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14

tl;dr: They do. It's just harder to tell how much. The longer answer is that they do and that effective compression is failing you as an approximation for actual effects. Think about detonation (AKA premature ignition of the fuel-air mixture). Normally we consider two causes: compression (the change in the space enclosed by the cylinder as the piston ...


13

As has already been noted, anything rubber will have perished and will need replacing, as will all the fluids and any other normal perishable items (brakes, battery, filters etc). The brakes will have siezed on, and depending how dry the garage was, the interior may have mould and the bodyshell may have gone rusty... The biggest risk, however, is that the ...


7

Let me lead off with an excellent book on the topic: Corky Bell's Maximum Boost. There is a sound treatment of the basics of turbocharger operation in addition to some dated and esoteric applications that are still interesting. For example, I find the discussion of turbocharging different types of carburetor to be of intellectual if not practical interest. ...


5

Sounds to me like the car is suffering from a boost leak - either the plumbing has a leak somewhere or the wastegate doesn't hold pressure properly. Does the car have a boost gauge and if it does, can you see if you're losing boost at the same time you get the noise? Normally you'll have a hard time hearing the wastegate if it's an OEM one as they all ...


4

You can't prevent the turbo from spooling up without physically removing it from the car. Depending on how the boost is controlled (ie, if there is a manual or electronic boost controller involved, too, or if it's just standard boost control by the ECU) you might be able to turn down the maximum boost to the pressure controlled by the spring in the wastegate ...


4

One of the reasons that a turbo setup with the equivalent effective compression is more forgiving of low octane gas than than a static compression setup is that you're not at that compression ratio all the time. Take that honda, for example. At 9:1 static ratio, you can run 87 octane all day as long as you don't push any boost at it. When you do start ...


4

The turbo shouldn't have any effect here after the first fraction of a second - a turbo runs off exhaust gases so with your foot off the accelerator it will spin down, and thus giving no forced induction. I don't know if there would be an effect with a supercharger, but I'm guessing not much. The difference in size will have an impact though 0.2 of a litre ...


4

If you have a highly tuned performance car you are told to idle for a few minutes before you roll up to the pump, otherwise you can destroy your turbo. I regularly see other tuned Japanese cars idling while i do this. It's also a good opportunity to talk cars with other petrolheads.


3

You'll need to check/replace for all rubber hoses(brakes, power steering, radiator, vacuum,...) as they could have dried and may break under load. Check wiring, they could have corroded or dried and can cause shortcut. Grease parts (Drifeshafts, steering, ...). Get a factory service manual for your specific vehicule and check the maintenance items, they ...


3

Two possibilities occur to me: a too-large turbo or a too-loose wastegate. when I press the accelerator there is no power until the rpm tachometer reaches 2500 This almost sounds like the replacement turbo is too large. when I press the accelerator there is no power until the rpm tachometer reaches 2500, then I need to release the accelerator ...


3

The letters are standard: Park Reverse Neutral Drive Sport (or possibly Snow - thanks @Brian) Braking (usually for going down hills) None of these have anything to do with 4WD or 2WD selection. If your Daihatsu is the 4WD version, it is permanently 4WD - there is no selector on that spec of car. It was a specific Japanese edition. You have stated ...


3

I wouldn't rule out a bad MAF so quickly - there was a generation of VW and AUDI MAFs that slowly went south without any indication from the ECU that they were doing so and IIRC the ECU managed to compensate for the dying MAF for a while. Also, if the ECU thinks you might be boosting at 15psi and using a conventional gauge suggests you're boost 7psi, you ...


3

I would suggest checking the owners manual to see what Sabb requires for a minimum octane fuel.It should be 93 octane for your motor.That being said higher octane fuel will not help the turbo last longer.Octane ratings are a measure of the fuels ability to resist engine knock.Engine knock is caused by fuel ignition with the piston in the incorrect ...


3

You should whenever possible let the engine idle for a short period of time to allow the turbo to cool in big trucks and cars alike. It will definitely add life to your turbo. If you are keeping relatively low speeds and minimal boost in the last few minutes of your drive such as in your neighborhood or long driveway then the time needed to allow the ...


