Olds delta 88 custom L31 questions HELP !

[Pedal]

Hi guys !

Im from the Netherlands (Europa) and own a 1971 Oldsmobile delta 88 custom HTC with the L31 (455) package. The car is fully original ! (100,000 miles) and i have it from its first woner in the us.

I have the tags and broadcast sheet etc! , but cant find ANY info anywhere
on this car ! ( who many build , etc etc.) DOES ANYONE HERE or do you have
any info ??? iff so i would be VERY greathfull. If needed i can provide all tag's data etc.

Over here not much is known on Olds cars...

Here is a pick:

[Oldsfan]

There were 14,067 Delta 88 Custom Holiday Coupes built in '71. The L31 was the optional 225hp 4-bbl 455. Dual exhaust was optional and raised hp to 250. The L30 185hp 2-bbl 455 was standard.

If you want to know anything else, you'll have to be more specific.

Paul

[Pedal]

Originally Posted by Oldsfan

There were 14,067 Delta 88 Custom Holiday Coupes built in '71. The L31 was the optional 225hp 4-bbl 455. Dual exhaust was optional and raised hp to 250. The L30 185hp 2-bbl 455 was standard.

If you want to know anything else, you'll have to be more specific.

Paul

Hi Paul thanks for your reaction sofar.

My buildsheet / engine code UO (matching) tells me the engine should have 365 Sae HP ! ? so i cant tell,dont quit understand how you got to the 225-250 HP ?., the carb is a 4 barrel rochester no:7041251 RC 3630

Dont know what you need on info too be more specific ( iff possible) on buildnumbers and data but here is some more info on the car,

My vincode = 364571E1242xxx, and the the L31 option is on all the emblems
on the car ( rear emblem, in the stripekit on the hood,on both front fenders) etc. And on the original stripes at the rear its says: 455 rocket. Also the
trunklid has a couple of rows of louvres in it ( dont know the meaning of them there..)
The trans = a 400 turbo Hydro matic. The car color is original.

Is this helpfull to provide more details ?

Some olds guys here say there are only a handfull build of this type / model.?
but the cant realy back it up...



Sorry for my bad english....

[Kennybill]

They lowered the compression ratio for 1971, probably the 225/250 HP was under-rated a bit, this was when they were changing over to unleaded fuel which this car can run on. Nicer driving car then the 1970 and before cars. I have 2, 71's full-size, a convertible and a 98.

[Pedal]

Originally Posted by Kennybill

They lowered the compression ratio for 1971, probably the 225/250 HP was under-rated a bit, this was when they were changing over to unleaded fuel which this car can run on. Nicer driving car then the 1970 and before cars. I have 2, 71's full-size, a convertible and a 98.

Hy Ken,

Im no real expert , but i believe that what you are saying is for the later 1972 year engines. Mine still has ( factory original) high compression.

As with al muscle motors/cars the indeed changed the Sae rules 71/72 and as off 1972 most / all high perf. engines were killed of by the enviroment regulations etc, just by lowering compressions and ad all sorts of env.shit.

But as said , ( and i cheked on the motor) this engine of mine is an original
HP / high compression motor. ( thank god.... )

But i still hope i can find out more about this type of car......., and how many in this configuration were build, especialy because its one of the last treu "muscle" oldscar

[Oldsguy]

Hi, what a nice car! I answered your pm before i went to the forum listings and saw this thread so I didn't address the horsepower issue. I think that '72 was the first year for the "weak" low compression engine but what difference does it make anyway? I am sure you are totally elated with your car and love the way it drives?! I agree with Kenny, the '71 and later models ride much better. I had a '72 Delta four door sedan for a family car back in the mid eighties and it was a dream to drive, my wife loved it! It was yellow and the kids called it the "bannana boat".

[Pedal]

Thanks Oldsguy !.( also for the PM !).. hope you find out more..

As you said , i agree fully !. This car looks like a too heavy slow motion car...
BUT !!!! as a Musclecar fan ( and have more cars) i can say...

