Tuning guide for 200/400 non-intercooled cars
Generally these cars are the cheapest to tune however they reach some component limits so I’ll describe how I’d tune the car and list some arbitary budgets in mind to spend on it and what you may achieve. I’ve assumed at each stage that all the previous stages have been done. These are my own views and so other people may disagree. Read up and make your own decisions.
Step 1 –
Follow the tuning guides on this forum for tweaking the fuel and tweaking the boost level to give you a reasonable performance increase for no outlay.
Power achievable ~100bhp/200ftlb
Step 2 –
Add a decat to remove the catalytic converter and this’ll improve the turbo spool a little.
Cost £0 to £~50
Power achievable ~110bhp/200ftlb
Step 3 –
Add an intercooler – from an intercooled model (you’ll need the intercooler, the metal pipes, the rubber boost hoses, and the inlet manifold). This is usually most cheaply sourced from a scrap yard.
You can also add an aftermarket intercooler but this is likey to be at a higher cost
Power achievable ~120bhp/200ftlb
Step 4 –
By now, if not before then you’ll have reached the limit of the standard clutch. You could replace this with some super-duper performance clutch but the best bang for buck upgrade is the standard intercooled model clutch from the 200/400/600/25/45/zr/zs diesels, (they are all the same). The non intercooled clutch is 215mm in diameter, the intercooled models are 228mm in diameter and are usually good for ~250ftlb.
To fit this clutch you can either have your original flywheel drilled and tapped for the larger diameter clutch plate, or you can fit a flywheel from an intercooled model. This sometimes involves a little alteration spacing the crank sensor out further from the flywheel using washers but it is achievable. I’ve assumed a scrap flywheel from a Di has been used and a new reasonable spec clutch plate.
Budget – £150-200
Power achievable ~120bhp/230ftlb
Step 5 –
We are starting to run out of big wins in terms of performance. The 2 things that we’ve not yet done are the air filter and the exhaust. In my opinion the exhaust is more important than the air filter, but many people will already have fitted a cone air filter by now. Most people will plumb for green cotton cone filter such as the K4.80
Then we need to look at the backbox. There is only one silencer in the exhaust so a performance backbox can help release the final few ponies. Custom jobbies aren’t going to be cheap,
Budget – £100-200
Power achievable ~130bhp/230ftlb
This is about the limit of “cheap” tuning for the non intercooled models. If you are after more power than this then you’ll need a bigger turbo