The 'other' 60's turbo car: Olds F85 Jetfire!

[miniman82]

Finally managed to get my hands on a pair of these Jetfire turbochargers, I've been looking forever. They seldom come up for sale, because owners didn't like the turbo 215 and the factory even swapped the system for a 4-barrel upon customer request! Because of that, they are like finding rocking horse sh!t to quote the British. I'm interested in these for 2 reasons:

1. The Olds Jetfire and Corvair 150hp Spyder were the first 2 cars on the market to use turbos
2. Garrett (called Airesearch in the early days) made these units, which makes them among the earliest of the T-series. I've been around Garrett turbos since the beginning, so it's interesting from a historical standpoint to me.

I plan to learn as much as possible on these pieces of auto history, maybe I'll even publish a short manual on them like I did for the TRW/Rajay units our cars use. Also, I find it interesting that Olds would put a T3 sized turbo on a 3.5L V8. This little thing would still be too small for a Corvair, what were they thinking? One for each bank would have been about ideal.

[bbodie52]

A lot of interesting facts here. In addition to the unique and creative design, engineering and marketing work being done by GM with the Corvair in the late-1950s and 1960s, I remembered as a teenager hearing about the turbocharged Oldsmobile and an aluminum engine from Buick. I knew they existed, and only, it seemed, for a short production period, but I never heard much else about their successes and failures with those projects. Your post brought about some interest and piqued my curiosity, so after a brief Google search, here is some more info I found on Wikipedia...

http://en.wikipedia.org/wiki/Buick_V8_engine

BUICK "SMALL BLOCK"

In 1961, Buick unveiled an entirely new small V8 engine with aluminum cylinder heads and cylinder block. Lightweight and powerful, the aluminum V8 also spawned a turbocharged version, (only in the 1962-63 Oldsmobile Cutlass version), the first ever offered in a passenger car. It became the basis of a highly successful cast iron V6 engine, the Fireball. The all-aluminum V8 engine was dropped after the 1963 model year, but was replaced with very similar cast-iron block/aluminum head for one year, and then all iron, engines.

GM experimented with aluminum engines starting in the early 1950s. Alcoa (Aluminum Company of America) was pushing all automakers to use more aluminum. An early development model was used in the 1951 Le Sabre concept car,[2] and the 1953 Buick Roadmaster concept car, and work on a production unit commenced in 1956. Originally intended for 180-cubic-inch (2.9 L) displacement, Buick was designated by GM as the engine design leader, and decided to begin with a larger, 215-cubic-inch (3.5 L) size, which was deemed ideal for the new "senior compact cars" introduced for the 1961 model year. This group of cars was commonly referred to as the "B-O-P" group — for Buick-Olds-Pontiac — or the Y-bodies.

Known variously as the Fireball and Skylark by Buick (and as Rockette, Cutlass, and Turbo-Rocket by Oldsmobile),[3] the 215 had a 4.24 in (108 mm) bore spacing, a bore of 3.5 in (89 mm), and a stroke of 2.8 in (71 mm), for an actual displacement of 215.5 cu in (3,531 cc). The engine was the lightest mass-production V8 in the world, with a dry weight of only 318 lb (144 kg). Measuring 28 in (71 cm) long, 26 in (66 cm) wide, and 27 in (69 cm) high (same as the small-block Chevy)[4] it was standard equipment in the 1961 Buick Special.

Oldsmobile and Pontiac also used the all-aluminum 215 on its mid-sized cars, the Oldsmobile F-85, Cutlass and Jetfire, and Pontiac Tempest and LeMans. Pontiac used the Buick version of the 215; Oldsmobile had its own. The Oldsmobile version of this engine, although sharing the same basic architecture, had cylinder heads and angled valve covers designed by Oldsmobile engineers to look like a traditional Olds V8, and was produced on a separate assembly line. Among the differences between the Oldsmobile from the Buick versions, it was somewhat heavier, at 350 lb (160 kg). The design differences were in the cylinder heads: Buick used a 5-bolt pattern around each cylinder where Oldsmobile went to a 6-bolt pattern. The 6th bolt was added to the intake manifold side of the head, one extra bolt for each cylinder, meant to alleviate a head-warping problem on high-compression versions. This meant that Oldsmobile heads would go on Buick blocks, but not vice versa. Changing the compression ratio on an Oldsmobile 215 required changing the heads, but on a Buick 215, only the pistons, which was less expensive and simpler. For that reason, the more common Buick version which looks like a traditional Buick vertical valve cover 'nailhead' V8 (but isn't) has today also emerged as more desirable to some. But the Olds wedge shaped/quench combustion chambers/pistons are more compatible to modern low octane/low lead gasolines than the Buick 'hemisperical' shaped combustion chambers and domed pistons. Later Rover versions of the aluminum block and subsequent Buick iron small blocks (300 with aluminum, then iron heads, 340 and 350 with iron heads) went to a 4-bolt-per-cylinder pattern.

