Steve...what transmission and rear gear is in it?
Brad, it has a Torqueflite with a 3.21 rear gear. Currently, with the 440 and it's cam, I am running a PTC 2500 converter. It would be okay with a slightly tighter converter but it was not happy at all with the stock converter that was about 1800 stall.
I have been debating this subject for quite awhile. My original intent was to put a modern Hemi in the car along with the matching OD tranny but it takes more tunnel hacking than I feel like doing. The engine is a piece of cake fitwise. I think some guys are using one of the modern GM trannies and it takes less work, or, they use the old small block torqueFlite which takes none.
When I rebuilt the suspension, I used the Hotchkis stuff which is basically an autocross set up so that it turns very well but there is no lift in the front end. I was looking for a driver, not a racer. I can feel every pebble in the road, for sure. Going to lower profile 17" tires did not help that, either.
So, I have a three speed tranny with no overdrive and I pull 3100 rpm at 75 mph. When I decided I did not want to mess with a modern engine install with an OD tranny, and considered the suspension, I decided to build for torque.
I don't like high stall converters on the street. Buicks have spoiled me. I want to touch the gas and move instead of sitting there waiting for the rpms to move thru the converter slush. Yet, I still wanted some punch. Seemed to me that a stroker was the way to go.
The current 440 is typical of mopar engines of the day...pistons are about 0.060" down in the hole and the actual compression is about 7.9-1 instead of 9-1 and there is no such thing as quench. To top it, my engine has later model heads that are larger in volume than those of the time (1969) for my engine. Engine runs good, does not use oil or smoke, but the cranking compression is only 130 psi.
So, in an attempt to bandaid it, I order a set of aluminum heads that had 10 cc smaller chambers and I was going to deck them another 5 ccs which I estimated would put me a bit over 9-1.
I also considered buying a stroker kit and building a new engine but I don't trust any of the machine shops in the area and they probably know about as much about Buicks, which is zero, as they do Mopars...
Then I came across CME which is a mass engine builder but they also build a series of performance and race engines as well as pure customs and the price is right.
So, after an unexpected windfall, I decided to ship them my heads and assorted pieces and let them build me a torquer and break it in on the dyno for me. I could easily pull another 75 hp or so but then I need a looser converter which I don't want and it would be more temperamental pulling AC, or idling around town. It will be a 10-1 motor that will run on 91 octane so I think it will suit my purposes.
Unless, I were to buy a Gear Vendors overdrive....