JPinAZ

Hello. My name is John and I am about to take on a big project for a customer. His one owner 1977 Cutlass 442 is all original. 300K+ miles. 260 V8 5 speed MT. Highway gears in the diff but I can not remember the ratio at this time. Rare car but not sought after. We will be putting in a 455 and another MT trans to be determined. We are not looking to build a race car, the 455 upgrade will be plenty. Recently we replaced all of the coil springs with 455 springs and the brake/master cylinder with a Bendix booster. Now the hunt begins to find everything else we need and what we can reuse. I have read a lot about this swap and some of the "problems" that can occur but I think that was mostly 68-72 and not the 73-77 model. TIA, I will post questions in the correct forums soon.

joe_padavano

I'm not sure what "problems" you've heard about, but the 455 was factory installed in the 1976 cars, which are identical to that 1977. Obviously the T50 trans currently in it won't live behind a 455, but the fact that the car already has the clutch linkage is a great start. Be aware that the 1973-76 FA 455 blocks typically do not have the hole for the Z-bar pivot machined. Other than that, the engine is a bolt-in. Use the existing motor mounts and frame pads. Get W/Z exhaust manifolds or headers. You'll need a double hump trans crossmember for dual exhaust. And of course you'll need a larger radiator.

JPinAZ

Thanks for the reply and info. I guess other than what you mentioned the #1 "problem" is will I need the A body valve covers for AC and power brakes? #2 MT crankshaft.

joe_padavano

The larger 73-77 cars do not require notched valve covers on the big block. Yes, you will either need an MT crank or will need to have your current crank machined. That's not unique to the 455, that applies to all 1964-90 Olds V8s.

JPinAZ

Thanks Joe. This is why I joined this forum. I would never have been able to do my 71 GS clone project without V8Buick.com. I need real info for the 73-77 cars. I knew the crank could be machined and your specs are a great help. What every we end up with will be at the machine shop anyway. Mods, sorry if this it to much for the newbie forum.

69CSHC

There it is, just mentioned in another thread how the 260 just keeps going and going....

I believe 1977 is the last year for the corporate 10 bolt 8.5 in Cutlass and the gear is likely a 2.73. If that's the case the rear can handle a 455 just fine. With the additional 150 FT LBS of torque minimum the 2.73s wont seem bad at all either. Even with a base 1976 455 swap, it should be a night and day improvement in acceleration.

Exciting stuff, i'm sure the owner is psyched. Please keep us posted on how this turns out.


P.S. if he drove the 442 as is and thinks it moved half way decent. Get ready to see the biggest ear to ear smile when all is said and done.

1977 442 260 5 speed 0-60 in 14.9 seconds, 1/4 mile 20.6 seconds

1973 442 455 4 speed 0-60 in 7.0 seconds, 1/4 mile 15.5 seconds

Automobile Catalog simulation

KW5413

With the '76 & '77 being so similar, I don't know if this helps at all but, my '76 w / 350 was born with a 2.41 anti-spin...Not sure if this was a option or part of the Salon package.


It now has a 3.08 posi...complimented with a 2000 stall converter.