At introduction, Buick's 215 was rated 150 hp (110 kW) at 4400 rpm. This was raised soon after introduction to 155 hp (116 kW) at 4600 rpm. 220 lb·ft (298 N·m) of torque was produced at 2400 rpm with a Rochester 2GC (DualJet) two-barrel carburetor and 8.8:1 compression ratio. A mid-year introduction was the Buick Special Skylark version, which had 10.00:1 compression and a four-barrel carburetor, raising output to 185 hp (138 kW) at 4800 rpm and 230 lb·ft (312 N·m) at 2800 rpm.

For 1962, the four-barrel engine increased the compression ratio to 10.25:1, raising it to 190 hp (140 kW) at 4800 rpm and 235 lb·ft (319 N·m) at 3000 rpm. The two-barrel engine was unchanged. For 1963, the four-barrel was bumped to 11:1 compression and an even 200 hp (150 kW) at 5000 rpm and 240 lb·ft (325 N·m) at 3200 rpm, a respectable 0.93 hp/cu in (56.6 hp/L).

Unfortunately, the great expense of the aluminum engine led to its cancellation after the 1963 model year. The engine had an abnormally high scrap ratio due to hidden block-casting porosity problems, which caused serious oil leaks. Another problem was clogged radiators from antifreeze mixtures incompatible with aluminum. It was said that one of the major problems was because they had to make extensive use of air gauging to check for casting leaks during the manufacturing process, and not being able to detect leaks on blocks that were as much as 95% complete. This raised the cost of complete engines to more than that of a comparable all cast-iron engine. Casting sealing technology was not advanced enough at that time to prevent the high scrap rates...

It sounds like GM executives permitted a great deal of experimentation in design, engineering and marketing in the mid-1950s and 1960s, probably starting with the Chevrolet sports car -- the Corvette -- and then with the rear-engine Corvair and the Buick/Oldsmobile small-block efforts using aluminum and turbocharging. An interesting era for such a large corporate entity like GM to be willing to take such unusual, unconventional and controversial approaches in the automotive industry.

An interesting period in automotive history, to be sure! The Corvette was obviously successful, as was the Corvair for ten years. The Oldsmobile and Buick efforts -- not so much. But still a step in the right direction for "pushing the envelope". And it gave us the Corvair, which makes us happy!

[Phil Dally]

One of my favorite cars I ever owned was a 64 Buick Skylark.

225 cube iron block odd fire V6 one barrel Rodchester with a PG.

Drove the wheels off it until I blew the head gasket late for work one day.

Should have fix it and kept it...oh well.

The 64 is distinctive by the tiny little tail lights.

In 65 is was a full width light bar.

[TheHillsOfSlandro]

I had a 1962 Olds F85 with the aluminum 215 V8. Not the turbo jetfire though. I sold it about 6 months ago.

[TheHillsOfSlandro]

f85II.jpg (58.05 KiB) Viewed 3403 times

[bbodie52]

Also, I find it interesting that Olds would put a T3 sized turbo on a 3.5L V8. This little thing would still be too small for a Corvair, what were they thinking? One for each bank would have been about ideal

So the turbo used by Olds 215 ci Olds engine was significantly SMALLER than the Corvair turbo used on the 145 ci, and later 164 ci engines? If Oldsmobile engineers had utilized a proportionally larger single turbo for their 215 ci engine, would the larger turbine and impeller have caused significant spin-up delays because of the added mass and weight? I suppose that doubling the turbos, as you suggested, with two of the smaller T3-sized turbos would have avoided turbo lag, but would also have doubled the cost and would have added complexity. In a world where the aluminum engine costs and production problems were already killing the aluminum engine, the use of two small turbos would probably have been unacceptable..

