Fuel Turbo Corvairs

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NorwayCorvair
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Fuel Turbo Corvairs

Post by NorwayCorvair »

What fuel do you guys run on your turbo Corvairs?
Wonder what Octane you use and such.
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Re: Fuel Turbo Corvairs

Post by terribleted »

I run the best we can get here in all Corvairs which is 92-93 octane (our premium fuel). Lesser grades 89 or 87 octane are asking for trouble in my opinion....more prone to detonation etc. , particularly in a high performance Vair engine like a turbo or 140.
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Re: Fuel Turbo Corvairs

Post by miniman82 »

Pump 91 at a minimum, that's what they had in California. Here I have pump 93 which is much better, but I always throw in a bottle of booster just to be on the same side.
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Re: Fuel Turbo Corvairs

Post by notched »

I run 93 and run a Snow alcohol/methanol injection that turns on above 4 lbs of boost
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Re: Fuel Turbo Corvairs

Post by NorwayCorvair »

Leaded or unleaded?
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Re: Fuel Turbo Corvairs

Post by bbodie52 »

Leaded or unleaded really does not matter, since the valve seats in the Corvair engine were already treated to deal with the air cooled environment. The lubricating factor offered by leaded gasoline had no real impact on the Corvair.
Wikipedia wrote:Valve wear preventative
Tetraethyl lead works as a buffer against microwelds forming between the hot exhaust valves and their seats. Once these valves reopen, the microwelds pull apart and leave the valves with a rough surface that would abrade the seats, leading to valve recession. When lead began to be phased out of motor fuel, the automotive industry began specifying hardened valve seats and upgraded exhaust valve materials to prevent valve recession without lead
:link: https://en.wikipedia.org/wiki/Tetraethyllead
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Re: Fuel Turbo Corvairs

Post by NorwayCorvair »

Im running the norwegian 95 octane so then i aint doing nothing wrong :clap:
Thinking about starting to put 98 in it
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Re: Fuel Turbo Corvairs

Post by bbodie52 »

:angry: The Corvair turbocharger system is a 1962 design that was intended for use in an economy car. There were no inter-coolers, water injection systems, waste gates, or electronic sensor computer-controlled anything! The only thing that prevents an engine meltdown is turbocharger design boost limitations, a pressure-retard timing control on the distributor, a low compression ratio in the combustion chamber, and PREMIUM HIGH-OCTANE FUEL!

Even so, the system does not tolerate sustained, long-duration full-boost operation. Turbocharged boost operation was really intended for short periods of acceleration in this engine. I found this out once when I was driving my turbo Corsa up a long hill on the Ventura freeway while enjoying giving it full throttle for long periods on a hot day. A hole in one of my pistons was the end result!
:sad5:
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Re: Fuel Turbo Corvairs

Post by rv6aaviator »

Premium 91 to 93 octane is standard for me. The car loves to have a bottle of octane booster added.

If I don't add octane booster, I will add 3 or 4 gallons of Avgas - 100 octane mixed in with a tank of premium 91 to 93 octane fuel. Spyder runs like a scalded dog!!
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Re: Fuel Turbo Corvairs

Post by bbodie52 »

Historical Perspective...

This 1971 article was written during the transition from leaded to unleaded gasoline. According to the article, REGULAR gasoline octane ratings were in the 94-96 range, and PREMIUM fuel octane was 99-100!

Popular Mechanics Feb 1971
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Gasoline though the years

Ok this is what I have hunted down for the U.S. First two different post from people who might or might not know what they are talking about and then i do a second post from a source I would trust more.

#1 http://www.stevesnovasite.com/forums/ar ... 64646.html

#1 The History of Gasoline Octane

As the high compression engine era was gaining steam in Detroit during the early to mid 1950s, the need for higher octane gasolines was becoming more and more apparent. When automobile production resumed in 1946 following World War II, gasoline octanes in the United States averaged at 79 for regular and 85 for premium and those numbers climbed year after year until 1954, when premium gasolines were rated as high as 94 octane and regular at 86. Oil companies were promoting their gasolines, especially their premium grades, with claims that their fuels increased power and gas mileage while cleaning out the carburetor and other engine parts to wash away accumulated carbon and other deposits while regular usage prevented the future buildup of such. Among the additives widely promoted by leading oil companies were Texaco Sky Chief with Petrox, Super Shell with TCP, Mobilgas Special with a Double Compound ingredient and Sinclair's Power-X featuring a nickel additive.

