SLEEPER
Pro Tuner
- Points
- 592
First let me make clear what this is.
It is not a detailed account of how to fit a turbo to any particular car.
It is an attempt to explain that fitting a turbo to an NA engine isn’t simply a bolt on job
Hopefully it will explain what you need to know if you are thinking of doing this and how to choose the right turbo ( No any one wont do )
It isn’t meant for fully qualified mechanics or tuning gurus and has been kept pretty basic for that reason. If you are either of those this thread wont tell you anything .
I’m also not going to explain the ins and outs of how a turbo works because that isn’t the what the thread about.
OK so you have not been put off yet and are still determined to fit this turbo then read on………
Before a turbo is fitted it is essential to check that the engine is capable of running the extra power.
A lot are not without mods.
More power needs more fuel so the fuel system will almost certainly need to be uprated . Also the head has to be able to flow the extra gases or it will be mostly all be for nothing
Then the power gain and extra heat due to the higher boost level mean that some engine parts may not take the strain.
Rods , pistons and especially head gaskets are not always up to the job. The compression may also have to be lowered but again it depends on the motor and again this thread isn’t for any specific engine.
There are unfortunately no set rules because different engines can support different levels of power before needing work. A 1jz supra engine for example can double the stock bhp pretty safely while some will surrender after the smallest increase.
This info needs to be checked . I make no attempt to provide such a list because again this is a general thread. That doesn’t mean it isn’t important . IT IS VERY !
By very I mean that if the engine surrenders it could be a head gasket or holed piston or worse
But for now we will assume that the above has been sorted or is ok to start with.
Now you need choose a turbo.
They come in all sizes and you need one that will work with the engine not just one that is nice and shiny .
Turbos are driven by exhaust gases and produce little or no power until working at the right level
They spool up at different speeds - the larger the turbo the slower it spools because the vane being turned is larger so needs more air to do this
On the other side a bigger engine produces more exhaust gases that a smaller one so will spool up a given turbo quicker that a smaller engine at the same revs.
To make matters worse different turbos max out ( run out of steam) at different levels as well which may not suit your engine .
This information can be checked by looking at the turbos compressor map . These are easily found on the net .
They can be quite difficult to understand so the best bet is to see if your engine was ever turbo’d out the factory .If not look on the specialist forums for your car or cars with the same engine. If its possible someone will have already done it . The advantage of this is simple - you can get a list of the other parts that you need and know they will fit ( and work)
You also need to check the maximum boost level that the chosen turbo will safely run at.
Yes turbos can carry on producing more power up to their max out level but the vanes can break if the boost level is too high (for them ). They broken vanes will either go out the exhaust (if you are lucky) or go through the engine (if you are not ) with the latter you could easily destroy most of the engine.
A final mention on twin turbo set ups ………if you needed to read this post stay away from them
Most use a small turbo to start off and then a larger turbo that comes in later . They are notoriously difficult to match and often there is still some lag inbetween. So don’t even think about this unless the engine had this out the factory (eg some Subaru’s)
A few engine (some skylines for example ) run two turbos coming in together but it really isn’t worth looking at this set up unless the engine is at least 2.5 litres and then unless its been done before I would just fit a single turbo.
It is not a detailed account of how to fit a turbo to any particular car.
It is an attempt to explain that fitting a turbo to an NA engine isn’t simply a bolt on job
Hopefully it will explain what you need to know if you are thinking of doing this and how to choose the right turbo ( No any one wont do )
It isn’t meant for fully qualified mechanics or tuning gurus and has been kept pretty basic for that reason. If you are either of those this thread wont tell you anything .
I’m also not going to explain the ins and outs of how a turbo works because that isn’t the what the thread about.
OK so you have not been put off yet and are still determined to fit this turbo then read on………
Before a turbo is fitted it is essential to check that the engine is capable of running the extra power.
A lot are not without mods.
More power needs more fuel so the fuel system will almost certainly need to be uprated . Also the head has to be able to flow the extra gases or it will be mostly all be for nothing
Then the power gain and extra heat due to the higher boost level mean that some engine parts may not take the strain.
Rods , pistons and especially head gaskets are not always up to the job. The compression may also have to be lowered but again it depends on the motor and again this thread isn’t for any specific engine.
There are unfortunately no set rules because different engines can support different levels of power before needing work. A 1jz supra engine for example can double the stock bhp pretty safely while some will surrender after the smallest increase.
This info needs to be checked . I make no attempt to provide such a list because again this is a general thread. That doesn’t mean it isn’t important . IT IS VERY !
By very I mean that if the engine surrenders it could be a head gasket or holed piston or worse
But for now we will assume that the above has been sorted or is ok to start with.
Now you need choose a turbo.
They come in all sizes and you need one that will work with the engine not just one that is nice and shiny .
Turbos are driven by exhaust gases and produce little or no power until working at the right level
They spool up at different speeds - the larger the turbo the slower it spools because the vane being turned is larger so needs more air to do this
On the other side a bigger engine produces more exhaust gases that a smaller one so will spool up a given turbo quicker that a smaller engine at the same revs.
To make matters worse different turbos max out ( run out of steam) at different levels as well which may not suit your engine .
This information can be checked by looking at the turbos compressor map . These are easily found on the net .
They can be quite difficult to understand so the best bet is to see if your engine was ever turbo’d out the factory .If not look on the specialist forums for your car or cars with the same engine. If its possible someone will have already done it . The advantage of this is simple - you can get a list of the other parts that you need and know they will fit ( and work)
You also need to check the maximum boost level that the chosen turbo will safely run at.
Yes turbos can carry on producing more power up to their max out level but the vanes can break if the boost level is too high (for them ). They broken vanes will either go out the exhaust (if you are lucky) or go through the engine (if you are not ) with the latter you could easily destroy most of the engine.
A final mention on twin turbo set ups ………if you needed to read this post stay away from them
Most use a small turbo to start off and then a larger turbo that comes in later . They are notoriously difficult to match and often there is still some lag inbetween. So don’t even think about this unless the engine had this out the factory (eg some Subaru’s)
A few engine (some skylines for example ) run two turbos coming in together but it really isn’t worth looking at this set up unless the engine is at least 2.5 litres and then unless its been done before I would just fit a single turbo.
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