Turbochargers in production vehicles are still rare. I have a single turbo in my 1991 Toyota Supra, and Toyota later introduced twin turbos in the following generation Supra (although production was short lived). Where are the turbochargers now?

[miniman82]

So the turbo used by Olds in the 215 ci engine was significantly SMALLER than the Corvair turbo used on the 145 ci, and later 164 ci engines?

Much smaller; they aren't the same turbo by a long shot, but I'll explain what I know as of right now. Keep in mind: this is all my own opinion, and you have to see this from the perspective of someone who knows turbo tech looking back on what GM did.

In the 150hp Spyder engine, there was a drastically undersized compressor wheel but the turbine was about the correct size to give appropriate boost response. This means that while it was fun to drive, its performance was severely limited by its inefficient compressor. In the 180hp engine, the turbine was slightly too large and the compressor was again on the small side. This meant that its performance was somewhat lacking, because of the lag in boost onset caused by the large turbine.

It's possible that the reason for limited boost in the 150 and late boost in the 180 was because GM was all too aware of the limitations inherent in the cooling system of the aircooled powerplant, so they made sure that destruction of the engine was to be avoided at all costs- it was designed into the engine from the very beginning. Because neither engine was capable of more than about 10 psi even on a very hard run, I suspect that a large compressor would not have been seen as needed by the engineers. It could also be that they wanted to avoid undue transmission failures that might have been caused by loads of low RPM turbo torque, but that's purely speculation. Remember, these were folks that were pushing the envelope of what was possible, but they still had a company to look out for and so warranty claims were still a consideration.

Now let's look at the Jetfire.

Here's a 3.5L all aluminum V8 engine, cooled by water not air. It had more than enough cooling capacity to handle the turbocharger, so you would think they would go balls out on it. Not the case. On the contrary, they opted instead to use a very small turbo and also keep a very high static compression ratio. I can't say what motivated this decision, but it could be that they were directed to work with a base engine already in production. Since the turbo couldn't reliably add much power to an engine already at 10.25:1, 5 psi boost was the target, with any detonation being moderated by alcohol injection. Since only 5 psi was on tap, a large compressor wheel was not needed just like with the Corvair. The choice of such a small turbine could be explained by engineering wanting a flat torque curve, and instant reponse. Again, speculation. The main difference between the Corvair and F85 stuff is the F85 had a wastegate, and so a restrictive carb throat wasn't required to control boost pressure as it was with the Corvair. This may also have played into the turbine wheel size decision, since even a very small turbine could be controlled reliably via the wastegate. (without a wastegate, I suspect GM went with a slightly large turbine to help control the system).

If Oldsmobile engineers had utilized a proportionally larger single turbo for their 215 ci engine, would the larger turbine and impeller have caused significant spin-up delays because of the added mass and weight?

Possible. Though with 8 cylinders, spooling even a large turbo is easier than with only 4 or 6. It goes back to what they were trying to achieve, and we can't possibly know what they were thinking. Knowing what I know about OEM turbo engines today, they don't want a 'peaky' engine by any means. What they are after is as flat and broad a torque curve as possible, so it operates just like an N/A engine. That means you need nearly off-idle boost response, which could have been a contributing factor to turbine selection back then just as it is now.

I suppose that doubling the turbos, as you suggested, with two of the smaller T3-sized turbos would have avoided turbo lag, but would also have doubled the cost and would have added complexity.

Very true. Can you imagine a twin turbo 215 though? Would have been an absolute blast to drive. I believe that technology was holding them back, same as it was with the Corvair. That is the ultimate reason why the idea was abandoned, it didn't resurface again till the advent of multipoint injection in the early 80's when they had better control of the engine.

In a world where the aluminum engine costs and production problems were already killing the aluminum engine, the use of two small turbos would probably have been unacceptable.

Indeed, one turbo was eventually seen as unacceptable. lol

Turbochargers in production vehicles are still rare. I have a single turbo in my 1991 Toyota Supra, and Toyota later introduced twin turbos in the following generation Supra (although production was short lived). Where are the turbochargers now?

Actually, I believe turbos are again making a comeback because of rising fuel prices. Subaru, Mitsubishi, Ford, VW, Nissan, Dodge and Audi all have production turbocharged engines out there, though at a cost premium vs older technology. I personally have been waiting for this to happen for a long time, because large engines that suck down gas simply don't interest me. I'm not one of those greenie eco-nuts or anything like that, it's simply that we have had the technology to make better engines for a very long time but have chosen not to pursue that avenue. Why? The cost of fuel was low, so there was no incentive. So to a certain extent, I do believe that fuel should remain at around $3.50~$4.00 a gallon. There's simply no excuse for being so wasteful, especially when no one knows how much gasoline there is in the world for us all to use.

