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Hi folks,

If I change my aging Garrett BB T28 to something that has less lag and is newer and probably more efficient.. do I have to remap my ECU ?

ECU works on MAP sensor.. so I'm thinking it doesn't matter what turbo I use.. the air pressure is the same..

The boost curves are different but the fuel and timing maps should be the same since I'm not changing injectors, boost or air intake/manifold.

Cheers,

AW

I'm going to jump in here, feet first, without checking for hidden objects under the surface...and say yes, you should have your ECU remapped. Reason being, less/no lag means the boost will be available at lower revs, which means you need more fuel earlier. There could be other reasons as well...or I could be totally wrong....which I'm sure will be pointed out by more savvy members of this forum.

J

I'd confer with Juffa here - I know my (EManage) tuning map is based on boost, with various increment points based on rpm.

Can't hurt to be safe.

You could get away with it for general driving around under little to no power, but under boost you'll probably need to add fuel. A larger, or more efficient turbo will usually result in cooler air charge into the engine, the cooler (more dense) air needs more fuel to mix with it (basic of more air more fuel). The difference will probably be quite minimal, but it is generally enough that without making the changes you might see some fairly lean AFRs with the newer more efficient turbo.

I've run a bunch of different turbo setups on the same engine and always got a retune with each turbo.

There are a few benefits to a retune as well, the cooler intake air might allow you to slide a few degrees of timing back in under boost too, which should equal a bit more power, espescially at lower boost levels. Depending on what you want to do with the car, you may also be able to pull some timing to increase exhaust temp to spool up the turbo quicker (at the cost of fuel economy and potentially turbo life).

In short, there will be a few minor changes required, but not a full retune, a good tuner should have it knocked over in almsot no time as they wont need to adjust the hard stuff like cold start and idle.

Hi Andrew,
Not sure how I missed this thread. You will need to get the Autronics tuned mate.
Check your PM for Steve's contact number.

A more efficient turbo will require a different fuel map.
Have you got adjustable cam gears?

Regards,
Les

I can see you're going to try and show me some new shiny stuff Les..

It might work..

He needs to show you some of these ..



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