1980 cutlass calais engine swap

[Guest]

Hi all I am new here and just wanted to post a quick question, I have the oppurtunity to buy this car for $300.00 and it is really good condition inside and out. no rust or serious body damage (3-4 small hail dents). but the question is that the 350 that is in it has the rods knowcking. I have a 455 olds out of a 196? or 1970 olds 98, and was told that it will fit right in without modification. is this true? I dont want to take a few weeks of evenings on this thing to find that I sould have just overhauled this old 350. I am a power junky and this would be a perfect combo, if it will work. so if you have heard of this please let me know

thank you I forgot to add that this car has a turbo 350 trans. I have read here that I will need to shift kit it to keep it from dropping top the ground when I stomp on it. is that true

Dwayne

[rocketraider]

If the car has an Olds 350 the 455 will drop in on the same mounts but is wider and a bit taller than the 350. You'll be limited to stock exhaust manifolds and a 3" tall aircleaner due to clearance issues. If there's a Chevy engine in there things get more complicated.

The 1980 car uses a radial A/C compressor. The brackets will bolt to the BB but you'll have to experiment to get the right length belt. Use the BB brackets on the other components and get belts for the 455 application. 350 hoses should work OK.

If you decide to stay on the computer you may get into some sensor location issues, but most guys doing this swap don't worry about it. Some 80s had it, some didn't.

As far as transmission goes, make sure you have a T350 transmission. Many 1980 cars had 250C metric transmissions which will have "metric" stamped into the pan and are junk. A turbo 350 will stand up to a lot of abuse but wouldn't hurt to beef it up a little for a big block. Also- you sure this car has a 350 engine? 350s came only in 442 and Hurst/Olds in 1979-1980, but those were based on the Calais. I'm betting the car has an Olds 260 or Chevy 305.

Check realoldspower.com or oldspower.com for more info, lots of folks on there have stuffed BBO into G-cars.

[Guest]

Thank you for the help...I looked a bit harder and ran the numbers (the info sticker is long gone) and found that the car has a 4.3l olds in it, but I did find that it does have the th350 trans (no metric stamped into the pan) I tore the engine down a bit today, all looked really good untill I got to the pan, when I removed it I had a lot of small (and some large) plactic pieces in the pan. Do olds 455 use plastic timing chain tensioners like a chevy 350 or 2.8? or what else can be plastic? thanks again for the help

[rocketraider]

What you've found are pieces of the OEM nylon-faced aluminum timing gear that broke off and ended up in the pan. Not unusual on an engine with more than 80k miles. Odds are you also found really worn timing chain and gears unless it's been replaced. If there's steel cam gear it's been replaced. Never understood why GM was obsessed with those nylon/aluminum timing sets. I've been told it was to reduce noise, but I can't stand beside two cars, one with nylon and one with steel timing gears, and hear any difference in engine noise.

A 455 will drop into a 260 (4.3l) car same as if it had had a 350. 260/307/330/350/403 are small blocks in Oldsworld; 400/425/455 are the big guns. All 64-later Olds V8s are same width at the oil pan/lower block area so they'll drop right into any chassis originally equipped with an Olds design engine, but the bigblocks are wider and taller in the deck and heads area. With that in mind, you may run into heater box and hood clearance issues with a 455 in the G-body car. Nothing insurmountable, just takes a little more planning is all.