Hi All,
Just wondered if there is any way to distinguish between the two versions of 4bbl 455 that Olds put in the 1969 Delta 88? Looks like both were hi-compression, but one (I believe the W33) is rated at 390hp, whereas the other is at 360hp. I have a 4bbl '69 motor out of an 88, don't know which version, just wondered what the differences were between the two. Getting ready to drop this in my '70 convertible, and am curious to know which motor I have. Any help is appreciated, thanks

 

Probably mostly
cam
dual exhaust
timing and distributor

One might be UHC Ultra High Compression 10.5:1 vs HC at 10.25:1

Practically- not much difference

 

According to the engine specifications chart for 1969, a low-compression (9 to 1), regular-fuel 455 with 2-bbl carb putting out 310 hp was the standard engine in the Delta 88 Custom and Delta 88 Royale and was an option in the base Delta 88, for which the 350 was the base engine.

A high-compression (10.25 to 1), 4-bbl carb, 365 hp version was an option on all Delta 88 models. These cars came with single exhaust.

A 390 hp, high-compression, 4-bbl carb version was also available on all Delta 88s. Such cars came with dual exhaust, and the heavy-duty version of the Turbo Hydramatic 400 and heavy duty cooling system were required options.


According to the spec charts, the highest compression ratio in a 455 that year was 10.25 to 1, even in the most powerful 455 that year, the 400 hp version (W34) offered only on the Toronado. 10.5 to 1 was available in the 400 and 350.

 

Don't forget about the Hurst Olds 455 engine.

 

That's a separate issue, isn't it? I'm talking about engines available from the factory. Weren't the Hurst engines modified later? Also, the OP is interested in engines available in the Delta 88. Was the Hurst 455 ever made available in that car?

 

Contrary to the "official" story, the 68-69 H/O 455s were installed at the factory, since they had to drive the cars off the end of the assembly line. Toro W34 short block with D heads.

As for telling the D88 engines apart, the only real way to do it is to tear the motor down, checking the piston dish, valve size, and cam lobe profile.

 

Thanks for the clarification.


Also, if the engine was still in the original car, couldn't you just look at the top of the air cleaner or the fuel filler cap and see if it says "premium fuel only?"

There were really only two 445s, right? One low compression, one high, and the differences in hp available other than the compression difference was in choice of carburetor and single or dual exhaust?

 

Good question as there were two 4-bbl 455s available in the Deltas: the 365 hp L31 and the 390 hp L32. The L32 was essentially the same as the '70 W33, but the W33 was a '70 only designation.
The are only 2 external indications:
1. Dual exhaust manifolds for the L32. But of course the manifolds could be changed.
2. Distributor. The L31 has #1111934 and the L32 is #1111936. Less likely to be changed, but still possible.
Both had the same 10:25 pistons, same carbs, the only thing else internally was the cam and larger valves in the L32.

 

Kurt, check your W32/L32 typo.

 

Also, if the transmission is original to the car (the VIN derivative matches), then the L32 390hp car will have an OL transmission tag, while the regular L31 365hp car will have an OJ or OK transmission tag.

- Eric

 

Sounds like it is just the engine:

 

Good point. Missed that.

 

Thanks Dan. You mean both of them??? Corrected them both. I already corrected the W31 I had twice before I posted the first time.

 

Great information, thanks to everyone who posted on this.

Based on the info everyone provided, I think I have the L31 365hp version based on the fact that it has the 4bbl carb with single exhaust, which I'm very sure is original.

HOWEVER -- I have distributor #1111935 (not the 1111934 or 1111936), and have the original TH400 tranny, which is an OB code (not OJ or OK).. Still, this was definitely not a dual-exhaust car, so have to assume I have the L31??

 

Whoops, I forgot the OB transmission (which is funny, since I've had one in the shed for 20 years... ).
455 4bbl 10.25:1, no cruise control: OB
455 4bbl 10.25:1, with cruise control: OK
455 4bbl L-32: OL
455 4bbl Toro: OJ
455 4bbl Toro W34: OM

Distributor -935 is listed as 455 High Compression, except W34.
Distributor -934 is listed as 455 Low Compression
Distributor -936 is listed as 455 High Compression with W34.

- Eric

 

Good stuff, thanks Eric. Sounds like this confirms it, hi-comp L31 365hp it is..

 

"There were really only two 445s, right? One low compression, one high, and the differences in hp available other than the compression difference was in choice of carburetor and single or dual exhaust?"

Must be an echo in here.


"455 4bbl 10.25:1, no cruise control: OB
455 4bbl 10.25:1, with cruise control: OK
455 4bbl L-32: OL
455 4bbl Toro: OK
455 4bbl Toro W34: OM"
=====================
Damn Typos.
An OK RWD trans in a Toro would be quite a trick.
OJ was the std issue Toro trans code for years, with OM the W34 unit.

 

Maybe rattling around inside your head.


The "high" and "low" compression 455s were not 10.5 to 1 and 10.25 to 1, as your post said:

One might be UHC Ultra High Compression 10.5:1 vs HC at 10.25:1


They were 10.25 to 1 and 9 to 1.

 

Who put the darned K button right next to the J button???

Shouldn't type while eating my cereal in the morning - it's a good morning if I don't accidentally pour Ritz crackers in the bowl and then pour milk on them.

- Eric