passenger) side then it is a case fill. The C5 is an upgraded C4 that was introduced in the early 1980s. The large bell C4s existed long before that.
