I’ve found a 425 olds for sale. I currently have the original 330 in the car with the 2 speed transmission. The car runs and drives right now but I’ve been wanting more power and the 330 could really use freshened up. I found a 425 locally for $300 so I figured maybe a big block would be a better choice to swap in this winter than messing with the 330.

Il still keep the 330 as it is the original engine. My question is should I swap a 425 in? I haven’t found any 455’s locally. What is needed to swap a big block into my car. Just big block mounts? I see everyone talks about how narrow the frame is in the 64-67’s.

I was planning on pulling the 330 and getting the heads cleaned up, new cam etc, and swapping either a th350 or 400 in along with new rear ended gears. Is there a better cam choice for the 425 and would this be a good swap? I’m assuming the 425 will need rebuilt as it has been sitting since the late 80’s. It was rebuilt at that time the owner says.

My goal was to have the car sounding mean and being able to roast the tires when I wanted too as of right now that’s not the case. Which is understandable for sitting for 25 years. My car had been sitting since the 90’s so I just did a tune up to get it running and drivable for the summer while I worked on the interior before winter.

 

Great looking 64, but you will also have to upgrade the trans. The 2 speed just won't last.

 

The 400 or 425 or 455 is pretty much a drop in. You probably want to upgrade to a 65 style radiator as I believe the 64 water pump is a bit different... causing hose connection issues unless you use the 64 water pump.

 

It's not a game changer but you need to know the cam bank angle of the 425 before any cam changes. Toronado 425's are modern, 39 degrees as are all after 1967 Oldsmobile engines. In my experience, the seven 1967 425 engines I've had are all 39°. I've had two 1965, 425s both were 45 degree engines, I have four 1966 B-headed 425s that I believe are 45°engines. Your 1964 330 is a 45 degree engine with the early style rocker arms. The information is readily available as are 45 degree camshafts. So it's not a big deal but you don't want to make a mistake with the wrong cam bank angle. Jmo.

 

Whatever you do, do NOT use "big block" motor mounts. Keep the frame mounts currently in your car and use Anchor 2261 motor mounts. The 425 bolts in. You'll want BBO exhaust manifolds for an A-body or headers. If you use manifolds, the repro W/Z are your best choice. You'll need new accessory brackets, as your 64 brackets only fit an SBO. You'll want a high torque starter - your 330 starter is likely a low torque unit.

 

Everything I’ve read on the 330 is headers don’t really fit with the frame. Would they fit with a 425? My 330 has horrible exhaust leaks on both sides right now and I can’t get them off with the motor in the car. I was going to put some of those Thornton manifolds “short headers” on when I pulled it this winter. I already planned on switching the transmission. I just seen this motor so figured I’d see if it worth swapping in rather than rebuilding my current 330.

 

Echo these guys all good suggestions. I have a ton of pictures in my thread on the 64 F-85 build. I currently have a 67 400E with a modified 200-4R that is actually a Buick GN case-B 401. I also used 68 and accessories, a 3 core Champion radiator for 64-65 GTO. 64 core support is 1 year only this radiator basically drops in. Flow-Kooler1775 water pump-6 inch shaft. I have installed Old Air products A/C system- the crank and water pump pulleys are 3 groove.

 

The frames on the 64-67 cars are about 1.5" narrower than those on the 68-72 cars. When these cars were closer to new, there were a lot of headers available for the early cars. Today, there isn't enough of a market so header manufacturers have dropped those products. The 68-72 headers will usually be sized for the wider chassis. SBO and BBO headers are different. I'm not a fan of shorty headers, as the minuscule performance benefit does not justify the cost in my opinion. I'd run either full length headers or W/Z manifolds if you don't want to deal with header hassles.

 

Ok thanks ill I’ll take a look at your threads!

 

Yeah not sure I want to deal with the hassle might just have to go with the manifolds.

 

Hooker headers should fit well. The 65 to 72 BB Olds A body headers with 1 3/4 inch tubes.

 

That's the headers I have in the 64, tight but no issues, especially do what Joe said about the engine mounts or you will have fitment issues. I also have a Power Master high torque mini-starter comes right for service if need be without loosing or removing the header.

 

Looks good. What brand are they?

 

Hooker headers

 

That $300 engine is a $300 core until you know it turns over by hand and has good compression.

 

The alternator and power steering bracket need modifications to fit. I was able to reuse them after some welding/cutting. New belts are needed too.