THIS THING RUNS LIKE CRAZY !!!.. Very fast enad steers fantasticly for
a this big a car !. And because of its good originaly maintained condition
it's like going back too the seventies every day i drive it !. WOW. i love
to drive it. No rumbles, engine runs like a swiss clock , brakes are suberb!
etc.

So yeb, your wright... fantastic cars.... THANKS

[69deltaconvert]

You can still make a fast motor with low compresion my 69 delta 88 with a 455 has an 8.5 to 1, but the whole motor was built as a low compresion pump gas rocker. Running 15.2 1/4 mile on 6 in. wide white walls with 89 octane pump gas. I like it, I even ran into a little bit of the the old leaded atitive a while back that motor came alive. And NICE car I want it, but I'm sure its cheeper to make a fake ( but the spirit is never there with a fake ).

[Oldsfan]

Pedal,

I've been meaning to address some things here and kept getting involved in other stuff. Now that I have some spare time here at home I can devote some time to this.

Let's start with horsepower. '71 was a transitional year for horsepower ratings. Oldsmobile quoted horsepower in Gross (which was the only figure quoted for 1970 and years prior) and S.A.E. Net (which they start using exclusively in '72 and later).

Gross rating is the engine on a dyno. No accessories, no exhaust, no nothing.

S.A.E. Net is the engine as installed in the car. Air cleaner, exhaust and engine accessories.

Oldsmobile rated the L31 455 at 320 Gross and 225 S.A.E. Net (250 with dual exhaust). That is out the dealer showroom album. I don't know where your 365 figure is coming from. The highest performance motors Olds had in '71 were the Toronado 455 and the W30 455, both rated at 350 Gross.

Now, those L31 emblems. It is hard to see them in the photos, but I do not think they are stock. L31 was just an engine option. It was not a package that included stripes and emblems. At least not that I am aware of. It was hard for me see the black stripes on the dark colored car on my computer at work. I see them now that I'm at home. I do not believe these are stock either. I've been told never to say never, but I have not seen another 88 with a blacked out hood and stripes such as these. There is nothing in my dealer materials about a stripe kit such as this. An 88 was an older persons car and do not believe Olds would have offered such a package. The only emblems on the car should be:

trunk - Oldsmobile script with Delta Custom plate underneath it.
fenders - Delta 88 script between the wheel and the door
roof - some sort of emblem on the sail panels - maybe a rocket
grille - Oldsmobile script on driver's side grille
front end - rocket emblem on nose piece

The louvers in the trunk lid are for the flow through ventilation, allowing air to enter the car at the grille at the base of the windshield, circulate through the interior into the trunk and be drawn out throught those louvers. They are a '71 only thing. They were eliminated for '72, I think due to water leaks, and were replaced by valves in each door jamb instead.

Paul

[Pedal]

Hi Paul !

First! , thanks for taking the effort to answer...!

Well im a bit stuned...., not for the figures of HP , because in that area there is many discussion about those things , no matter what car . But! al my paper work just keep on saying 365 HP (sae?/gross i dont know for sure) books, Other Olds fans and folks, olds engines websites, etc etc for the 70/71 L31 engine... , The compression ratio is above 1:10.3 , as i cheked that and has dual exhuasts ( i believe without it was 350 ..). ( motor is still 100% original and untouched!.) but as said . lets leave that for know, its not THAT important , its fast , that i do know ( and i am a dragracer so i know what fast is......... For sure ! its not an oldspeople car...it handles very good aswell! ( very thick stabilizers,anti roll bars etc(i believe original.)

I ask info here! so thats why i ask on this forum... so DONT think my comments are against you or something, NO THE are not !, just doubts and free discussion too learn more about this "strange" ? car ....

I cant remember where or when... BUT someone ( internet) told me once this car is one of about aprox 36 build sporty Olds ( in this set up) , and little is known about it , i didnt give it much thought back than , but i always asked myself , well , what about that , how can i check etc... and over here almost nobody knows anything about types of cars that are different than the standard cars...

