Submitted by: Craig McCormick
Question: Can I use the same computer, sensors and carb from my original L69? Answer: Yes, in fact I recommend it. This will allow you to stay legal. You can also use the same exhaust manifolds, intake manifold and accessories. The exterior dimensions of the block are the same. Question: What about the stock intake manifold? Answer: The stock intake is a dual-plane aluminum manifold and works pretty well. If you are using centre-bolt heads you will need an intake manifold that's made for these or else be prepared to do some drilling and modification. There are upgrades available but IMO there are other upgrades that need to be done first. Question: Does the computer or carb need to be adjusted for the extra cubic inches? Answer: It does not HAVE to be but it helps to use different secondary metering rods in the carb. Some people have recommened using rods from a late 70's Caprice. In my opinion you don't have to make any changes to the computer but there are different opinions about this. Question: Will my original 200-4R tranny work with a larger engine? Answer: Yes, it will bolt-up no problem. The extra hp may shorten its life a little but with a proper rebuild it will be just fine. You could also upgrade to a 700-R4 but this involves modifying the cross member, shortening the drive-shaft and fiddling with the shift linkage and kick-down cable. Question: What about the knock sensor and other electronic sensors? Answer: The knock sensor threads into one of the drain holes at the botton of the block so that's no problem. The L69 block has a threaded hole just above the oil filter for the oil-pressure sender. Other blocks might not have this hole (mine didn't). You can either drill and tap a hole here or else tee into the oil-pressure switch that's under the distributor. There's a water temp switch that goes into one of the heads but I believe all heads have provision for this. There are some other sensors in the intake but if you're using the stock intake then this will not be a problem.