I reused the old Hedman headers that were on the 350 in the car previously

The small block starter would not work once hot. So went to Powermaster ministarter

I think headers are well worth the effort

 

If I was you, I'd probably go with the factory W/Z exhaust manifolds. If you want headers, here's a thread for tube headers that are suppose to fit. The article also mentions the old rumor about Cutlass Supreme/convertible fitment. Even though the article is about header fitment on a 1967 442 and "all 1967 442's were Cutlass Supremes." If anyone has tried these headers, please post your results.
https://www.hotrod.com/articles/1967-oldsmobile-cutlass-headers

 

The key is for the headers ( don't know about Doug's) is like Joe mentioned, use the 330 engine mounts and frame mounts or you will have fitment issues. However the W-Z after market exhaust manifolds makes the motor swap easier, and you can use a high torque GM 4 field starter.

 

Just checking on your progress on the good looking F85 ?
I have done a couple of these swaps. Big block headers for 65 to 72 Cutlass fit in real good, but as has been said Thornton manifolds should work great.. T400 would be a better choice, but have to move trans X-member back and may need to drill new holes in the frame. And a new drive shaft 4 inch shorter. A T350 would be a bolt in, depending on your style of driving, the trans may not hold up to a major abuse.
Pic's of your progress would be cool.
Gene

 

Go for it...paint the 425 gold like a 330 and upgrade the transmission. Don't label the CID and make some Mustang owners want to sell their pony when the lights go green��!

 

The 425 I was looking at got sold. Waited to long. I’m looking for another at the moment. Closest one I’ve found is on the opposite side of Iowa from where I’m located. It’s a 1966 425 that needs rebuilt. Will be taking the engine and transmission out here in the next month when I park the car for the winter. I will post pictures and the progress when I find another big block.

 

What part of Iowa are you in? I’m on the Illinois side of the quad cities. There are a couple of complete 455s for sale locally.

 

I am on the West boarder 5 miles north of Sioux City, IA.

 

I know of a 65 f85 that has American Racing headers very tight fit. That same car had hooker headers and headman before changing. All big block as he was using a 455 engine.

 

I’ve found a couple of 425’s they’re bout about 4 hrs away one is still in a 1966 Olds 88 and the other is being taken out of a truck that’s been rebuilt but has a tick he believes is piston slap. I also saw there is a 394 for sale about an hour from me. Are 394’s any good? Or should I take look at the 425 with the tick.

 

Others that know more about 394's will chime in but its not a bolt in like the 330-425 as the 394 is a previous generation of engine. A 394 would also limit transmission options without an adapter. Probably much cleaner and simpler to stay with the generation of engine already in the car.

 

Ok that makes sense. Yeah I’d rather have a drop in then having to do any fabricating.

 

A 394 won't be a drop in. You want to stay with the 425 as your best option. You want a 425 with the 39 degree lifter bank angle. Be patient, one will turn up.

 

I agree with this.

 

I wouldn't pass over a good 45 degree motor. Mark Remmel can provide 45 deg cams for nearly the same price as a 39 deg cam. I'd be more worried about finding a block with 0.842" lifters rather than one with the harder-to-find 0.921" lifters.

 

Joe P, good point on the .842" lifters. Thanks Could you post the casting numbers for the OP of the 425 with .842 lifters and 39 degree lifter bank angle ?

 

What’s wrong with the .842 lifters vs the .921?

 

Nothing wrong with them, most 425's you find will have them but then you must determine your cam bank angle to see if its a 39 or 45 degree. All .921 lifter 425's have a 39 deg angle, 65 and 66 425's have the 45 deg if .842 lifters while most 67 425's have the 39 angle with .842 lifters.

 

0.842 lifters are common (also used on 1968-up Olds motors). 0.921 lifters can be difficult to find and expensive when you do.

 

I picked up a 65 425 with a th400. Motor was rebuilt 1999. Has Edelbrock intake carb and double rolling timing chain, comp cams roller rocker tips, melling oil pump, and Howard’s cam. Previous owner said he thought it was bored .030 over. I will be tearing it down going through the motor and possibly swapping in a more aggressive cam. I’ll let you know the progress throughout the winter. It came with flow tech headers for 65+ cutlass but I think I’ll look for manifolds over the winter.

 

Nice score.

 

Have it pulled apart now. Crank has a good sized mark on it and some of the cylinder walls are scored. Will have the crank turned. Gonna try to have the walls honed instead of boring it for now.

 

Don’t mix up the connecting rod caps.
Check at the crank shop, maybe they can just polish it.
none of the rods have spun, are they are all good?
does it have the big lifters? If so it’s a 39* cam. Just have to find the lifters.

 

It’s a 65 A block 425. That’s what I’m hoping is it can just be polished to get that grove lip off.

 

Hopefully the camshaft and lifters (in correct order) are good, it should be a 45° camshaft, not the later 1967 and after 39° camshaft.