UTfan01SS

iTrader: (1)

I bought a nice 85 cutlass to build into a street/strip car with plans on throwing the 307 in the trash and building a chevy 355. Does anyone know if the accessory bolt holes are the same on the heads? I'm thinking they would being a GM car but I'm not 110% certain so I'd like to know for sure before I go dropping money into the engine build. Now the car has a TH-350 and that all bolts up the same too correct? Thanks

ZONES89RS

iTrader: (25)

Damn, a friend told me a while back what was needed but i cannot remember, was just the mounts i think.

9000th01ss

iTrader: (10)

The accesories will bolt up with the oldsmobile brackets, meaning alternator, PS pump, AC comp.
The th350 Could very well be a universal case that will bolt to a chevy or a BOP (buick, olds, pontiac)
If not, it's BOP only but will work on a chevy with an adapter plate.

87silverbullet

iTrader: (11)

Nope, nothing will bolt up the Olds 307 is a total different motor design from a sbc. The trans will only bolt up if it has the universal bell housing which is rare. Just junk the whole motor its not worth anything. The stock compression on that motor 7.9 to 1. The stock cam doesn't even go over .400 lift. I remember this because I looked this stuff up when I worked at the dealership and I had a 1984 olds delta 88. Just buy a nitrous plate system and spray it til it blows. With the low compression it will not have as much cylinder pressure spike and will handle a nice size shot.

1997bird

iTrader: (2)

The 307 engine in your car has the same bore as a 283 (3.875") and the same stroke as a 327 (3.25"). The crankshaft has the same main bearing diameter as a 350 and is a easy swap to be able to build you a 327. I would hold onto the crankshaft for trading material or maybe a future build. The bellhousing is the same bolt pattern as a standard SBC, they quit producing the BOP tranny's after GM incorperated in 1976 (in some models it took up to I think 1983).

UTfan01SS

iTrader: (1)

So could a person bore out this 307 and get some good cubes out of it? I have never worked on nor owned an oldsmobile so I dont know anything about them. I was reading on a G-body site that the 350 rocket engines make great power but it seems hard to find em. I would be interested in building a big block olds but those seem to be rare as well so I guess I'll stick to a SBC. Can't beat them for the money and performance. Does anyone know where I can get a complete used Big Block Olds? 455ci, 400ci? Now, one more question. What is the difference between a Pontiac big block and an Oldsmobile Big Block? Would a pontiac 400 SB or 455 be a direct swap meaning the accessories would bolt up? Thanks for the help, I'm learning alot about these.

1997bird

iTrader: (2)

If you are wanting a big block then I would go with a BBC. The Olds big block would be easier to retro fit than the Pontiac(the headers are a major PITA x2). I would just stay with a SBC for ease of finding parts in the aftermarket world. You can stroke the 307 for more cubes, but you will have to buy a set of custom piston's. The largest stroke that I have heard of in this block is 3.85", which would give you 375 cid with the block bored .060" over. With the proper set of heads (for the smaller bore size) and a hydraulic roller cam you can make 500 HP at the flywheel.

87silverbullet

iTrader: (11)

Anything about olds motors, you need to check out Joe Mondello he is Mr. Oldsmobile.

Anything about pontiac motors you need to take a look at Butler Performance.

I also recommend staying with a sbc you can build so much with it and parts are readily available and cheap.

UTfan01SS

iTrader: (1)

Yeah from the research I did yesterday I decided to stick with the SBC and ditch the Olds idea just because the Small Block Chevy is hard to beat for price vs. HP. It seems hard to find an Olds rocket 350 or big block and even the one's I did find were in bad shape with the price being too high. The plan is right now to go with the Northern Auto parts 350 master rebuild kit which comes all name brand parts. I'm looking into the ***** Thumper cam from Comp to go with the Trick Flow 23 SBC Aluminum heads I have at home. Hopefully this combo with a good Edelbrock intake and carb would net around 450 to the flywheel with the block punched 30 over. I'll be running a 3200 RPM B&M holeshot torque converter as well. Does this sound like a decent combo? I'm looking for great power, awesome idle while being able to drive the car with the A/C wide open during the hot summer car show months.