Engine Swap Compatibility

I’m considering the purchase of a 1961 Chevy C-10 Apache pickup truck with a 235 c.i. “Stovebolt” 6-cylinder engine and a “3-on-the-tree” manual transmission. I would like to put a bigger I-6 engine in sometime down the road, and I wanted to know whether or not a 292 c.i. straight-6 would be a direct bolt-in replacement, or should I try for a 261 c.i. six instead?

Right up my line. I say stick with the 235 but bore it and put a hydraulic cam in it. These blocks will take a .090 over bore. I built one of these 235’s and could run away from 292’s quite easily. The weak spot on the 235 is the head, they will crack.

The best swap I made was getting rid of the 305 V-6 in my '65 GMC and putting a 330hp small block with a built Turbo 350 in it. That was a sweet running combo and managed to allow me to aquire my last speeding ticket.

If you make a swap,go small block. If you stay with the 6, you can pump the 235 up a good bit.Then again it all depends on what you can get and at what cost.

Clifford performance parts has been in business for decades, specializes in 6-cyl engines. I would also either modify what you have, or swap in a small block v8 if that’s not enough.

http://www.cliffordperformance.net/Merchant2/merchant.mvc?

I like that you built a 235 that could walk away from a 292, sounds great! However, I’ll elaborate on my previous question. I know that the '61 Chevy Apache half-tons came with either a 235 or a 283 V-8, and I believe some of the 4x4 K10’s could be had with a 261 I-6; that being said, I was thinking that instead of a V-8 I could put a larger 6 in this particular truck and get some decent gas mileage, while still having some very respectable stump-pulling low end torque. I’m not really looking for a hot performer, but rather something that looks good and yet can still be used as a work truck at times. I do think it would be a neat trick to see a 50-year-old Chevy Apache workhorse kick some sand in the grille of a new Toyota Tundra, but I’m not really looking to do that. A good, solid, reliable stock-appearing truck that can work with some of the best would suit me. I’ll probably want to lift the suspension a few inches and put some slightly oversize all-terrain tires on it too. What do you think?

The engine won’t make that much difference for gas mileage. Put a V8 in it and gear it for fuel economy.

The bad deal with that Chevy truck is the rear suspension design. My GMC had full leaf springs but I think you Chevy has those long arms connected to the rear end.

That Apache has collector value…I would leave it stock…Out in New Mexico, on the Apache Reservation, they bring SERIOUS money…They have become a HUGE status symbol…

The fancy models with two-tone paint and the wrap-around back-light, name your price…