HT4100 4.1, 4.5, 4.9 Discussion, 4.1 to 4.1 swap, how hard can it really be??? in Cadillac Engine Technical Discussion; my 84 hearse has a 4.1 engine. it is blown , i have a wrecked 84 seville 4.1 with super ...
Automobile(s): 1984 Collins hearse, 1979 Coupe , 1984 Seville,1990 fleet'
4.1 to 4.1 swap, how hard can it really be???
my 84 hearse has a 4.1 engine. it is blown , i have a wrecked 84 seville 4.1 with super low miles that runs like a dream but now handles like a nightmare, i know they are different (fwd vs.rwd) , but how much different is the actual block between the two? i figured i would have to swap the oil pan , exhaust manifolds, motor mounts, and distributor. but what i need to know is if it is possible or if i am chasing a pipe dream. i have both complete cars at my disposal, so whatever parts i would need are available. i have used the seville for parts to keep the hearse running, so i have found a few differences in minor parts such as the coil and tps, but nothing that should keep the swap from being possible. i cant afford to toss in a 307/350, so im using what i already have in front of me....
Even though the Seville is Front Wheel Drive it used the Read Wheel Drive version of the HT4100. It was not until 1986 that the Seville went to a Transverse drive train using the fwd 4100. The 84 used the THM325 transmission which mounts the engine longitudinally with the old BOP bell housing bolt pattern used on your 84 hearse.
You will have to change the pan over to the one in your 84 hearse. (and possibly the oil pump pick-up?) There will also be differences in the starter and accessories but these should exchange from your bad engine.