3

The waste gate is designed (as you'll see in Bob's excellent answer to his linked question) to avoid spinning the turbo up unless needed. This saves fuel and wear. The blow off valve or dump valve is designed to stop a compression wave passing back into the turbo when you close the throttle, as this wave could stall the turbo completely, which can put high ...


3

In your case if it's diesel it has a turbo, if it's gas it doesn't. At least from the factory. Now that is specific to the year make and model in your question. As for what they look like. Nick has a good explanation. In this picture it's just to the left of the long green tube in the middle of the picture. That tube is connected to the turbo by a short ...


2

This is solvable at the ECU: one of the profiles that I could install using my AccessPort is called "valet mode." The performance is severely limited in that it prevents boost and significant speed. Caveat: going this route would cost you hundreds of dollars. Admittedly, I really like the performance aspect of the AccessPort and that's why I purchased it. ...


2

Any boost controller (manual or electronic) would allow you to turn down the boost. I have a DiabloSport unit and I can go way down almost to the point where the car is atmospheric (max. boost under 3 psi). When ready to restore it, flash back the original tune map.


2

In addition to good answer by @Bob: There are some tricks that can be used to ease the problem: A knock sensor for detecting premature detonations (and adjusting boost pressure). E.g. Saab APC allows safe use of lower octane fuels. Injecting water to cool the combustion chambers (instead of excessive fuel) Per cylinder exthaust thermometers (and ...


2

You pretty much guessed it, and if you didn't wikipedia is your friend. In summary, turbocharger operates by having two turbines connected to the same rotating axis. One turbine is spun by the exhaust gases, which cause the other turbine to spin. The second one is what forces the air into the intake of the engine. At idle rpm, there's barely any exhaust ...


2

They may have replaced the vacuum solenoids but it sounds like the wastegate still isn't opening smoothly. If you can see the wastegate, apply vacuum slowly to the vacuum line and see if it moves smoothly through it's motion, especially when initially opening. If not, it probably still needs cleaning. Under acceleration it needs the boost, but under ...


2

mikes is right: the octane is required for the engine, not the turbocharger on it's own. Said another way, the requirement for higher octane is a consequence of having a turbocharged motor vs. a normally aspirated one. We've discussed some of the associated issues before. Here is some relevant discussion on the subject: What are the benefits of premium ...


2

Have you checked for boost leaks, or rather the absence of them? It's very easy to put the various piping back together and it looks like it is fitted correctly, but you still might end up with a boost leak.


2

I can get you halfway; here's the formula for the effective compression ratio of a forced induction motor: Effective Compression Ratio (ECR) = sqrt((boost+14.7)/14.7) * Static Compression Ratio (SCR) So, for 5psi on your 9.9:1 SCR motor: ECR = sqrt(19.7/14.7)*9.9 = 11.46:1 However, I have had quite a difficulty trying to find a good way to get ECR to ...


2

I drive a gtc turbo and had the same problem. Check all the rear and front boost pressure/solenoids and their connecting rubber hoses and pipes....I spent lots on replacing parts, until I found a perished hose connector on the rear boost solenoid... never had a problem again... in fact I'm pushing 166kw on the wheels with no mods :)


2

The owner's manual for my turbo Eclipse specifically mentions cool-down time periods, with the times listed based on the type of driving that was done.


2

Both engines you mentioned have a supercharger and turbo combination. The performance difference is achieved by increasing the boost pressure to the engine. While this might be done only by using different ECU maps for small performance differences, the big performance differences usually require higher capacity parts as well, especially for the turbos, ...


2

Turbochargers look like large snails, and are fitted in the first part of the exhaust, between the manifold and the downpipe. They're often paired with an intercooler, which looks like another radiator... The Wikipedia page for the Suburban suggests that only the Diesel version of the ninth generation were so fitted (which seems odd from a European ...


2

The only cars with turbocharges which do not have air filters are race cars. They do it this way so there is absolutely no restrictions on the intake tract. Race engines are routinely rebuilt as needed, so are not worried about small particulates entering the engine. Normal street driven vehicles will all have air filters on them, and as long as those air ...


1

Turns out the previous owner of the car adjusted the wastegate actuator in an attempt to increase boost pressure. The sudden loss of boost came about because the ECU forced the wastegate open in an attempt to keep the manifold attached to the engine ;) Kudos to whomever wrote the software for the Bosch Motronics unit.



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