I know this thread could be placed into the Engine category & yes, I did search this forum. What are the pro's & con's between 1965-1967 and 1968-1969 400ci engines used in the 442?

1965-1967 400ci engines are:
1. short stroke (3.975)
2. better performance
3. 350-hp / 440-torque

1968-1969 400ci engines are:
1. long stroke (4.25)
2. designed for emissions
3. 350-hp / 440-torque (325-hp with auto)

On paper, the engines seem to be equal. Be aware I'm excluding the L69 & W30 performance options. Please help me understand the differences between the two generations of 400ci 442 engines.

Thank you

 

The early 400E's are much better end of sentence. But if your building a stock restoration motor doesn't matter? But if you have a choice? I can clearly remember my 69 400 4-speed back in 70 would not hold a candle to the others, GTO's, 396 Chevelle etc. Mine was bone stock.

 

Agreed. I guess its the engineer in me wondering about differences between two generations 400ci engines. The greater question is why did Oldsmobile change the secret sauce? I've recall reading somewhere, the change was due emission requirements.

I've been told by numerous 442 owners ('68-'69) the 400ci redesign was not kind to them in racing (track / street).

 

It was emissions related, the long stroke did not work well on that bore size. That's why I believe the 425 is such a sleeper build same short stroke, steel crank but 25 more cubes to work with.

 

I have heard that they said it was for emissions by reducing cylinder quench but it was done as a cost cutting mode so they could use the same crank with the 455 & the 400.

 

Whenever I see these type of topics on a forum, I always say; “Uh oh, here comes the fisticuffs”. It is too easy to have a thread like this degenerate in to opinions . . . like: “Oh, yeah, my (whatever) can kick your (whatever)’s . . ..

Over the years, I’ve seen the topic of the long stroke 400 (LS) versus the short-stroke 400 (SS) be batted around like a tennis ball, with little facts to back whatever was being said.

Yes, the 400 LS was developed because Olds did not want to have two sets of cranks and rods in the inventory, but frankly the factory engineers did not anticipate problems with the motor – which I go into below. It was common practice to try to keep additional parts to minimum and to keep costs down wherever possible. Yes, the long stroke motor was better for emissions, but the added stroke was basically the only way to increase the displacement of the motor which was considered necessary to lug around those heavier and heavier 98s. (Plus a slower turning motor is quieter – something 98 owners wanted). Remember that 30 thousand units (the 400 LS) is small potatoes in a company that was selling over 500 thousand cars per year.

First, the issue of the performance of the LS 400 versus the SS 400 should be put to rest right now – they were equal – especially so in stock trim. Why do I say this? Not because I’m an old-timer (I am) but we have documents to prove it at Wild About Cars. In our tech Section and our Magazine Section, we have the actual road tests of the cars from Back in the Day (BITD) and you would be surprised. First, the auto trans cars were similar with the edge to the ’68 at 15.13 and 92 mph versus the ’67 at 15.8 @91, mostly due to the 3.42 rear in the ’68).

Here’s the Car Life test of the 1968 (3.42 rear): http://wildaboutcarsonline.com/members/AardvarkPublisherAttachments/9990392728558/1968-06_CL_Olds_442_1-4.pdf 3.42

Here’s the Car and Driver test of the 1967 (3.08 rear): http://wildaboutcarsonline.com/members/AardvarkPublisherAttachments/9990391522580/1966-12_CD_67_Olds_442_1-4.pdf


The W-30 cars were also pretty comparable as well, with the ’67 running about 14 flat in street trim. And the ’68, when equipped with headers and cheater slicks ran in low 13s. We know that these cars would all get into the mid-12’s with the proper setup.

Here’s an article on the ’67 stick W-30 (4.33s): http://wildaboutcarsonline.com/members/AardvarkPublisherAttachments/9990391431456/1967-10_HPC_1967_Olds_442_W-30_Test_1-5.pdf

And here is a strip test of the ’68 in pretty much stock trim (4.33s)
http://wildaboutcarsonline.com/members/AardvarkPublisherAttachments/9990392493645/1968-08_CC_Olds_Coupes_De_Grace_1-5.pdf

Now, as to how the LS 442 was perceived by the motoring press and the public at the time. Two magazines picked the 442 as one of its top cars for 1968.

Car Life made it a “Top Ten” pick:
http://wildaboutcarsonline.com/members/AardvarkPublisherAttachments/9990392729582/1968-09_CL_Ten_Best_of_1968_-_Olds_442_1-2A.pdf

And Cars Magazine Awarded the 1968 442 Top Performance Car of the Year:
http://wildaboutcarsonline.com/members/AardvarkPublisherAttachments/9990401391265/1968-03_HPC_442_Wins_1968_Performance_Car_of_the_Year_1-5.pdf

When we get into the vulnerability of the LS, that came about in retrospect, and only in race trim for the most part. We can go over the reasons why it developed a propensity to spin rod bearings, but as Tweed Vorhaus will tell you (he campaigned a ’67 W-30 in NHRA BITD), the short stroke would too. (He will also tell you that in ’68, he had his clock cleaned by the factory teams running the 68 W-30 – which ought to tell you something).

The ‘68s problem can be traced to a bunch of things, all of which could be cured, but what happened for the most part was that the long stroke was happier at lower rpm, but the factory made two critical mistakes: First, they added the 328 cam, which pushed the rpm capability higher and second, they equipped the car with 4.33s as standard equipment. Both led to over-revving the engine and resulted in a lot of warranty claims. Second, there is contention that the small bore resulted in excessive piston rock and stress on the rod bearing, though this has never been proven.

What really happened was that the W-31 appeared and race teams moved to this car as it was just more capable of winning its class, Stock Eliminator, and it was very hard to break. Second, the 400 LS was only a 2-year engine and the 455 just made 442s and W-30s much more formidable. As a result, the car was later maligned much more than necessary.

So, to answer the questions: Surely the SS 400 can be modified to deliver more consistent power and longevity, and it does not suffer the small bore and long stroke idiosyncrasy, but on the street the LS and SS were pretty even. BITD, however, the ’68-’69 was considered a very good supercar (they didn’t call them muscle cars back then).

I hope you enjoy reading these articles – we have hundreds more road tests and magazine articles on the site and we feature a “Back in the Day test each week.

 

You the man!!! Thank you so much for providing this level of information. You have provided me several days worth of reading

In your opinion which was the better engine, '65-'67 or '68-'69?

 

"Better" is an operative word. Better for the street? Both will run fine and make equal HP - with the LS making more torque - and BITD we used to say, "On the street, torque talks."

If I was doing a build from scratch or as a race motor - without one or the other in hand I would choose the SS, but if I had a 400 LS, there is plenty that can be done to make that engine live in race conditions.

Both are getting harder and harder to find parts for - in fact it is a better deal to build the 425 block or 455 block if you are going racing.