Back on topic though, technology was what kept them from making a truely viable turbocharged engine back in the 60's.

As for the turbos themselves, the Jetfire unit shares much in common with the TRW/Rajay unit from the Corvair. Both have radial compressors, neither of which involve backwards curved blades because it hadn't been invented yet. Both Corvair units employed full bladed compressors, while the earlier Jetfire unit had a split blade design (one set of fins lower than the other to improve flow). I found that strange since it was introduced first, only the E-flow Rajay wheel is like that. Both units have a positive-style carbon faced seal, but the Jetfire unit is encapsulated vs the rebuildable 4-piece design chosen by TRW. For bearings, the Jetfire unit has full floating bearings while the TRW has a pinned non-floating one. This architecture has been used by Garrett ever since the beginning then, because they still have a nearly identical support structure for the shaft to this day.

More later, my fingers are tired.

[flat6_musik]

On the contrary, they opted instead to use a very small turbo and also keep a very high static compression ratio. I can't say what motivated this decision, but it could be that they were directed to work with a base engine already in production.

Check out this article......maybe GM was WAYYYYY ahead of their time! BTW, did you know that the Olds turbo used (what they called) "Turbo Rocket Fluid" as their water/alcohol injection? LOL Google it. And apparently there was a light on the floor shift console that illuminated when the tank went empty. Guess with 10.5 to 1 compression, the situation could be devastating! I used to work at an Olds dealer in the 70's as a mechanic, and I had actually heard of the 215 turbo and asked a few of the old-timers there who told me those 215 turbos were blowing up left and right. One old guy said he took one on a road test, and ended up walking back to the shop holding 1/2 of a camshaft. (never know how much was imbellishment..lol)

http://www.autozine.org/technical_schoo ... gine_3.htm

Light Pressure Turbo (LPT)

Light pressure turbocharging is one of the most popular power boosting technology in recent years. Saab, the pioneer of turbo in saloons, is the first car maker put it into mass production. In 1992, it surprised many by introducing the Saab 9000 2.3 turbo Ecopower. The engine had only 170 hp, that is, just 20 hp more than the normally aspirated version and 30 hp below the standard 2.3 turbo. Basically, it was just the standard engine with a smaller turbo and lighter boost pressure.

While other car makers were still pursuing "on paper" peak power, Saab's clever engineers realised that less equals to more. Despite of lower peak power, light turbo engine remains to be strong in torque, thus aids acceleration. Most important, it has very much better drivability due to the inexistence of turbo lag. Throttle response is nearly instant. Besides, Saab proved that the better torque curve enables taller gearing, thus actually delivering better fuel economy that a normally aspirated engine of the same size !

In the past, poor drivability and fuel consumption prevent turbocharging from adopting in main stream sedans. Now the trend is reversed - due to the increasing requirement of safety and comfort, modern cars are growing every year. Heavier weight asks for more power. For many four-cylinder sedans, they have 2 choices: either upgrade to six-cylinder or add a light pressure turbo. Of course the latter is more cost effective. It need no more space, adds little manufacturing cost, and burns less fuel than a 6-pot engine, therefore many other car makers also adopted it.

[miniman82]

Check out this article......maybe GM was WAYYYYY ahead of their time! BTW, did you know that the Olds turbo used (what they called) "Turbo Rocket Fluid" as their water/alcohol injection? LOL Google it. And apparently there was a light on the floor shift console that illuminated when the tank went empty. Guess with 10.5 to 1 compression, the situation could be devastating!

People are still using alcohol injection to moderate detonation, I have a kit from Devil's Own to squirt methanol under pressure into the intake of my car. Haven't put it on yet, but it should save a lot of space over what an intercooler would take up.

Light pressure turbocharging is one of the most popular power boosting technology in recent years. Saab, the pioneer of turbo in saloons, is the first car maker put it into mass production.

And who owned Saab? That's right, GM did.

In 1992, it surprised many by introducing the Saab 9000 2.3 turbo Ecopower. The engine had only 170 hp, that is, just 20 hp more than the normally aspirated version and 30 hp below the standard 2.3 turbo. Basically, it was just the standard engine with a smaller turbo and lighter boost pressure.

