69cutlassolds

Hello
Thank you for taking time to read this. I am a newbie to this forum, so pardon if I have this posting in the the wrong category.
I have a 1969 Cutlass convertible with it's original 350 engine, it runs, but is in need of rebuild, having a weak cylinder.
I've had the car for several years, and have had the notion of swapping out the 350 for a 455 to gain more torque and some HP, and some time ago had acquired a 455 in pieces, a .030 over rebuild kit, and TH400 which I had rebuilt.
Just this past week I came across another 455 out of a 1973 Delta 98 hearse, that had only 49,000 miles on it, this motor was/is complete with everything ready to drop in the car, including a TH400 attached and it's 4 barrel carb'.
So here is/are my questions.
It's a "J" head motor, yes I know, but this car is not going to the race track, my plan is to put a set of Headman headers on the car and a dual exhaust.
Do I need to change the radiator from the 350 to the 455? I live in Ohio, and put less than 700 miles a year on the convertible.
And, from anyone who has put a 455 in a 1969 Cutlass, any tips, and suggestions would be greatly appreciated.
Again, my intention is only to have a car that will stick me back in my seat more, not to build a ground pounding torque machine, ( not that there is anything wrong with that ) having hardened valve seats is good, so, I am good with the J heads, at least for now. I would add, this is a budget build so you can understand a bit more where I am coming from.

Thank you.

oldcutlass

The 455 will basically drop right in. The T400 will require some minor changes to the Ebrake with the moving of the transmission xmember back a few inches and of course modifying or replacing the drive shaft and yoke. As far as the radiator, I'd see if your current setup will suffice before going through the expense of an upgrade. As there is about 80#s difference in weight you may want to consider going to a heavier front spring if your old ones are weak and sagging already.

69cutlassolds

Thank you Eric, I appreciate your reply, was aware of the driveshaft and yoke, but forgot to mention it, I was wondering about the springs, am having Right Stuff disc brakes put on, and balljoints, tie rods and control arm bushings.

Nice 1967 you have, how did you set up your 400 kickdown?

oldcutlass

I haven't messed with it yet to be honest, manually down shift if necessary. I was going to use the stock switch from the throttle linkage but its worn out and inop. All you need is an aftermarket switch at the carb set to wot to make it function.

joe_padavano

Welcome. The one thing you need to know is that the 350 and 455 Olds motors are externally identical EXCEPT for the deck height. That means that motor mounts, bellhousings, water pumps, etc all interchange. Any external part that ISN'T affected by the deck height difference swaps. That makes this very easy.

The taller deck height does affect the exhaust, which is why you need different manifolds or headers. The starter is physically the same, but the 455 uses a high torque version, which is a smart investment. The radiator needs to be changed. Don't risk your new motor. Obviously the taller deck height requires a wider intake manifold. Flexplate swaps with no problems.

There are three different height water pumps for Olds motors, but the difference is based on optional equipment (such as A/C or HD cooling), not on the engine size. The accessory brackets, pulleys, and pump all need to be used as a matched set, however, to assure belt alignment. Swap everything from the 350. The accessory brackets will have two sets of holes where needed to accommodate the taller deck. Obviously the belts change as the accessories get further away from the crank. And pay very close attention to the two spacers between the power steering pump bracket and the block. Be sure they go back in the same places on the 455 or you'll be writing a question about belt squealing or alignment problems.

The one thing you should not change is the motor mounts. DO NOT buy "455" motor mounts. The rubber mounts need to match the frame mounts, not the block. If you need new mounts, get the correct replacement mounts for your 350 (Anchor P/N 2261) and bolt those to the 455.

Good luck.

69cutlassolds

Thanks Joe I appreciate the info and time taken, the 455 came with all it's brackets, so I'l just use all those, except AC, will need a different length belt since deleting AC.

svnt442

Use the Cutlass brackets and pulleys with the water pump and power steering pump off the 350. That will make things that much easier down the road. The power steering belt is the same and you'll just need the longer alternator belt for an A/C 400 cutlass/442.

69cutlassolds

Thanks Randy, I appreciate the info and your time taken to respond.

joe_padavano

Go back and read my post again:

69cutlassolds

Joe-
Is this a height issue? As I mentioned, the 455 is complete, as in brackets, pulleys, pumps, everything, it is a complete set. In that the 455 is complete I don't understand why I need to switch from one complete set ( 455) to the 350 complete set. I will be changing out the water pump, but will note the advice and be sure to get one that has the same height/length as to what is on the motor now to maintain alignment.

thank you.

joe_padavano

If the 455 set is complete, then it should be identical to the brackets on the 350. I was confused by your earlier post about "except A/C". I took that to mean the A/C bracket was missing and that you might be taking that one from the 350. If you mean you are deleting A/C, you need the non-A/C brackets that move the alternator to the passenger side. This also uses a different length water pump, or different pulleys if you have HD cooling. Again, this is why, for the novice, it is easiest to just keep the factory parts together as a matched set. The issue isn't deck height, it's the length of the water pump and the need for the brackets and pulley offsets to match that.

69cutlassolds

Again, thanks Joe.

69cutlassolds

Doe anyone know of a source of pre-bent with fittings fuel line set for the 1969 Cutlass preferably in 3/8" diameter?

Thanks.

joe_padavano

Inline Tube, Right Stuff, etc, etc. Be sure you get lines for a 1969 442 with a big block and not a Cutlass with a 350.

69cutlassolds

Thanks Joe, I'll check out Inline Tubing, Year One only has bulk tubing and fittings, no pre-formed lines.
Do you reckon 3/8" diameter is adequate for a 455ci?

joe_padavano

That's all you're going to find in a pre-bent line. Anything larger you'll need to fabricate yourself. If you were running a high-HP, custom built motor, you might want to consider a 1/2" line, but for a close-to-stock 455, the 3/8 will be adequate.

69cutlassolds

Thanks again Joe, as always I do appreciate your information.

Dave