As Detroit continued the horsepower race unabated in the mid-to-late 1950s, the oil industry responded by continuing to increase the octanes of their gasolines, and a few even went the extra mile by introducing "super-premium" fuels which were even higher in octane that the premium grades. In 1956, Sunoco introduced its "Dial A Grade" blending pumps that could dispense five different grades of gasoline, later increasing to eight, ranging from subregular Sunoco 190 to superpremium Sunoco 260. That very same year, Esso introduced a third grade of fuel called Golden Esso Extra, which came in a gold pump and had an octane rating of just over 100. That was followed in the spring of 1957 by Gulf, which introduced its super-duper Gulf Crest that was dispensed from a purple pump, and Chevron debuted its Custom Supreme grade in the western states.

By 1958, oil companies generally took a position concerning the number of gasoline grades offered with the greatest majority choosing to stick to just two (regular and premium) and simply increasing the octane ratings of both grades of gas with the premium fuels coming very close in octane to the super-premiums offered by some competitors. That year, regular gas averaged at about 90 octane and premium hit the 98-99 mark. With compression ratios on Detroit's hottest engines reaching the 10 to 1 plateau and higher, nearly half of all 1958 automobiles were powered by engines requiring premium fuel. And that included virtually all medium and higher-priced automobiles, leaving only a few lower priced cars powered by engines capable of using regular fuel including most Ramblers and Studebakers, as well as Ford, Chevrolets and Plymouths with standard six-cylinder or small V8 engines.

But the advent of smaller compact cars with more economical engines, both domestic and foreign, along with detuned engines in some larger cars, slowed down the octane race a bit and by 1961 only one-fifth of new cars were powered by engines that required premium or super-premium gasolines. Motor Trend magazine noted the trend toward economy that year by pointing out that Chrysler Corporation had reduced compression ratios across the board on standard engines to burn regular gas, a move that may reduce miles per gallon fractionally but give you more miles per dollar. "Five years ago, new car buyers swallowed premium gas as a necessary evil; today a salesman has to have a good reason for specifying it."

With a smaller proportion of new vehicles on the road requiring high-octane gasolines and the octane ratings of both regular and premium grades continuing to climb, demand for the more expensive super-premium grades, never really that high, dropped dramatically. In the fall of 1961, Esso and Gulf both discontinued their super-premium grades of fuel in favor of lower octane fuels to supplement their regular and premium offerings. Esso increase the octane of its premium Esso Extra and introduced a new middle grade of gas, Esso Plus, which was inserted in price and octane rating between Extra and their regular fuel. Gulf took a different direction by replacing its super-premium Gulf Crest with a new sub-regular product, Gulftane, which was priced about one or two cents less than its Good Gulf regular - and also designed for vehicles that could use gasolines with octane requirements lower than regular grades. In the process, Gulf created a subregular product that was priced on par with regular gasolines offered by cut-rate independent gas stations that generally sold gas for a few pennies less than major-brand stations - sparking off "gas wars" in many areas of the country where prices often dropped as low as 18 cents per gallon for regular and subregular grades (compared to the prevailing normal regular fuel price of 25-26 cents per gallon).

As the subregular and middle grades of gas came to market in 1962, the average octanes of gasolines in the U.S. now stood at 93 for regular, 99 for premium and 102 for the few super-premiums still left on the market. Those numbers would increase only slightly in the next few years to around 94 octane for regular, and 100 for premium by 1967.

By this time, other oil companies jumped on Sunoco's bandwagon by offering blending pumps dispensing several grades of gasoline from one pump to tailor fuels to a particular vehicle's octane requirement. Signal Oil Co. offered seven different grades of gasoline through its blending pumps at its Hancock and Norwalk stations in the Western United States. In the Mid-Continent region, Conoco began testing four-grade blending pumps in some markets in 1965 and introduced the concept throughout its marketing area two years later. In addition to Regular and Premium, Conoco offered its sub-regular Conotane (similar to Gulftane) and a Super grade between Regular and Premium similar to Esso Plus. A similar four-grade pump setup was offered by Skelly that included Skeltane (sub-regular), Regular, Special (intermediate) and Keotane (premium).

