91 jetta deisel add bigger turbo?

[Nona]

I recently purchased a 91 Jetta Deisel. 1.8 engine, for prep purposes.

I also purchased a used 85 turbo to increase horsepower and is larger than the 91's turbo.

The question is: do I have to add a 84 or 85 fuel injector pump with an annoid on it or can I increase horsepower with just the "new" 85 turbo.

Thanks for your input.

 

[dieseltrooper]

I don't have a ready answer, but let me ask if the 91 is already a turbo? If not, do some digging amd talk to a VW diesel tech. I recall that you could not just bolt on a turbo because the pistons on the non-turbo are not rated for the extra load. You might be looking at a full swap.

 

[CTCStrela]

Nona, no need to put the larger turbo on. If it is an intercooled engine, or even not, it just takes a bit of tuning.

Raise the boost on it by say 2lbs, and have it (if it is mechanically injected) retuned for that boost level.

 

[Opus Dei]

Turbochargers are something that needs to be "sized" for the application. There's a lot to factor in-compression, intake size, fuel metering, etc. Turbos are tailored for applications, also-like altitude compensating on airplanes. The wrong size can mean too much volume or pressure into the engine. Too big, and it takes too long to "spool-up", meaning poorer throttle response.

The older car might have lower compression, different intake, etc. to enable using the larger turbo. It doesn't necessarily mean it'll go faster. I would look into what Strela said, or see if there's a performance chip or programmer for the car.

 

[Kamelot]

Also if your increasing horsepower arent you loosing something? Like gas mileage? They make about 44 to 48 mpg now stock. Might be worth checking out just in case. I hope ive added something useful to this. I have a volkswagen just not a diesel yet.



Kamelot