: What are my engine replacement options - Current engine is a transverse HT4100



LeaLEllis
06-12-12, 05:27 PM
We have 1985 Cadillac Eldorado Biarritz that, surprise! had an engine failure. We had the transmission rebuilt and the body painted so we want to replace the engine with something that will give us another 10 years. My 17 year old son loves the car!

I am wondering if you can give me suggestions on what engine would easily fit as a replacement (and what year and model car I could find it in). I have a line on a rebuilt large block V8 diesel engine from an '81 Eldorado, but I doubt that it is transverse. If I could find a diesel engine that is transverse, would it require a lot of retrofitting since I currently have a gas engine?

My research has basically led me to the conclusion that I don't want to put in another 4.1L, and a 4.5L engine would work without alterations. I have also read about the Oldsmobile V8 engine, but haven't found enough information to know what car I should look for to find that engine.

Any tips would be greatly appreciated.

dennis93coupe
06-12-12, 06:41 PM
I personally think you would be better off staying with a block configuration same as what you already have considering the transmission you have, and many other things. Several people have swapped 4.5 and 4.9 in their car successfully. I could be wrong, but I believe the 81 diesel eldorado is transverse. Problem with a diesel that old is finding parts for it I would think. You might even be better off with a rebuilt 4.1, they are out there just have to look for it.

drewsdeville
06-12-12, 07:50 PM
No pre-'86 Eldo's were transverse configuration, were they? I thought they were longitudinal layout.

carnut
06-13-12, 03:30 AM
If in fact, you have an 85 Eldo, it is NOT a transverse engine. The engine faces front to back and is off set to the right with the transmission beside the driver side of the engine. Later transverse 4.1's, 4.5 and 4.9 will not work in your car. Your engine trans configuration was used from 80 thru 85 in Sevilles, Toronado's and Buick Riviera's. Some rebuilders do offer your engine with 4.5 piston liners and pistons to increase power. If you are not restricted by smog testing, look for a gas engine in a Toro. Best to buy a parts car to get the proper oil pan, oil pump, exhaust manifolds and brackets for steering A/C and Alternator. Any time you swap engines you are in for alot of work and problems to solve. Good luck!

dennis93coupe
06-13-12, 09:49 AM
If in fact, you have an 85 Eldo, it is NOT a transverse engine. The engine faces front to back and is off set to the right with the transmission beside the driver side of the engine. Later transverse 4.1's, 4.5 and 4.9 will not work in your car. Your engine trans configuration was used from 80 thru 85 in Sevilles, Toronado's and Buick Riviera's. Some rebuilders do offer your engine with 4.5 piston liners and pistons to increase power. If you are not restricted by smog testing, look for a gas engine in a Toro. Best to buy a parts car to get the proper oil pan, oil pump, exhaust manifolds and brackets for steering A/C and Alternator. Any time you swap engines you are in for alot of work and problems to solve. Good luck!

You're correct and I should have known better about the engine being or not being transverse. My Mom had a Tornado diesel somewhere in the early 80's, don't remember exact year, and only remember she had it for a couple years. It was more or less a POS after having left her stranded a few times too many. She actually had better luck with her Cimarron after that.

83CADMAN
07-18-12, 02:31 PM
Some rebuilders do offer your engine with 4.5 piston liners and pistons to increase power.
Cool! More HP for the HT4100! Any word on how they hold up?

Edahall
08-12-12, 10:02 PM
You might want to look into putting in an Olds 402. There was someone a while back who did that. My concern would be how the transmission would hold up.