View Full Version : 84 Cutlass Supreme Engine Swap
12-30-2000, 11:03 PM
I have an 84 Olds Cutlass Supreme Brougham with a 2.? V6 or is 3.?. It doesn't really matter since I'm going to yank it anyway. I recently purchased a Chevy 350 bored .30 over. The 350 has a .510 lift cam, double hump (camelback) 2.02, 1.60 heads that have been ported and polished and shaved for 9.1:1 compression, Performer Intake, Holley 750CFM Carb., Edlebrock fuel pump, high volume oil pump, deep dish oil pan,hugger headers, Accell Super Coil, rotor button and wires. Est at 420hp. I have a THM350 with a B&M Shift assist kit and a 2800 stall converter.
My question? What motor mounts will I need? Tranny mounts? Any accessory mounts(ie: power steering)? I know the present A/C compressor will have to be moved or replaced and I am replacing the 2row 20" radiator with a 4row 28" and adding a tranny cooler.
I'm sure some of you have done a V6 to Chevy V8(350) swap. Any info you can give will be greatly appreciated. I will keep a picture record of the swap when I start removing the V6. Hopefully that day is very near.
Thanx in advance!
12-30-2000, 11:37 PM
Get the motor mounts for or from a 84 Monte Carlo with a 5.0L V8. I got new once from GM at the local GM dealership parts department. you need the frame mounts and the engine brackets. Use the same trans mount from your V6 trans. The trans is the same length and shape as a TH350. The P/S pump is the same pump they use on the Monte Carlo or any chevy small block since the 70's. So get the P/S pump brackets from or for a SB chevy. If you wanna use the AC then once again go to the Monte Carlo setup. Get the hoses and brackets for the Monte Carlo. You're basically turning your Cutlass into a Monte Carlo SS so things like radiators and radiator hoses are the same. Any thing else you're worried about? Ask me, I've been there.
1983 Oldsmobile Cutlass, 3.8L V6 and THM250c (yanked July 30, 2000). Getting ready to drop in a 383 stroker and a THM350 with a homemade shift kit (I know its a Chevy motor, but oh well. Actually I got it in finally Aug. 26,2000 ). 383 Stroker specs: 4-bolt mains w/ ARP main studs, Scat crank, stock 5.7" rods w/ARP wav-locs, .030" over, 9.6:1 Comp ratio, Trick Flow heads, ARP head bolts, Summit roller rockers, Comp cams 268H (268 adv. duration, .454" lift), Hyperuetechtic pistons, Flowtech Afterburner headers, Edelbrock Performer intake, Mildon high flow water pump, and fluidamper balancer.
12-31-2000, 12:46 AM
Thanx for the info 83Cutlass. I knew someone had made this swap before. I'll probably have more questions as I get more into it. Did you swap the radiator and R U using a mechanical or electrical fan? The shroud.. uhh.. from a Monte Carlo SS Right? Did you have to make any mods to the rear end? Suspension? I have too many questions.. I just want this to go as easily as I can. If I'm prepared, then it should go ok. I'm going to do this in the driveway (carport) by myself. I've done swaps before (30+ years ago) and we just ripped, cut and welded whatever was in the way or needed for the fit. A 327 into a Hillman panel truck. A 389 into a 54 Ford Victoria. A 327 into a Datsun B210 (that one was fun). So I'm not really new.. just older and a little wiser (I think).
Thanx again for the info. I'll get the Monte Carlo stuff next week.
See the car and new engine at
12-31-2000, 08:27 AM
I got a brand new radiator form GM for a Monte Carlo SS. Fits perfectly. I haven't found a fan shoud yet but I've looked. I think a fan shoud from any V8 G-body would fit. I'm using a mechanical fan. I haven't done anything with the rear end or suspension but I will be replacing the springs. People told me I'd have to replace front springs for the added V8 weight but my car isn't really sagging so I can hold off for a while. I also did my swap in my drive way. I found it easiest to remove the hood and pull the engine and trans out still connected at the same time and install the new engine and trans at the same time.
I took a look at your web site and have to say I'm very jealous. My Cutlass isn't quite as clean. Mines brown and the only rust you can see is the rear bumper. and man is it ugly. The bottom of the doors is rusty to but you can't see that form the outside. the headliner is sinking downa little in the rear too, but thats easy to fix. By the way from the look of the engine it looks like a 3.8L buick V6. Just like mine was. Thats good because the wiring harness on the drivers side fits perfectly on the V8 chevy. the Alt and starter are on the same side and the wiring reaches both very well. Easiest swap ever!
12-31-2000, 11:40 AM
83Cutlass, Thanx for the Kudos on my Olds.. It really is in very good condition. I have e friend with a body/paint shop that is getting me a radiator and a set of Olds wheels. I plan to get the car painted with the "Olds Mags" to match. Right now, I'm concentrating on getting the engine done. I'll clean up the "bay" while the motor is out. I too plan to pull the engine and tranny together. With the radiator out this should not be a problem then slip the new engine/tranny combo into the bay as one unit.
My biggest hold back right now is the weather.. It's 25 degrees in the driveway right now.. too cold to even change the oil. Sure hope I get some 50+ deg weather soon.
I'll keep ya posted and my webpage updated with the changes. I'll also remove some of the car pics to make opening the page a little faster. I don't notice the Slowness with this cable connection.
01-02-2001, 09:36 AM
Good luck on the swap! I just finished a 3.8 v6 to Chevy 350 swap this summer. I kept a diary on the "What's New?" Section of my website that you may find interesting.
Like 83Cutlass said, just go find a donor car and grab all the brackets off of. For my radiator I just bought a 27" one and then grabbed a shroud off of a 305 Impala or something like that. When you go to the auto store to get your radiator hoses and everything just tell them any G-Body with a 305 (A Monte SS should do just fine).
The tranny mounts should not change. Your only problem may be running true dual exhaust. I am not sure how the tranny crossmember is setup in your car but in my Buick it had to be heated up and banged a little to produce a driver's side hump to accomodate the driver's side pipe.
Between 83Cutlass and I this swap should be a breeze. I also scanned in tons of pictures on my site that may help you also.
1984 Buick LeSabre Limited (Chevy 355 powered)
Edlebrock, Hedman, Weiand, Crane, Taylor, Moroso, Autometer,
Cloyes, Clevite, ARP, NGK, Federal Mogul, Summit, Melling, Bell,
Kenwood, Crunch, JL Audio, Pioneer, Sony, JVC, Carbine, Motorola
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