The development of true high-octane gasolines came to a screeching halt (along with the musclecar era) as a result of the Clean Air Act of 1970, which stipulated many federal mandates for automakers to reduce emissions of their engines. With that, General Motors President Ed Cole announced that his company's engineers found the answer to meet these ever toughening standards - a catalytic converter, which got the job done but required the use of unleaded gasoline. As a first move toward the 1975 models that would be equipped with such devices, GM reduced compression ratios on all of its 1971 engines to permit the use of low lead, regular leaded or unleaded gasolines and other automakers soon followed. This move spelled the end of the "octane race" and as unleaded gasoline was being phased in at most U.S. service stations during 1974 in time for the 1975 and later models that would require such fuels, the higher-octane premium and super-premium leaded fuels gradually disappeared from most stations - leaving only lower-octane leaded regular and unleaded grades. By the late 1970s/early 1980s, the last of the leaded premium grades disappeared as oil companies introduced new premium unleaded fuels that were higher in octane than the unleaded regular fuels (91-83 vs. 87) - but still lacked the moxie of leaded premium fuels, leaving drivers of older cars with engines requiring high-octane gasolines with few options to keep their classic rides intact without undue engine knock, creating a cottage industry for octane boosters and, with the recent phaseout of leaded gasoline altogether, additives to replace lead as a lubricant against valve recession.

#2 http://www.stevesnovasite.com/forums/ar ... 64646.html

#2 By the way, the 93 octane of today is actually not that much less octane than the octane of the Premium pump gas of the 60's and early 70's.

Here is why:

I used to work for Hess Oil company back then. As many of you may remember, 100 advertised octane was common and Hess even had 101 octane for a few years. Sunoco260 gasoline was 102 octane. Those octane ratings sound very high compared to today's octane ratings, but they were not as much higher as you would think. That's because the advertised octane back then was based on a different measurement than we use today. The reason is that there are 2 ways to rate octane. One is called the "research" octane number and the other is called the "motor" octane number.
The research octane number is a higher number than the motor octane number, so when oil companies used to advertise their Hi-Test gasoline, they used the more impressive research octane number, in this case, around 100 octane.

But "motor" octane is a number about 10 points lower than the Research number. The oil companies didn't advertise that lower number.
In the early 70's, the government decided to require oil companies to post an average of the 2 different octane ratings, which lowers the octane rating number for the same fuel that had higher numbers before. So, ever since then, when you look on a gas pump, you'll see a sticker for the octane rating that says "R+M/2", which stands for Research octane plus Motor octane divided by 2, which is the average of both rating numbers.
Therefore, the old Premium from the 60's, that was 100 Research octane, also had a Motor octane rating of about 90. So that same old 100 octane Premium would today now be posted as an average of 100 Research octane and 90 Motor octane, and would be 95 octane. That's still a little higher than the 93 octane of today's Premium, but not as big a difference as most people think.

In 1975, all NEW cars had to use Unleaded Only fuel. It became against the law to put leaded fuel in an unleaded car. Unleaded gas prices were a little higher and some people would try to put leaded gas in their car to save a some money. There were adaptors sold so you could adapt the larger leaded gas nozzle to the smaller hole of the unleaded gas filler. Some people just cut the hole bigger, so the larger leaded gas nozzle would fit. Attendants were asked to put leaded gas in unleaded cars sometimes and the customer would get mad when the attendant said it was against the law for them to do so. Anyway, the stations had to convert gas pumps to unleaded gas, change the nozzles, the signs, etc. The stations still sold leaded gas too for a while, and still had some of the higher octane premium leaded fuel for earlier cars that were allowed to run leaded gas. It would've been rated at about 94 or 95 octane, because of the new R+M/2 octane rating system. Gradually, leaded fuel was phased out though, and I think it was only a year or so before you could only get unleaded.

Probably more than you wanted to know, but some might find it interestin
The methods for measuring the anti-knock characteristics for gasoline has changed since the 1970s, and methods vary in different countries, as well. If you want to really get confused, try reading the Wikipedia article on octane rating!

:link: https://en.wikipedia.org/wiki/Octane_rating

In any case, lead-free fuel, different blends and measurement techniques, and the introduction of alcohol-based Ethanol all add to the confusion with regard to anti-knock characteristics, energy content, and chemical breakdown as the fuel ages. Even the altitude can impact the anti-knock characteristics of the fuel. Increased alcohol content can even damage older engines and fuel systems.