BUT: , i will make fotos of all the emblems (the olds L31 ones ), but the realy seem VERY original!!. ( one on each front/side fender and 1 on the trunk, )
Also it says L31 on the hood in the small stripe around the black out part of it ( on the sides in red letters. ( i have a pick from that, and will also uploud later..) & why should someone fake that and SCREAM L31 everywere with emblems etc, if the motor is only 225 hp etc ?
BUT ? maybe someone did...? and had al decalls and stripes etc specialy made etc, you never know. Although i cant believe that...

The rear decal / stripe says 455 rocket on the sides ( the rocket word in gold/yellow ish..).and seems very original and like it has been always on the car.

IM NOT sure the blackout hood is the original way , but the stripe around it, the decalls and all other details seem original.
I have full buildsheet etc with the car ( and al original cowl and trunklid stickers are still in place.) so maybe we can find something there later on ?but i cant decipher all those codes, because a lack on input... .

Offcourse i will check you emble,/spec list too ( dont have the car here)., and tell you what i find there too... So ill get back too you asap..But the al seem to match , exept for the additional oldsmobile L31 decalls etc.
Another forum member here is checking out the car aswell i believe.

THANKS for know... !!., ill give more info asap ( ps dont misunderstand my bad english... , im dutch so difficult to realy communicate in a good way in mails...)

[Oldsfan]

Pedal,

If you've seen websites quoting 365hp, I would like to know what they are. I would like to see what you are seeing. That might lead to a better understanding.

Factory compression was 8.5:1 across the board in '71, even in the W30 high performance engine. Engines build up carbon over the years, increasing compression. Maybe that is why yours is testing at 10:1.

It is very possible that the package your car has was installed by a dealer, or a regional or local dealer marketing group. In that case, without documentation, you really don't have anything to go on.

It is also possible that someone went to alot of trouble and expense to have decals and emblems made up because they wanted the car to be different, or because that is what they liked. The graphics are not hard to do. Most sign painters or stripe places can do that stuff. The emblems are a different story. They would almost have at be cast of something - either plastic or metal. A mold would have to be created. That's a lot of expense and work to make 3 emblems to put on one car. Now, if there's another GM car out there that for some reason used emblems that said L31, problem solved.

Do you have the ability to scan the buildsheet you have?

Paul

[Pedal]

Originally Posted by Oldsfan

Pedal,

If you've seen websites quoting 365hp, I would like to know what they are. I would like to see what you are seeing. That might lead to a better understanding.

Factory compression was 8.5:1 across the board in '71, even in the W30 high performance engine. Engines build up carbon over the years, increasing compression. Maybe that is why yours is testing at 10:1.

It is very possible that the package your car has was installed by a dealer, or a regional or local dealer marketing group. In that case, without documentation, you really don't have anything to go on.

It is also possible that someone went to alot of trouble and expense to have decals and emblems made up because they wanted the car to be different, or because that is what they liked. The graphics are not hard to do. Most sign painters or stripe places can do that stuff. The emblems are a different story. They would almost have at be cast of something - either plastic or metal. A mold would have to be created. That's a lot of expense and work to make 3 emblems to put on one car. Now, if there's another GM car out there that for some reason used emblems that said L31, problem solved.

Do you have the ability to scan the buildsheet you have?

Paul

I will get al neccesary stuff and get back here in a couple of days ( im off for work for a view days..), The webs and book data im 100% sure i can find it.
I believe there was also something on a olds ROCKET forum somewhere.
Were the L31 70/71 was a high performance 455 in that year.
BUT maybe im wrong , but dont think so.

The emblems are so very fitting the oldsmobile logo's above that i dont think
there fake...

Maybe its ? as you say a special dealer type car ? does anybody now of these dealer car(s) ? was there a "yenko"type of olds dealer anywhere ?

BUT as said il get what is possible to figure out this car !

THANKS again so far !

[Pedal]

Here are some picks of the decals etc.!









Any help in Identifying the car type etc ?

ENGINE CODE: UO / 1143761
VINCODE: 364571E1242666
L31 option package.

More details ( buildsheet info) will follow.

