who knows their Pontiac engines?

Ok I was poking around under the hood of the Olds today to try and figure out once and for all what engine was shoved in there.

Sadly I cannot get a good view of the side of the block to tell the size for sure. So far the markings I have found are "XD" on the front of the passenger side cylinder bank. The heads are marked H107 and the intake manifold is 10000516.

The number from the intake would indicate its from a 78-81 301, in 78 XD on the block indicated a 301. However the H107 would indicate they are from a '77, which the XD in that year was the 400.

The engine block, heads and valve covers are all painted and well worn blue. The intake manifold is not painted so I'm thinking (and hoping) that someone stock the 301 intake on the 400 for some reason.

Any other easy ways to tell the two engines apart or am I going to have to wait until I can pull it and look at the side?

Ok, here's your info:

A 301 manifold will be single plane with siamesed runners, you will only have four runners for all eight cylinders, they will have two cylinder numbers cast onto each runner.

A dead giveaway for the 301 engine is three bolts on the centre exhaust port instead of two like every other pontiac engine.

The 301 heads will have "01" cast on the centre exhaust ports.

The 301 is a short-deck motor and the manifold will not fit a 400, the 400 is wider.

The casting number on your intake is a casting number for a 301 or 265 2-barrel intake.

The block code is indeed for a 301, 78XD tells me it's a 301 2-barrel from a B-body or A-body car.

Go here: www.301garage.com

I'm one of the mods on the forum and I also run a parts business specialising in 301 and 265 engines.

My racecar runs a Turbo 301, tell me what you need to know.

Shawn

Hmmm I was really hoping that the engine was not a 301 as that means basically a throw away for me.

I just went out and yeah it has "01" on the center exhaust (had to remove a clip to see it).

So yep gonna be digging up a new engine for sure now oh well at least I got that figured out for sure.

Thanks for the info Shawn. Oh the engine mounts for this should be the same as a 400 right? More then likely will end up with a Chevy but if I can dig up a 400 I might go with that.

Depending on what Olds it is, you can put absolutely any GM under that hood you want with a simple combo of engine mounts.

What is the car again?

curtis73 wrote: What is the car again?

Its a 1980 Olds Cutlass. I'm torn between doing an older carbed engine like the 400 or doing a more modern injected engine. I'm still kinda liking the idea of building it as a pro touring car.

Why not keep the 301? Trans_Maro sounds like he can hook you up & it may not be any more expensive than sourcing a "popular" lump like the 400.

two words: caddy 500

What's wrong with that motor?

Is it running or not?

A 301 will provide more than enough power for that chassis unless you want to get really silly.

If you do swap it out, stick with a B.O.P. family engine, a Chevy will require some extra work to install.

Chevrolet puts the battery and starter on the wrong side of the engine bay, you'll have to extend the wiring harness.

The motor mounts will need to be placed in different holes in the frame because the Chev motor is narrower. Believe me, this is more of a pain than it sounds, the LCA's will have to come out.

There are some limits to the 301, the crank won't live long if it see sustained RPM over 5000. It's externally balanced with only two counterweights on the crank. The heads don't flow great but they do ok. A good cam, headers and a 4-barrel will wake that sucker right up.

Any Pontiac exhaust manifold will bolt up, you can take advantage of the great-flowing and stock-looking Ram Air exhaust manifolds, they're basicly cast-iron shorty headers. One of the local Poncho drag racers picked up a couple tenths when he ditched his headers and installed RA manifolds.

Remember, these are smog-choked 1970's / 1980's engines. A decent cam profile and a few simple tricks will fix most of their problems.

They have the same bore x stroke as a Ford 302, there's no reason they can't be made to perform ok for street use.

Because Pontiac put the 301 on a diet, it's actually lighter than a SBC. Less weight in the nose = better balanced car.

They won't post huge HP numbers because they can't rev high. The do make huge amounts of torque (remember HP is torque and RPM) all below 2000 rpm. Pontiac engines aren't like Chevy engines, you don't need to rev the snot out of them to get power.

Sounds like a good stoplight racer engine doesn't it?

Don't forget, your olds probably has lousy, economy car gearing in the diff. Switch to something a bit lower, say 3.42 or so and you'll like it.

So, headers, 4-barrel, good camshaft, shift kit in the trans and better gears in the rear end (you've probably got 3:08 or worse, probably worse) and you'll do fine.

Best part is, you already have an engine in the car that doesn't cost any extra. You can always take it out later if you don't like it.

Good luck.

Shawn

Well the engine is currently not running and everything is going to be yanked anyway during rebuild basically gutting the whole car. Though I don't know why its not running (came that way when I drug it home), and until I get my garage space back I won't know for sure. Need a radiator and a distributor for it at the minimum both are missing.

One of the eventual uses for the car will be to take it to some auto crosses for some fun when I head to Portland and the like.

I was looking to get somewhat silly with the car wanting between 300 and 400 hp. It was not planned as a daily driver, more of a weekend run about and something to have fun with. What is the potential of the 301 NA? I would be more interested in keeping it if it had been a 301 Turbo as more of an odd ball thing to have. As I remember they are different blocks though right?

Trans I have lined up is a Muncie 4spd and my uncle has a line on a Ford 9 inch rear that has been modified to fit the Cutty. Though I played with the idea of a 5 or 6 spd as well.