These 16-valve engines used to have Garrett T3 turbos, now they have a smaller T25. Again, it likely goes back to fuel consumption and torque. People don't like turbo lag, it's a fact. I don't mind the lag so much, as long as the midrange is explosive.

Besides, Saab proved that the better torque curve enables taller gearing, thus actually delivering better fuel economy that a normally aspirated engine of the same size!

The same could be said of nearly any turbo engine. Turbos make massive torque, not HP. If sized correctly, it's often possible to make gearbox shredding power at very low RPM. Incidentally, it has been said that turbo engines having normal compression ratios (9:1+ range) often achieve better economy over a N/A engine of the same size, due to the pinwheeling compressor cutting pumping losses at part throttle. I've never been able to test this, as my right foot is always firmly planted to the floor.

I take a different approach. My view is the only purpose for adding a turbocharger is more power, so what stop short of the mark? I do it the traditional way, loose a point of static compression and blow hard. Turbo isn't fun till 14 psi anyway.

[Phil Dally]

This picture came from from a 215 thread on CCF.

[azdave]

Light Pressure Turbo (LPT)

Did that myself on a base model 98 Mitsu Eclipse. It was a stock high-compression 2.0 liter NA car (Chrysler 420A engine like in the early Neons and PT Cruisers, not the 4G63T). I added a 16G turbo that ran a max boost of 6 PSI. I added extra fuel with a rising rate FPR and did not need spark control or internal changes as long as I stayed in 5-6 PSI range. I had very good off-boost performance and fuel mileage plus I could just break into the 14's in the 1/4 mile. I was quite happy with the simplicity of the system and reliability. I got 36 MPG on freeway trips and could get full boost by 3000 RPM. Someday, one of these power plants may find its way into one of my Corvair chassis.

Just noticed...is that a Jetfire parked behind me?

[jensenracing77]

I just joined because i seen this thread and also interested in the Spyder. As for the Jetfire stuff, i just got one last January. We rebuilt the engine transmission and turbo/carb/injection systems. I see many questions above that can be answered at Jetfire.com. Olds used a small turbo with high compression thinking it would keep a greater throttle response for road enjoyment. there words were "we did not set out to build a race car but a street performer" .

the turbo/carb/metering system is a very complex system. I am getting much more comfortable with it and now understand more how the systems work. The fluid metering system with all it's safeties is the hardest part.

As for the Spyder... how many were made and anyone know if many are left? It is estimated that less than 50 Jetfires are left with the turbos and not likely over 100 left total between the 62 and 63 model years.

[cad-kid]

Welcome! Jensenracing77

I am pretty sure there are quite a few spyders left with the original setup still working. Others will chime in on the specifics. Post a pic of your jetfire and some of the underhood "goodies".

[jensenracing77]

This is our 62 jetfire. I finished putting it together in July/August. The body is original paint.

I need to browse the threads but how much boost did the Spyder have?

[flat6_musik]

Light Pressure Turbo (LPT)

Did that myself on a base model 98 Mitsu Eclipse. It was a stock high-compression 2.0 liter NA car (Chrysler 420A engine like in the early Neons and PT Cruisers, not the 4G63T). I added a 16G turbo that ran a max boost of 6 PSI. I added extra fuel with a rasing rate FPR and did not need spark control or internal changes as long as I stayed in 5-6 PSI range. I had very good off-boost performance and fuel mileage plus I could just break into the 14's in the 1/4 mile. I was quite happy with the simplicity of the system and reliability.

Hey, cool. My son's Nissan 240SX is running a N/A 2.4 liter 16 valve motor and he turbo'd it and is running about 12 psi of boost with a large intercooler. He hasn't had any problems and runs only premium fuel, no octane boost or water/methanol injection. I was amazed he could run that much boost with the factory 9.5 to 1 compression! He's run a best of 13.7 in the 1/4 mile and dyno'd out @ 275 approx. He beat me in my SRT-4.....I only did a 14.04.

[jensenracing77]

A note to the OP. I would be very interested in your red turbo. 62 jetfires had red and the 63 were aluminum color. From the date code on my Jetfire's turbo, i believe it was a service replacement and didn't get replaced with a red one. The red coting is $600 to have done so i went with aluminum. I even have an extra aluminum colored one i could trade.