HERE ARE THE WEBLINK FOR MY MOTOR:
http://www.442.com/oldsfaq/ofbbb.htm

Its says L31 :

Engine : 390hp 370hp 365hp 365hp 320hp
HP@RPM : 390@5000 370@5200 365@5000 365@4600 320@4200
Torque@RPM : 500@3200 500@3600 500@3200 510@3000 500@2400
Comp. ratio : 10.25-1 10.50-1 10.50-1 10.25-1 10.25-1
Carb : 4bbl 4bbl 4bbl 4bbl 4bbl
Exhaust : dual dual dual single dual
Cars : W33 W-30 W32 L31 L33

So compresion checks 1:10.25 and HP 365 !

[Oldsfan]

I am sorry, but I am still standing by my original opinion that someone added decals and badges to your car - nice car that it is. That "Rocket 455 L31" thing on the trunk lid should say "Delta Custom" I think someone either ground the lettering off of it, chromed it, and engraved it - or just went out and got chromed bars close to the same size and did the engraving on them. Same for the fender emblems - there shouldn't even be anything under the "Delta 88" on the fenders, but those bars look to be the same size as on the trunk, so somebody just made three of them up.

Now, as for your engine figures. I see now what you are looking at, and it is all for 1970 models. The W33 was not offered after 1970. NOTHING in '71 had a 10.25 or 10.50 compression ratio. The maximum compression in '71 was 8.5, hence the lowered horsepower ratings. Yes, the L31 had 365hp and 10.25 compression in 1970. But for '71 it was only 320 and 8.5.

The figures presented on that web page are for 1970, though it doesn't specifically state that.

Paul

[Pedal]

Well paul , incase of the decalls / tags i cant speak against you , because
i dont no eather if or what not original or special etc.
Although the rearside decall (455 rocket) is 100% correct , car has a 455 rocketmotor ( as also stated on my original air filter housing !, and other body items ) So im not realy confinced quit yet that its not a special sort of car etc.

But i keep thinking your wrong at the 71 engine specs. The lowered compression was done as from late 71/earlie 72 , MOST people tell me. Also the weblink i give is only one of many wich state its a 365hp car...
Also as i said earlier , i cheked my compression and cheked at 1:10+ aprox too so....
BUT HE.. i wasnt intrested so much in the cars HP as i still ! am in the origin.
I do also still believe , maybe its a dealer special, etc etc. because its al too proffesional done to be a privat job. The builtsheet i have states some things
too, ill check in too that again...

I thank you sofar ! , for your effort and opion!

[Oldsguy]

I do not know, wish I did. I lean toward the idea of a dealer package of some sort which may mean that car is one of a very few depending on how big the dealer is and how many of the L31 Deltas they sold. It is a very nice car though and regardless of it's origin you should keep it this way.

[Pedal]

Originally Posted by Oldsguy

I do not know, wish I did. I lean toward the idea of a dealer package of some sort which may mean that car is one of a very few depending on how big the dealer is and how many of the L31 Deltas they sold. It is a very nice car though and regardless of it's origin you should keep it this way.

Thanks for your findings, i agree, also becuase i think MAYBE the engine also has more HP than ( iff oldsguy is correct ?) its year , it also could be that
that particulair dealer also prepped the engine a little ( higher compresion etc)
Also strange is that the car has dual exhaust instead of single ( L31 had single). But the headers on the car seem very original , ao ar al the gaskets.
The engine is matching , but i didnt check out the heads etc. wil do so.

Yeb im very happy with the car and thats the most important , although.... my curiosity keeps me searching for answers... as you might understand.
especialy IFF its a rear ride... , iff not.. and some privat owner did it, no
wurrys , im still happy with it !

But some stories do say its 1 of about 30 build / deliverd in that year , by who
or what i , as you , do not know.. sadly.

Thanks guys !, iff there is ANY news ..no matter by who... lets keep eachother posted... please...

[Redog]

Damn that's a nice looking car!

How are the gas prices over there? Do you drive the car much?

[Pedal]

Originally Posted by Redog

Damn that's a nice looking car!

How are the gas prices over there? Do you drive the car much?

Thanks for the compliment !...

