'72 Vista Cruiser 455/th400 --- teach me please

[cts-v]

I bought a running 455/th400 out of a 72 vista cruiser to put in my 70 cutlass supreme. 72000 miles on the 455. G heads. Seems to be factory original down to the valve cover gaskets. My plan is to get headers, alum intake, and fresh cam and lifters to get it on the road.

My question is.... Is there anything special/ different/ unusual about vista cruiser 455s that I should know? Other advice about things I should check would be appreciated. I already sold my 350 long block, but kept most accesories, engine mounts, etc. Anything I should definitely check on these 455s?

Thanks. Tom

[J-(Chicago)]

Originally Posted by cts-v

I bought a running 455/th400 out of a 72 vista cruiser to put in my 70 cutlass supreme.
My question is.... Is there anything special/ different/ unusual about vista cruiser 455s that I should know?

Not really. 72 was a low compression year so it's probabaly around 8.5:1. A 68-70 motor would have had more
compression and HP. Around 10:1

Originally Posted by cts-v

Other advice about things I should check would be appreciated.

Your valve stem seals in the heads are probably dried out and cracked after 40 years of existance. You should replace them. While you're in there you'll probably have to wire brush 1/8"
of lead build up on all of the valves. Aftermarket head gaskets are thicker than the factory ones, so you may want to have the heads machined down to compensate. all of your 350 brackets and pulleys will bolt onto the 455.The motor mounts should as well. Just remember if you use the 350 brackets and pulleys, use a 350 water pump along with it so your pulleys will align correctly.

Be sure to replace the oil pump after 40 years as well. I put in a running 455 earlier this year and the oil pump failed after a month of driving it.

Get a new timing gear set and chain, the 455s have a nylon gear that is a piece of junk. I'd put a steel set in.

[joe_padavano]

Originally Posted by J-(Chicago)

Not really. 72 was a low compression year so it's probabaly around 8.5:1. A 68-70 motor would have had more
compression and HP. Around 10:1
Your valve stem seals in the heads are probably dried out and cracked after 40 years of existance. You should replace them. While you're in there you'll probably have to wire brush 1/8"
of lead build up on all of the valves. Aftermarket head gaskets are thicker than the factory ones, so you may want to have the heads machined down to compensate. all of your 350 brackets and pulleys will bolt onto the 455.The motor mounts should as well. Just remember if you use the 350 brackets and pulleys, use a 350 water pump along with it so your pulleys will align correctly.

Be sure to replace the oil pump after 40 years as well. I put in a running 455 earlier this year and the oil pump failed after a month of driving it.

Get a new timing gear set and chain, the 455s have a nylon gear that is a piece of junk. I'd put a steel set in.

Excellent advice. I would add that while the motor is out, install new front and rear main seals. Also, replace the front seal on the trans. (This is getting dangerously close to a MIGHTASWELL engine rebuild...)

[dan2286]

You might also want to perform a cylinder leak down test to determine the condition of the engine. All you need to do this is an air compressor and the leak down tester which should be at any parts store. This test will help you determine the condition of the rings, head gaskets, valve seals, etc.

[7244too]

Tom
One other thing you might have to consider is a different driveshaft? Also, did you get the motor mount pads off of the frame itself? It's not really a necessity unless your planning on going the W-30 look-a-like route. The 455 will sit just a little higher on the 350 pads. Not a big deal unless you go with the W25 hood and OAI air cleaner setup. Just complicates things a bit.
BTW, If that Vista is available for any other parts there are probably alot of members that would be interested. Just a thought...Gery.

[cts-v]

Hello all. Thanks for the advice. I'm going to have to start up a list of stuff to do so I don't forget anything.

One question about the engine mounts. If I use the 350 mounts, and the engine sets up higher, will my stock Cutlass Supreme hood clear the 455? Even if I switch to a Edelbrock performer intake?

Water pump? I thought these were the same for 350 and 455's. Both were originally AC engines, so I thought the water pumps would be the same?

FYI, my plan is to use my current TH350 and driveshaft for about a year. Next winter (if funds allow) either convert to manual transmission or go for new cylinder heads (then do the other project the next winter). Or do both in 2 years since the crank would have to be machined...

I bought the engine and trans earlier this summer. The guy brought back the wagon from Kansas I think. He wanted the car for a derby car, and only sold the engine/trans. Interior was gutted by the time I saw it. Unfortunaltely, the car is probably scrap metal by now.

List for my own benefit. A little longer than I originally thought. I better get to work with kid number two arriving in 3-6 weeks....

-leak down test
-valve stems seals
-clean off valves and heads
-water pump 350 or 455?
-oil pump
-timing set
-front and rear main seal
-trans front seal

-headers
-cam/lifters
-intake
-carb rebuild

[joe_padavano]

Originally Posted by 7244too

Also, did you get the motor mount pads off of the frame itself? It's not really a necessity unless your planning on going the W-30 look-a-like route. The 455 will sit just a little higher on the 350 pads.

NOOOOOOO!!!!!!

(Can we get the little head-banging-a-brick-wall smilie that they have over at OP?)

Once (yet) again: When used as a matched set (350 frame mounts with 350 motor mounts or 455 frame mounts with 455 motor mounts) EITHER BBO or SBO will sit with the crank centerline in EXACTLY the same place.

OK, I'll breathe now.

[7244too]

Once (yet) again: When used as a matched set (350 frame mounts with 350 motor mounts or 455 frame mounts with 455 motor mounts) EITHER BBO or SBO will sit with the crank centerline in EXACTLY the same place.

OK, I'll breathe now. [/quote]

Sorry Joe, my fingers were just flying over the keys but the brain didn't catch up! Sorry for the bad info on the mounts. Count to ten....OOOOOHHHHMMM

[cts-v]

Since the matched set of 350 eng/frame or 455 eng/frame mounts place the centerline in the same place, why did Oldsmobile use 2 different mount designs? Different isolation characteristics (different damping rates) or for clearance issues? Or something else?

I'll just reuse my 350 engine and frame mounts (so I don't have to buy the 455 frame mounts).

One more question... Does Autozone / Advance Auto Parts / NAPA carry good quality Olds engine parts (oil pump / water pump / valve seals/ front and rear main seals/ etc.)? If not, where to buy good quality parts?

Thanks for the great info. Tom.

[joe_padavano]

Originally Posted by cts-v

Since the matched set of 350 eng/frame or 455 eng/frame mounts place the centerline in the same place, why did Oldsmobile use 2 different mount designs? Different isolation characteristics (different damping rates) or for clearance issues? Or something else?

Actually, prior to the 1969 model year, there was only one design. The rubber mount design at that time was essentially two flat plates (with bolt flanges) with a chunk of rubber molded in between. The rubber eventually fractured, resulting in the engine torquing over and a jammed throttle. There was a major recall wherein GM added a steel cable torque strap from one of the exhaust manifold bolts to the upper control arm cross shaft.

To prevent this problem, Olds redesigned the rubber motor mounts so that the two metal parts actually interlocked. This way, if the rubber failed, the interlocking metal parts prevented the motor from torquing over. Note that GM also switched from a rigid throttle rod to a flexible cable, so that if the engine did move, the linkage wouldn't jam.

This redesign was rolled in over time. Olds started with the high-torque big block motors, so for the 1969 model year the 350 motor used the old design mounts and the 400/455 motors used the new design. The interlocking feature required the rubber mount to be physically larger, so the frame bracket was redesigned to accommodate it while not changing the location of the engine.

Starting in 1970, the 350 mounts were also redesigned to incorporate the interlocking feature, but apparently the engineers got smarter, as they were able to package the redesign in the original space.