Which is better for high performance / durability / parts? 263 or 320?

[raycow]

So... I've found three local junk yard Buicks with Str8s. Which years/models would have the 320, and how do I tell the difference most easily?

1936-39: Limited Series 90, Roadmaster Series 80 and Century Series 60
1940: Limited Series 80 & 90, Roadmaster Series 70 and Century Series 60
1941-42: Limited Series 90, Roadmaster Series 70 and Century Series 60
1946-52: Roadmaster Series 70 only

If the series name is not visible on the outside of the body, look for the Fisher Body ID plate on the firewall. It will have a Style Number of the form XX-XXXX. The first two digits are the year, and the third digit should be 4 if the car is a Buick. The fourth digit will be 9 for series 90, 8 for series 80, etc.

Ray

[alleycat]

This subject has been kicked around quite a bit here on team buick as to which is the better engine as well as all the "problems" that each engine has in reguards to performance building. You need to read almost everything here as there are some really good solutions to some difficult problems these engines have, put forth by the guys that post here. The fly in the ointment is that you will have to build everything yourself or have somebody build it for you since there is only a stock parts aftermarket for the str8 and NO performance aftermarket at all.
So, that being said, which is the "better" engine. It depends on what you are looking for. Some history: The 248 was based on a earlyer engine, the 233 of 1934-5, and went into cars in 36. The 233 and 248 are very much the same engine. The big engine of that time was the 344. It is almost totaly different from the 248 or the 320. The 320 has practicly nothing in common with the 344. So where did the 320 come from? It is a 17% bigger 248. There is not a particle of difference between the 2 engines other than size, and they virtualy did'nt change from start to finish. There are some issues that occure by just making a engine bigger, but since the 320 only put out barely 130 hp, no problem. But, at more serious power levels...You are dealing with a engine from 1935.
The 263 is a completely different fish. The only thing it has in common with the other 2 engines is 8 cylinders in a row. From the get-go the 263 was intended to be a totaly moderen preformance oriented engine. It was being tested in 38-9 and was intended to be in the new for 1940, Super. The top brass at GM did'nt like what it represented and the entire program was cancelled. It finally came out in 1950. The 263 actually stayed moderen up through the late 50s untill the short stroke/big bore V8's took over. It has nearly every performance feature in it you could need. It's main disadvantage? Displacement. The very best you'll get out of it is about 302 at a .240 overbore. And, you'd better have a good block to do it! 1950 only and no or little core shift. May be kinda tough to find a good candidate. Alleycat

[Untame]

This subject has been kicked around quite a bit here on team buick as to which is the better engine as well as all the "problems" that each engine has in reguards to performance building. You need to read almost everything here as there are some really good solutions to some difficult problems these engines have, put forth by the guys that post here. The fly in the ointment is that you will have to build everything yourself or have somebody build it for you since there is only a stock parts aftermarket for the str8 and NO performance aftermarket at all.
So, that being said, which is the "better" engine. It depends on what you are looking for. Some history: The 248 was based on a earlyer engine, the 233 of 1934-5, and went into cars in 36. The 233 and 248 are very much the same engine. The big engine of that time was the 344. It is almost totaly different from the 248 or the 320. The 320 has practicly nothing in common with the 344. So where did the 320 come from? It is a 17% bigger 248. There is not a particle of difference between the 2 engines other than size, and they virtualy did'nt change from start to finish. There are some issues that occure by just making a engine bigger, but since the 320 only put out barely 130 hp, no problem. But, at more serious power levels...You are dealing with a engine from 1935.
The 263 is a completely different fish. The only thing it has in common with the other 2 engines is 8 cylinders in a row. From the get-go the 263 was intended to be a totaly moderen preformance oriented engine. It was being tested in 38-9 and was intended to be in the new for 1940, Super. The top brass at GM did'nt like what it represented and the entire program was cancelled. It finally came out in 1950. The 263 actually stayed moderen up through the late 50s untill the short stroke/big bore V8's took over. It has nearly every performance feature in it you could need. It's main disadvantage? Displacement. The very best you'll get out of it is about 302 at a .240 overbore. And, you'd better have a good block to do it! 1950 only and no or little core shift. May be kinda tough to find a good candidate. Alleycat

Thanks! That's what I was getting at. I know more cubes are better in general, but if the 263 block and rotating assembly can handle higher compression and more revs, then I'd trade the bigger engine (and heavier) and play the hp/displacement ratio.