With regard to the best fuel for a Corvair — especially a turbocharged Corvair — the consensus seems to be for the owner/driver to be alert for signs of detonation (pinging and knocking) with the engine under load. Stay away from E85 ethanol, and be aware of the tendency of 10% ethanol to break down and to absorb water from the air more quickly as it sits in the tank. With the turbocharged Corvair especiaslly try to get the highest octane Premium available, and be cautious as you apply turbocharged boost to your Corvair.
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Re: Fuel Turbo Corvairs

Post by Scott V »

bbodie52 wrote:This 1971 article was written during the transition from leaded to unleaded gasoline. According to the article, REGULAR gasoline octane ratings were in the 94-96 range, and PREMIUM fuel octane was 99-100!
the octane rating was different. 100 old octane rating is like 94-95 octane now.

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Re: Fuel Turbo Corvairs

Post by miniman82 »

bbodie52 wrote:The only thing that prevents an engine meltdown is turbocharger design boost limitations, a pressure-retard timing control on the distributor, a low compression ratio in the combustion chamber, and PREMIUM HIGH-OCTANE FUEL! Even so, the system does not tolerate sustained, long-duration full-boost operation. Turbocharged boost operation was really intended for short periods of acceleration in this engine. I found this out once when I was driving my turbo Corsa up a long hill on the Ventura freeway while enjoying giving it full throttle for long periods on a hot day. A hole in one of my pistons was the end result!


Lots of misinformation here, I will attempt to clarify.


The turbocharger is NOT what sets the amount of boost pressure applied to the engine (nor is the muffler), that was controlled by careful design of the carb throat. It will only allow so much air to pass through it till it acts as a restriction, thus limiting the amount of boost the turbo can create because the carb is before the compressor in a draw through system. This can be proven by replacing the YH with just about any other carb, and watching the boost gauge climb until the engine destroys itself. I will admit that the 150 engines had a stupidly small compressor wheel, but even those are capable of more- just not a whole lot more.

Your experience of holing a piston on a hot day with boost is typical, but that doesn't mean the engine is weak or cannot handle extended periods of boost. 2 things are important to remember with all Corvair engines, not just the boosted ones:

1. They are cooled by air, which means they are far more sensitive to outside air temps than a waterpumper

2. Because they tend to run hotter (head temp wise), the margin for detonation is also much slimmer vs a waterpumper

These 2 simple facts are what get a lot of people in trouble. Not knowing what detonation sounds like or being sensitive to how the engine behaves has a lot to do with it as well. That said I've driven my 180 in all types of weather, both desert heat and Wisconsin -5*F winters. One thing has always been true- it LOVES cool air! The things that it simply would not do when it's hot out it would tolerate all day long when it was nice and cool. Example:

In California I tried to dyno the car, temps were around 95 that day. It made only 95hp to the wheels, and I couldn't get more than 3 lbs of boost out of it due to uncontrollable detonation.

When I moved to Illinois, outside temps during fall hovered in the low 60's. I found I could stand on the gas through every gear at max boost continually, and the more I did it the better it ran.

Not only that, but I was able to add timing when the temperature dropped outside leading to more power and better response. Why? Because cool air removes waste heat from the engine a lot better than hot air does, there's really no other reason than that.
With regard to the best fuel for a Corvair — especially a turbocharged Corvair — the consensus seems to be for the owner/driver to be alert for signs of detonation (pinging and knocking) with the engine under load.
AND DON'T TRUST THE PRESSURE RETARD! I have yet to come across one that did what it was supposed to do 100% of the time, they are far to inconsistent for me. That (and breaking starter noses from overly advanced base timing) was enough for me to put a programmable ignition system on the car, and I haven't looked back since.
Stay away from E85 ethanol
UNLESS YOU KNOW HOW TO TUNE, in which case E85 will be the best thing you can possibly fuel your turbocharged engine with. No, don't just go to a filling station to put E85 in the tank and expect it to work- because it won't. But if you increase the jet sizes accordingly and verify with wideband oxygen sensor, the engine will run better than ever due to the cool running of the alcohol and increase in octane rating. You can typically add more timing too, because alcohol burns slower than gasoline. Yes you will lose MPG because it has less energy in it, but from a pure fun standpoint nothing is better for turbo engines- unless your fuel system can handle pure methanol of course.
be aware of the tendency of 10% ethanol to break down and to absorb water from the air more quickly as it sits in the tank. With the turbocharged Corvair especially try to get the highest octane Premium available, and be cautious as you apply turbocharged boost to your Corvair.
Maybe if you let it sit for a whole year, but for the driven Corvair it's not an issue. Think about it- what are you putting into your modern car/truck tank?

