autofluencia

Hey guys just looking for some help on a swap im stuck on. Doing a 394 to 455 swap

joe_padavano

Stuck how? By now you know that the 394 and 455 are completely different. You need to fabricate frame mounts to mate to the later 455 motor mounts. You'll also need to adapt a conventional trans crossmember since you can't use the bellhousing trans mounts on a later GM transmission.

autofluencia

Yes, I'm playing around with location of the engine. The mounts are not the issue I know I'll have to redo those. however, I'm dry fitting the 455 and I'm having interference issues with the exhaust manifold and the steering box, the stock cast ones turn downwards right at the steering box causing a crash. I have stainless tubular manifolds but they also wont fit because they flare out and crash into the steering box also. I was searching online and I cant find anyone that has done one of these. My main issue is that I was told by a very famous olds shop that it would be "bolt in" and either its not a bolt in or Im not catching something. If someone out there has done the swap I would like to know if they experienced this issue.

redoldsman

I think you have to mount the engine slightly off center to the right. I believe I have read this before. I think this is what citcapp (Pat) had to do on his 57. I imagine he will speak up.

autofluencia

I'm hoping he see's this soon because I'm really close to running with it. The way I have it mounted I could make a new manifold that goes straight back on the drivers side and be done with it. On the passenger side I could dive in and take a swim. I really like the position right now.

joe_padavano

Whatever shop you are talking to is flat wrong. The only "bolt in" option would be the 1964 Jetstar 88, which came from the factory with mounts for the 330. The 394 cars do not have the welded-on plates on the frame that the J88 does.

As for exhaust manifolds, you need the repro B/C-body LH manifold sold by Thornton. It's designed for the 1965-70 cars, which also have the rear-steer linkage and box location, but it is the best you can do for the 63-64 cars.

autofluencia

I found that out pretty quick.

As far as that manifold goes, this is tested and proven? I went through 3 different sets of manifolds already.

autofluencia

After some digging around a bit with your suggestion, I'm going to wait and get this manifold before I reattempt to mount the engine.

70cutty

I don't know about the manifold but I can tell you one thing, if Joe tells you it's gonna work, it's gonna work.

autofluencia

Thats great! hahaha Ordering this Monday morning.

redoldsman

This swap is 180 degrees from a bolt in. There is a ton of fab work involved.

citcapp

i believe you will have to off center the engine at least 1" to the passenger side of the car to clear the steering box . I used the W/Z Thornton headers for the 455 on my conversion and they cleared the steering box. There is plenty of room on the passenger side. Here is a picture of what I did on the 57. Yes there us a lot of fab work but not overwhelming. Just takes time. Other things i did where

1. replaced the two piece drive line with a single piece drive line. I did check out converting to a chev truck two piece drive line and that would be doable as well
2. Converted the column shift to work with the linkage off of a 75 chev pickup. I used a turbo 400 transmission.

autofluencia

That's really helpful, I saw that it clears better if I moved it over. In all honesty, if this manifold clears the top of the steering box there's little shift over to the passenger side.

It has so much room, for the Trans mount. I'm using a u shaped crossmember for the front mounts. Not to many places to go to on the frame for the front.

joe_padavano

The manifold I posted a picture of is a reproduction of the factory dual exhaust manifold used on the 65-70 B/C-body cars. While the frame on these cars isn't exactly the same as the one on the 63-64 cars, they do have the steering box in the same place and the same rear steer linkage design. That's why the manifold has that unusual shape - to get up over the steering box and the column shift linkage. This is the ONLY factory manifold for a BBO that is designed for this application in the full size cars. I'm guessing all the other manifolds you've tried were from applications with either manifolds from front steer cars like A-body cars or from single exhaust applications where the driver's side manifold has a center dump. That latter will only work if you plan to run a single exhaust with the crossover pipe to the passenger manifold. I'm sure that's not what you want. There should not be much engine offset required with the Thornton manifold. (Note that I am not talking about the Thornton W/Z manifolds, but what they call their "Starfire" manifold.

autofluencia

Parts have been ordered as of today, should be getting it in late this week. thornton gave me a 2-3 month wait on it, we were able to source it from Fusick automotive. Lets see how it works for this.

autofluencia

Got the part in from Fusik. It fits like a glove. It goes up and around the steering box just like you said. Thanks for pointing me in that direction joe-padavano. I will post up pictures when we are all done here.

joe_padavano

Great. I'm glad that worked for you.

autofluencia

Here are a few pictures of what I did for mounts/fitment. And how the manifold fits.

autofluencia

Here are some pictures of the modified mount that Mondello sells. I had to extend and play with this mount because it sat lower on the drivers side and clearing the steering box was no easy task. It sits just about 1/2" in forward of the box.

autofluencia

This is my first Oldsmobile build and I have a few questions. Any info would help out. I got this project in boxes, literally. I am not sure about the fuel pump and some of the vacuum lines on this. I will post up pictures of what I have in question as I get stuck on them.

For starters:
-Which way do the weights face on the flexplate installed?
-there are 3 nipples on the fuel pump, the one that says "in" is self explanatory. the other two not so much. There is a big and a small nipple where do these go?

