The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 55.2-59 What’s the most practical way to swap engines?

washington blue · 12-05-2018, 11:12 PM

A carburetor engine needs vacuum and mechanical advance to run it's best. Full Mechanical is at about 23-2600 rpm and full vacuum is at about 2000 rpm. Running the engine down the road slower than say 2300 rpm is not good for gas mileage and not good for the engine either. The reason to put an overdrive transmission in something is to get better mileage and less engine wear. Very hard to do with an overdrive trans hooked to a carburetor engine. The OP said he likes carburetors and he wants to keep the original suspension and he plans to drive around town and occasionally a few miles out of town. With this info a 700r4 would not be the best trans for him. Buy something like a 1975 Nova 4 door in nice shape and take the 350 engine and Quadrajet carb, th350transmission, driveshaft, and rear-end out of it and put them in the 56. Very straight forward simple swap. This way you have exhaust you might use and E brake cables and
lots of other little stuff too.

12-05-2018, 11:12 PM	#27
washington blue Registered User Join Date: Mar 2016 Location: Not far from Sioux Falls South Dakota Posts: 328	Re: What’s the most practical way to swap engines? A carburetor engine needs vacuum and mechanical advance to run it's best. Full Mechanical is at about 23-2600 rpm and full vacuum is at about 2000 rpm. Running the engine down the road slower than say 2300 rpm is not good for gas mileage and not good for the engine either. The reason to put an overdrive transmission in something is to get better mileage and less engine wear. Very hard to do with an overdrive trans hooked to a carburetor engine. The OP said he likes carburetors and he wants to keep the original suspension and he plans to drive around town and occasionally a few miles out of town. With this info a 700r4 would not be the best trans for him. Buy something like a 1975 Nova 4 door in nice shape and take the 350 engine and Quadrajet carb, th350transmission, driveshaft, and rear-end out of it and put them in the 56. Very straight forward simple swap. This way you have exhaust you might use and E brake cables and lots of other little stuff too.