Lastly: TUNING TUNING TUNING! If you don't have any experience tuning a turbocharged engine, you really ought not to be messing with a Corvair 150 or 180. Anything that can go wrong with a modern turbocharged engine can go wrong twice as fast in an air cooled Corvair, which makes the learning curve that much steeper. They will tolerate slight amounts of sporadic detonation just fine on boost, but will melt a whole lot faster than your Honda if allowed to go on. Once dialed in, you should have no worries about getting on it whenever it suits you. In my opinion that's what owning a turbo is all about. :assault:
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Re: Fuel Turbo Corvairs

Post by bbodie52 »

:goodpost: I cannot argue specifically with the technical caveats that are put forward here, except that they are written with technical exceptions that many turbocharged Corvair owners would probably not be aware of. A turbo expert can certainly pick my comments apart — but I was trying to make a point that it is easy to exceed the capacity of the turbocharged Corvair engine to protect itself. The integrated design safety margins in a stock turbocharged engine leave little room for error. Inadequate fuel octane, high ambient temperatures, possibly a faulty (unsophisticated) pressure retard device, improper tuning, etc. coupled with hard use (such as long periods of full boost on a hot day while climbing a lengthy uphill grade) can place your engine on the road to disaster (especially when the car is being driven by an inattentive 18 year-old who is not listening for signs of detonation). Modern turbocharged engines are much-more sophisticated with computer controlled systems and engine sensors that will monitor many operating parameters and will change timing, boost, and fuel injection settings to protect the turbocharged engine in ways that far exceed the capabilities of the vintage turbo Corvair package.

When I mentioned integrated design boost limitations of the Corvair turbo, I meant the complete system — from intake carburetor to tailpipe. Certainly the turbo itself can pump more air if the stock carburetor is replaced with a Weber DCOE or some other carburetor that can flow more air! But that is beyond the scope of my original comments. A person who is knowledgeable about turbo Corvairs would likely know about proper tuning, proper high octane fuel, and safety limitations of the stock system that would make him cautious about full boost operation. He would also be continually monitoring the engine for signs of detonation, while the average owner might not. At 18, I was not a cautious or well-educated owner. I just pushed it too hard and was oblivious to what might be going wrong with my engine — until I hit a "hole in one" and had to pull over and call my mother — asking her to rescue me and to bring a tow bar so that I could tow the sick Corvair home!

As for E85 ethanol — it should not be used in a Corvair. A tuning expert might be able to modify a turbo Corvair fuel system to take advantage of the higher effective octane capability of this alcohol-based fuel. But that is not for the amateur who might try a tank full of E85 without realizing all of the issues involved. The low energy content of E85 can mean a 25-30% reduction in fuel mileage! Even 15% Ethanol is not approved for cars built before 2001, and E85 has a much greater alcohol content than E15! A 1960s turbo Corvair is hardly a "flex-fuel" vehicle that is capable of tolerating E85 fuel! Ethanol is hygroscopic, which means it absorbs water more easily than gasoline. The combination of E85 alcohol-based fuel with some water content buildup in an older classic car can lead to corrosion and damage to the fuel tank, fuel lines, rubber fuel hoses, etc. The Corvair fuel system is simply not designed or built from materials that can tolerate E85 fuel.

Dont trust the pressure retard? Absolutely true. But it is one of the few systems that Chevrolet included to try to protect the engine from detonation. The fact that it is unreliable and not always effective is of little comfort. And there is no sensor or warning light to tell you that it is not doing its intended job and that your engine is detonating. In my case the sudden loss of power and a hole in a piston was my only 'warning".

Turbo Corvair owners will benefit from reading and asking questions about their engine, and a knowledgeable owner is more-likely to pick up on signs of problems with their engine. The turbocharged Corvair engine can be a lot of fun, but the knowledgeable owner who properly tunes and maintains the engine is way ahead in getting the most from the turbocharged engine.
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Re: Fuel Turbo Corvairs

Post by Scott V »

miniman82 wrote:Lots of misinformation here, I will attempt to clarify.

