Just out of curiosity really, what is the difference between the turbos used on petrol and diesel cars?
What would happen if you were to use a diesel turbo on a petrol engine and vice versa?
If you wanted a big turbo, what would happen if you decided to bolt on a turbo out of a lorry?
Like I've said, just curious that's all!

 

If you bolt a big turbo on. No doubt you will have loads of lag. The pistons would need to be changed to i would of thought.

 

Some people do use truck turbos, there have been some bonkers euro builds using them. Historically the diesel turbo's used different materials as the exhaust gas temperature is lower compared to a petrol equivalent whether this still applies I do not know, but lots of diesel turbo's are not watercooled where as the majority of oem petrol units are.

We have a truck turbo in the workshop and it is just silly big, like snap your manifold off big

 

The bigger the turbo the longer it takes to spool up too, so a truck turbo would spool up at about 5000 revs on a cossie engine, and then you wouldn't get full potential out of it as you'd run out of revs

 

The biggest turbo I have seen was for a marine engine , it was massive!

 

Bearing in mind a diesel engine produces its power at a lower RPM, their turbos are designed accordingly, so the common misconception that a big ass truck turbo will create huge amounts of lag simply isn't accurate.

Why do you think us Volvo boys use honking Holsets from big 6+ litre Cummins diesels?!