Big Block Install Possible in Avanti II?

[Paul K.]

I have a friend with a '69 Avanti II and he is curious if it is possible to install a Big Block Chevy motor like a 454 in his 69 Avanti II. Would the modifications necessary be extreme and hard to get right? 

[Avanti83]

The major problems I can visualize are hood clearance, exhaust manifold interference with the steering and possible crank pulley issues. It won't be difficult to find the dimensions compared to an SBC and the mounts , etc should be the same.

The exhaust ports on the SBC and Stude engines allow for a stock ram horn style manifold to clear the steering. The even spacing of the BBC outlets will make building an exhaust manifold a bit more difficult.

I'll bet it can be made to fit as Olds engines have been installed and they are large also and even wider.

If he decides to go ahead, please keep us informed. Personally, in today's climate, I'd find a 400+ HP LS engine and use it IIWM.

Good luck, Bob

[Gunslinger]

This raises the question of why?  Besides the engineering involved and modifications and fabricating involved, the idea of adding even more poundage to a car with a heavy front weight bias doesn't make much sense beyond being different.  Techniques for building extreme horsepower small blocks are well established.  They may not have the extreme torque the big blocks may have, but those levels can be approached.

if your friend wants to do something different with far less engineering effort and mods, he should consider installing a LS-series small block...great power potential and less weight plus lots of go fast goodies available...that's the future of Avanti II development for someone who wants more performance.

Edited November 23, 2017 by Gunslinger

[Paul K.]

Thanks for the replies. For some reason he doesn't want and LS and I thing what he has seen has been very expensive. I mentioned he can build an LS on a budget and make a lot of power. Next time I see him, ask some more specific questions. 

 

 

[Avanti83]

I'm not sure why he'd want to build an LS, just find a good one in a yard. For a few thousand, I'll bet much less than he could build a BBC, he'll have 400 honest HP and a great tranny behind it. The computers can be reprogrammed and there are adapters to use the older style SBC mounts for a direct bolt on to the Avanti/SBC mounts. He'll just need to be sure he gets a rear sump oil pan.

That's exactly what I'll do if I want to re-engine one of mine.

[PackardV8]

Unfortunately, the Studebaker V8 has big block external dimensions and very small block dimensions inside.  That's fortunate for engine swappers, since the engine compartment was sized for the Studebaker V8, literally anything will and has been swapped in there.   Naturally, there will be differences of exhaust and oil pan, but the void is there.

And yes, anyone swapping for anything other than a built 400" SBC is wasting money just to be different, but his car, his money, his decision.

jack vines

Edited November 24, 2017 by PackardV8