The turbocharger is NOT what sets the amount of boost pressure applied to the engine (nor is the muffler), that was controlled by careful design of the carb throat.
both the carb & the muffler sets the amount of boost pressure applied to the engine. simple test. remove the muffler & see the boost pressure increase.
miniman82 wrote:Not only that, but I was able to add timing when the temperature dropped outside leading to more power and better response. Why? Because cool air removes waste heat from the engine a lot better than hot air does, there's really no other reason than that.
no other reason? what about cold air is denser than hot air. denser air = more power cuz you can pack more o2 into the engine. you can run more timing w/denser air cuz the denser mixture will tolorate more timing for a few reasons - all related to temperature.

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Re: Fuel Turbo Corvairs

Post by bbodie52 »

Many of these ideas and concepts, such as a larger carburetor to increase turbocharger boost capability, the use of E85 to take advantage of its higher effective octane and anti-detonation characteristics, cooler intake air to permit an increase in timing (as might be done if you had computer-controlled ignition and fuel systems with engine sensors that would optimize timing based on changing ambient temperatures) and having such a computer-controlled system that would detect detonation with sensors and would adjust ignition timing and other engine parameters instead of relying on a "dumb" pressure retard device simply appear to point to limitations in the 1960s Corvair design that lacks newer and improved technologies that have been developed since then.

All of these comments would seem to point right back to the limitations in the stock turbocharged Corvair design that can haunt the turbo Corvair owner — especially if that owner is unaware of the limitations of the older design. Newer turbocharged cars do a better job of managing and optimizing the engine as driving conditions change. The owner can let the technological advances take care of "tuning" the engine on the fly, without having to be too concerned about pushing the engine too hard or the potential for engine damage that could result. My original comments were intended to warn the turbo Corvair driver of the limits in the stock turbo Corvair design. I was simply trying to point out that many of the newer engine technologies that have become expected and commonplace were not included in the Corvair design. Maximum boost was limited by the intake system design. Timing control was very rudimentary. Ambient temperature changes and a variation in the octane rating or quality of the fuel could have a significant negative impact on engine operation. The Corvair owner who is aware of these limitations and hazards is more likely to drive with caution and might be more-sensitive to performance and operational changes that might be a warning sign that the engine is getting into trouble.
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Re: Fuel Turbo Corvairs

Post by miniman82 »

Scott V wrote:both the carb & the muffler sets the amount of boost pressure applied to the engine. simple test. remove the muffler & see the boost pressure increase.

If that happened on your car, you had the wrong muffler. My car saw no increase in performance or rise in boost from running sans muffler, the only thing that got increased was the noise level. Think about it: if the muffler makes enough of a restriction in breathing as to limit boost pressure, you've got a problem. GM didn't have a lot of tuning available with the low tech they had, but I seriously doubt they would resort to sticking a potato in the exhaust...
no other reason? what about cold air is denser than hot air. denser air = more power cuz you can pack more o2 into the engine. you can run more timing w/denser air cuz the denser mixture will tolorate more timing for a few reasons - all related to temperature.

With regard to power production sure, but it's not a huge difference. I was speaking just above that on the merits of cool air allowing you to run WOT for extended periods, the engine being cooled enough to tolerate such operation trumps any bump in power from more dense air since you wouldn't be able to enjoy any of it to that level when it's hot. You simply can't run it the same way when it's hot outside, that's the point I'm making. It's cylinder head temperature that makes it all possible, I've noticed that it works the best when the dash gauge reads just shy of 300. Any colder than that and it's really not up to temp, much hotter and you're getting into detonation territory with extended runs. The break point for my engine tends to be around 72* OAT, when it's lower than that I can drive it as hard as I want for as long as I want without issues. Warmer than that, it will start bitching when you push it hard.

This assumes you have the correct timing, high octane fuel and dead on AFR's- 99% of turbo Corvair owners are blissfully unaware of any of these parameters, and will be happy to be able to get into boost every so often so long as it doesn't grenade (which is a shame of course, because this engine is capable of MUCH more than the factory intended). I'm can't stop unless it drives more like a modern car, which is why the YH and distributor had to go- they are not up to the task IMO.
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