Gasprices sinds YEARS.. crazy over here... , i know in the US prices went up
the last time , but we pay more than double your prices ( everywhere in Europa BTW..), so your still very spoiled over there.... In fact iff you see things clearly we support your low gas prices and pay for the enviromental
costs too .....

But it doesnt matter , money must move, and yeb i / we still drive a lot , crazy enough you see more! muscle cars and old v8's on the street here
than when i visit the US ! , For daily driving diesel is populair here too and
so is LPG ( a kind of liqued gas, like were you cook on). Although most
cars run on petrol still.

Next too gas prices , we pay an additional tax for the road each year, ( not for oldtimers older than 25 years btw...) its about 1200 dollars p.year for a midzise car.....

So enjoy !!!! your ENORMESLY LOW prices... the will go up and up and up
there too i garantuee it....

BUT ! that wont get us down.. muscles and big v8's for ever !

[Oldsmaniac]

The car is beautiful!...I have been a member of the Oldsmobile Club of America for more than 30 years and I can tell you that the car is not factory and not dealer installed. Someone did a very professional job restoring and customizing your Delta. The black stripe and hood insert is similar to the 69 Dodge Superbee. It is a very nice look for your Olds and very professional. Great care was taken to make the paint and emblems look factory. It is obvious that the car has been repainted and I would guess the engine has been rebuilt with performance in mind. If that is the case you will have higher horsepower than factory. If the car was some rare edition surely others would have heard about them and factory literature would be available. GM and dealers didnt tool up to make only 30 cars....it is not financially feasable. By 1971 Olds was out of racing and performance was almost dead. I own many Oldsmobiles some pretty rare. I know a lot about the rarer cars from Oldsmobile like the 66 W-30, Hurst Olds, Rallye 350 and the like.....sorry but the L-31 edition that someone put together was his own creation. Good Luck with your one of a kind and beautiful ride!

[Specman]

PEdal, I agree with Oldsmaniac. I've been an olds watcher since 55. THis car is someone's custom wish car, perhaps even a dealer aftermarket custom who missed the old vintage big car sleeper "hotrods" like the Starfires and wanted them back instead of the 442's. I would have bought it, thats for sure. Nicely done. How bout posting some full body shots?

[Pedal]

In answer too Oldsfan & Specman. :

Thanks for the words guys !... And although im not a stubern guy.... , i still keep on searching for more info on this car. Didnt find the time yet too show my buildsheet and fendertags etc, but that, and offcourse ( specman) some better pics of the car etc.

In answer too some remarks:

Ths muscle car era was VERY alive in 1971 , oke maybe not hugely by olds , but see the Hemicuda's , challengers , Camaros etc. Also around 70/71
there were MANY dealers / shops who sold there own special cars..
also in SMALL amounts... Take Mr.Norm ( mopar ) who up untill 73 made
special cars ( demons and darts mostly) , Yenko ( also small numbers) ,
etc etc. SO ! its 100% not unthinkable that maybe there was a olds dealer
who did this too! ( if it was a succes i dont know). But i have all the first owner papers & buildsheet and maybe via that way i can find out more too.
I remember something about a handling package on the sheet , but not sure.


Engine / gearbox/ drivetrain etc etc ALL is matching numbers, and i dont think
touched or tuned sinds its origin ( 100000 original mile car...). And although some repaint work was done here and there, mostly it still has it original paint
and all the factory decalls (warning stuff etc) is still in place. The car doesnt
even have 1 serious rustsport or bubble !...


BUT ! maybe its wishfull thinking, i dont know... But its in my opinion too much work done for a private guy ( easpecialy with this model...its not a special 'stang etc..) Although the car handles fantasticly and brakes superb.
I drive and have many other muscles (mopar mostly: cudas, RR,s, etc), i must say that this car in power and steering is absolutly fast !, and handles
suberp! for sucha " hughe" car. I kill many camaro's ( and a mopar or two.... etcwith it !.

Although the car is going to be for sale one of these days, i still would like
too find out the story behind this "one of a kind" Olds...

Ill keep searching , and some more data & pics will follow here !

THANKS !: