LT1 engine swap

[nuklear2g]

just bought a 64 skylark convertible .Previous owner says it has a 340 ,could be 300 because thats what they came with.i could not tell cuz i cant make out engine code on block (bluish color)-(redish valve covers). Either way i wanted to know would a 93-94 roadmaster LT1 engine bolt up with trans swap or would it be wise to drop $$ to get more performance out of the motor thats in it already .because i really dont know if the motor is original.Or just drop a 350 w/turbo trans and be done with it .I just want max buick performance w/out degrading the car appraisel price.

[bob k. mando]

i seriously doubt that the LT1 is going to have a BOP pattern bell housing so you'd wind up swapping transmissions as well.

this is because, although your engine came out of a Roadmaster, the LT1 is NOT a 'Buick' engine in any way shape or form. this is a 'Chevrolet' engine that's been dragooned into GM 'Corporate' service. this is likely to cause other compatibility problems you'll have to solve.

the only modern GM engine that has Buick roots is the 3.8L (and 4.1L?) 'Corporate' V6's. these engines were derived from the Buick small block V8 series (215,300,340,350) by lopping the front two cylinders from the engine. most of these V6's in RWD configuration should be near drop applications for you.

if you want a 'current' Buick v8 you'd need to check out something from Land Rover ... they bought the rights to the 215 tooling from GM back in 65 and were stilling using variations of the short deck Buick engine until 2004.

300 stuff is a little hard to come by nowadays although you can probably make a lot of the Rover aftermarket stuff work. 340 stuff is a LOT harder as the 340 was only produced for 2 years (66-67) and you can't swap intakes with the 300/Rover because the 340 has a taller deck height.

nothing on the top end of any of those engines can be swapped with a Buick 350 because Buick also changed the order of the Intake / Exhaust valves in 68 when the bored the 340 out to 350 cubic inches. other than that, the Buick 350 ought to drop in quite easily as well. and you can still find them as they were in production from 68-81.

as far as appraisal valuations go, if that Skylark really has a (non-original) 340 in it already, i don't know how much damage you can do to the selling price no matter what you choose to do. i suppose it's a balance between the cheap power you can build with a chevy engine versus the extra time/expense/fabrication you're going to have trying to put a Chevy/LT1 in the engine bay.