Texas Jim

I'm currently making plans to install my '71 455ci Olds engine into my girlfriend's very clean '85 Cutlass Supreme. Obviously a joint venture. LOL! Just inquiring if anyone has done this swap, as I'm wondering what kind of room I'll have in the engine compartment. I will be using headers (w/ full 2 1/2" exhaust and Flowmaster mufflers), a modified 2004R transmission, and also keeping the factory air conditioning. Any info is greatly appreciated. Thanks in advance, Sincerely...

droptopron

A lot of G-Body guys post on Oldspower.com. It s a pretty common swap but i have no 1st hand experience with it.

svnt442

If the car came with a 307 it's a snap, but from what I understand there are some things you will have to do to make the A/C function. For some damn reason GM decided to have the A/C work through the computer and if you disconnect it it won't work. There is a way around it I believe so don't fret too much.

finman04

If you use anything but the stock or performer intake you might have hood clearence issues. The other problem is headers. Hooker sells a two pcs set for around $500 or Dick Millers for around $800. Having the same problem, droping in a 69 455 in my 79 olds.

panther80

My son and I are currently working on a similar project....Putting a 68" 455 olds into a 1987 cutlass 442..It will fit using your 307 engine mounts,assuming that your friends cutlass was or is a V-8 car...Will need a low profile intake manifold,such as a toronado intake,for hood clearance issues unless, you plan on cutting a hole in your hood and then installing a hood scoop or taking it a step further by ordering an aftermarket cowl hood ..Headers my be a nightmare unless they are custom made...(We may be using the stock manifolds on our project)...Oh...It will work with the 200r4 tranny, but if you plan on running it hard(it will be a challenge not to),You will need a reputable transmission repairman/shop to beef it up to handle all that torque that the 455 has to dish out...

Texas Jim

Thanks f/ all the input. The car does have a V8 in it, from the factory, it's all original. I figured I'd have to go w/ a header kit of some type f/ this engine/car, but that's ok, I can deal w/ that. I didn't know about the A/C being linked into the computer. I'm getting rid of any and all computers and going w/ all mechanical gauges, etc. (going w/ aftermarket gauges that fit into the original gauge holes.) If need be, I'll install an aftermarket A/C unit as well. Here in Texas, A/C is a needed option in a car, unless you're a "hardcore performance guy" or when it's pertaining to one of your "strictly performance cars." I'll also be installing a 9" Ford rear. I'm not building a car that will spend alot of time at the (drag) track, but want a strong street performance car that's also comfortable enough f/ my girl. I personally hate an American V8 equipped car that can't enter a hi-way via the entrance ramp w/o being run-over by 4cyl. imports. Any more info would surely be appreciated. Thanks in advance.

Intragration

The computer harness comes through on the passenger side of the firewall, and contains some wires that relate to AC and I believe cruise control also. Pretty much everything else comes through the driver's side. I yanked the computer harness, if it ran on that harness, I didn't use it. Easiest way to pull it is to snip the wires as close as possible to the firewall on the engine side, and then pull it through from the interior side. Then plug up the grommet hole. Very clean, no need to pull the inner fender.

I'd recommend doing the swap and getting it running first, and then do the gauge swap if you intend to do this. The Edelbrock performer will fit fine, Toronado intake is unnecessary, I have about a 2" or so open-element air cleaner on top of this, and it just fits. The passenger side valve cover could potentially be an issue on the AC box, if you can get notched or otherwise clearanced covers (i.e. '74, I believe, "Oldsmobile" script covers) it might save a headache. Not 100% necessary. Hooker 3203s work great, excellent fit, even with stock starter. It's not that close, don't listen to the people who say you've gotta go with a Ford remote solenoid. I recommend running the wires to the starter along the front of the block, down, and straight back to the starter, instead of from the back down by the headers. When putting the motor in, lay the headers in first, and lower the motor on top of them. It may seem like it's not going to fit, don't worry, it just takes a little coaxing. You'll need to notch the trans crossmember or get something that is already clearanced for the headers, the driver's side dumps right into the crossmember.

Having said all this, it really does fit as if the factory intended it. Enjoy.

Rickman48

Having installed Hookers and straight duals on a '80 Malibu, I can tell you from expierence 64 - 67 A-body rear crossmembers give you a 'double-hump' with a little modification and drilling!
Even the E-brake worked, with ajustment!