The other consideration is that if we develop something we are going to want to make it available in the aftermarket, so would the 263 or the 320 provide a larger marketplace for a high performance head?

[Untame]

You can find most everything from Bob's Automobilia, but some aftermarket engine components are off-shore crap. Camshafts aren't available, but you have a performance regrind by American Custom Cam or Elgin.

The stock 320 crank and rods are good for 600+ HP, according to Gerry Duttweiler. You can reach these numbers by super/turbocharging. The first item to let go is usually the #2 main cap - avoid excessive low-rpm torque (roots charger) and excessive compression ratio. Pioneers like Chuck/Gary Hamann and Gerry Duttweiler have revved the stock crank/rod combo past 7000 rpm and survived, though 5500 rpm is considered the safe red line.

The stock "turbulator" popup pistons are no good. You must get custom pistons made for you. Folks have used Ross and JE among others. 3.875" is considered the maximum overbore on a good core.

Convert the oiling system to a full-filtered system. The cooling system should be modified as well, to enter the block at the middlemost freeze plug.

The Olds 455 balancer can be fitted on the Buick crank pretty easily, as can the LS Chevy balancer, I hear.

You can get copper head gaskets with or w/o integral O-rings from Gerry Duttweiler in Ventura CA, phone 805-639-0237. Say hello from Jyrki

Awesome. Great information. Thanks for the help!

[Jenz38]

I understand right??A Performance-head for a 263 ?????
hmm..that will be great
in dreams Jenz

[Untame]

I understand right??A Performance-head for a 263 ?????
hmm..that will be great
in dreams Jenz

Actually, still leaning more toward the 320. Not sure which way we'll go. Which years/models did the 263 have modern bearings?

[Jenz38]

They are only build from 50-53 and have all modern bearings.
Jenz

[Jenz38]

Ohh..I completly forget, the Models,in the Super (Model 50) 50-52 and in the Special(Model 40)
50-53.

Jenz

[pmuller9]

The 320 is easy to identify because it measures over 34” along the top of the cylinder head
The 263 measures just under 32”

Obviously the 320 gives a displacement advantage over the 263 but in many cases (like ours) it is too long to stuff into the engine compartment of most vehicles.

The main crank journals of the 320 get progressively larger by 1/16” from front to back as do all other Buick straight 8s with the exception of the 263.

Line boring never seems to be needed but the 263 is the only block that can be if major block modifications were done like cross bolted mains or a girdle.

The 263 has a small bore diameter.
Notice how the beam side of the big end is a smaller width than the cap in order to pass the rod through the cylinder during installation.
This presents a challenge when considering an aftermarket rod.


263%20Rod.jpg

With the small bore diameter, any area designed for quench in the combustion chamber creates too much valve shrouding, so the suggestion would be to do an open chamber with just enough volume to allow 10:1 compression ratio using a spherical dish piston.
The aluminum 263 chamber shown below gives 10:1 compression with a flat top piston.

If you are doing a Hemi or multivalve crossflow head then you still need to find a balance between head volume and piston dish volume while keeping the combustion chamber shallow to reduce shrouding.


AlumChamber.jpg

Paul

[Untame]

Thanks for all the info, guys!

We're going with the 263. Now to find one...

I stopped by the salvage yard where I saw 3-4 Buick Str8s a year ago only to find out, "I crushed them."

Me: "What?"

Him: "Nobody wanted to give me what I wanted for them, and I got tired of arguing. The crusher doesn't argue with me."

Way to go, loser.

I see the one in the classifieds here, but it is about 11 hours from me (I'm in Western, WI).

Hopefully our shop will get started on this project in the next couple weeks if we can find a core.