Thanks for your reply!

joe_padavano

The crank flange has one of the six bolts offset. The flexplate will only bolt up in one orientation. If it's flipped, you won't get the bolts aligned.

The large outlet port goes to the carb. The small one is for cars with fuel return. If you don't have fuel return, just cap it.

joe_padavano

Here's another tip. Those notched valve covers are unique to the 1968-72 big block A-body cars, and the notches go towards the back to clear the power brake booster and the A/C box on the firewall. If you don't need them, sell them to an A-body person and pocket the difference from standard valve covers.

autofluencia

I'm working on the car for a friend. I'll let him know about the valve covers.

Interesting thing is going on with the flex to torque. I have interference with one of the torque converter ears and the flexplate weight. Its only about a 1/4" interference. These are equally spaced so I cant spin it to a different direction. I'm going to have to notch that guy to clear the weights. That was the basis for my last question about direction.

Wedgewood Rod Shop

What engine motor mount setup did you decide to go with?

Octania

Oh, I relish the day I can spot an error in a JoeP post!
TWO of the bolts are offset from a perfect hex for 1968+
ONE for 1967 and back, the other direction.
End result- you cannot put the flexplate on backwards.

As for the fuel pump, the threaded fitting is pressurized fuel to the pump.
The large 3/8" nipple is suction inlet from tank.
5/16" nipple is return flow, as JP said, cap if unused.



Interesting thing is going on with the flex to torque. I have interference with one of the torque converter ears and the flexplate weight. Its only about a 1/4" interference. These are equally spaced so I cant spin it to a different direction. I'm going to have to notch that guy to clear the weights. That was the basis for my last question about direction.
============================
Which part is non-factory?
The TC I am guessing. Can you grind the offending part away?

droldsmorland

Are you sure the converter is correct for Olds flywheel? Most in the un-no will sell you a chevy converter. I assume your using a BOP TH400?

autofluencia

My buddy supplied a Mondello crossmember that I had to cut the ends off of. and extend both sides at the U shapes. You have to drop the steering box and float the engine on stands or a lift and play with it. I used the fan to guide the position of the engine. There's not that much room to play with since you have to clear the steering box on the drivers side. for trans mount I used schedule 40 pipe and made the mount.

autofluencia

Thanks, I ended up spinning the TC to a position that had less interference with the weight on the flexplate. I took a small corner off (1/4") of the weight on the TC and it fit good after that. The TC was supplied with a rebuilt unit from Mondello. We are still trying to figure out a shifting problem with the unit they provided. Looks like it was a bad unit.

autofluencia

Converter came from Mondello.

blakes7

What was wrong with the 394? If it's still good, are you interested in selling it?

autofluencia

Ran fine, no weird noises or anything. Actually we were going to put it up for sale soon. Have video of it running. Email me at mario@autofluencia.com

Wedgewood Rod Shop

Great, thank you. Did you have to drop the gear box to allow yourself room to weld in the crossmember? I have a few more questions if you don't mind providing some insight.

what exhaust did you decide to use? Manifolds or headers? Any advice in that arena?

Did you have to modify the trans tunnel?

Wedgewood Rod Shop

Sorry, I just scrolled through and found that you went with the thornton manifold. Did you end up having to shift the motor over at all?

Wedgewood Rod Shop

Are you aware of any headers that will fit this application?

autofluencia

No problem, The gear box has to come down because the crossmember I used was a tight fit and it interfered with one of the ears of the steering box. I also cut off a piece of the box that interfered with the fitment. You will have to play with it.

You can use the stock manifold for the pass side, Thornton on the drivers. This setup was the only one that worked for me. The headers we tried installing would not fit because of interference with the steering box. As big as this car is there is very little room to play with. You will have to raise the car in the air about 18" and float the engine and trans in there while you make adjustments to the position of the drivetrain.

autofluencia

No mods to the tunnel, and no significant or substantial shift to pass side.

Wedgewood Rod Shop

Great, thank you, I appreciate the information. I just contacted both Thorntons and Fusick and they are both out of the necessary driver manifold and said it might be months before they have inventory again. I am going to be stuck on that one. Do you know any other sources?

Also, do you think the 63 Jetstar you are completing and my 64 Ninety Eight are identical conversions? I generally build chevrolet and this is my first olds as well.

autofluencia

Mondello has it but its more than twice the price, if you need it you will have to give up a kidney. I got the same answer from them. There are used ones that i recently found on Ebay. you can scrub and paint it with High heat paint. I ended up having to do that on the fusik one. It was coated with something that flaked off real bad when it got hot.

I'm not sure about the cars, this too was my first olds. Some of the guys on here could probably chime in on differences in chassis.

Wedgewood Rod Shop

Would you have interest in making another transmission crossmember that I could purchase from you?

Wedgewood Rod Shop

Okay, thanks. I will check with Mondello as well, but won't be excited about paying the premium. I tried ebay, but I am either not searching the right key words or there just aren't any on the market right now.

I just replied to another one of your posts, but I would be interested in purchasing a built trans crossmember if you still have the specs and would want to build a second one.