I've been wanting to swap out the 307 and 200r4 out of my 1984 olds Ninety eight for something with a lot more power, and I'm wondering what all motors and tranny's fit in this car without major modifications.
any info would help

 

I get that you're wanting more power, but what's wrong with the transmission? Easiest thing to do would be to swap in a '68-70 350 with a few more beans and leave the transmission be if it's in good working order.

But really, any Olds V-8 1965-up (1964 for the new-gen small-block 330) can be installed with a minimum of headaches. Many people also transplant small-block Chevies as they were plentiful in B and C bodies in 1984. But of course, I can't recommend that!

 

To clarify, any small block Olds V8 (260, 307, 330, 350,403) is a direct bolt-in. Use the water pump, accessory brackets, and pulleys from the 307 as a matched set. The big block Olds also bolts in, but is about an inch taller and wider. so there may be some clearance issues with the HVAC box. The taller BBO will require different exhaust manifolds, which means you will need to re-build the exhaust system. In either case, use 2328 motor mounts to match the frame pads.

The 200-4R probably won't last in stock form, especially if you decide to use the extra HP and torque of the new motor. The 200-4R uses the same crossmember location as the TH400 but is the same overall length as a TH350 A TH400 will bolt up to the current crossmember, but will require a new driveshaft. A TH350 requires a correct crossmember (on these cars you can't just slide the crossmember forward or back) but you can keep your existing driveshaft.

 

^^^ Joe, I note that you're kind of more down on the 200-4R than you used to be. Don't you think it would survive behind a 310 HP 350, especially with a few appropriate mods? My inclination would be to run it until some thing breaks and then when (if?) that happens, rebuild it for its intended use.

 

Yeah, given what it's cost me to build a couple of them now, and given the availability problems with some of the select-fit thrust washers, I'm more in the 4L80E camp. I drive my cars and would rather not have the trans break when I'm on a trip.

 

I like the 2004R, but it’s been probably 10 years since I messed with one. Parts weren’t very common then, I have no doubt it’s worse today.

It’s my opinion a 2004r will live behind a mild small block reliably IF you’re willing to do some minor upgrades. At the minimum, use a TransGo shift kit, CK Performance use to offer a package that included a performance cslibrated valve body, servo and govenor. No clue if that still an option today. And it should be obvious that TV cable adjustment is a requirement. “Close enough” ain’t good enough. The cable has to be right, or the trans won’t last.

if future plans are for a rowdy torquey big block, bite the bullet and go 4L80. You will wear it out long before you break it, parts are common, and getting cheaper all the time.

Buy once, cry once, then enjoy.