2.75 exhaust v standard 2.5

[220bhp]

I have a standard 2.5 exhaust on my 3b coupe with no cats, running rs2 exhaust manifold plus turbo and injectors,with standard air box and inter cooler ,what if any advantage is there in fitting SS 2.75 turbo back system including sports cat before I get it remapped.

[HMS-S6]

did you sort the turbo problem out then pal?

[220bhp]

Hi mate turbo has been rebuilt and is back on the car.
I see you are still having problems with your S6. This is a long shot but has the cam belt been replaced in the last year or two, if it has then there is a chance that it was not torqued up sufficiently allowing the key way to move.
Motronic learns behavior and compensates, this will not be overcome by resetting the ecu and as far as I know it dos not throw any codes and the car will run like it has no turbo.If the keyway gives up you kill the engine but i sometimes moves just enough to cause a problem such as yours.
As I said it is a long shot but I know this can happen because when I first got my 3b and changed the cam belt the keyway was hanging on by a thread, and at the time it ran like crap.

[HMS-S6]

Hi mate turbo has been rebuilt and is back on the car.
I see you are still having problems with your S6. This is a long shot but has the cam belt been replaced in the last year or two, if it has then there is a chance that it was not torqued up sufficiently allowing the key way to move.
Motronic learns behavior and compensates, this will not be overcome by resetting the ecu and as far as I know it dos not throw any codes and the car will run like it has no turbo.If the keyway gives up you kill the engine but i sometimes moves just enough to cause a problem such as yours.
As I said it is a long shot but I know this can happen because when I first got my 3b and changed the cam belt the keyway was hanging on by a thread, and at the time it ran like crap.

Thanks but no, i checked the valve timing via the mark on the flywheel and all was ok!

It has been determined that its running dangerously (to pistons) lean!! Just tring to find why. Having changed MAF sensor, Lambda sensor, TPS, ECTS and injectors i'm looking towards fuel pump!

[HMS-S6]

Anywho, back to your car. Why not go 3" turbo back incase you fancy going more BHP later on?

[220bhp]

How can you check the timing is right if the crank pulley is of a few degrees, think about it,

[Jamo]

I have a standard 2.5 exhaust on my 3b coupe with no cats, running rs2 exhaust manifold plus turbo and injectors,with standard air box and inter cooler ,what if any advantage is there in fitting SS 2.75 turbo back system including sports cat before I get it remapped.

Less lag, lower egt and back pressure, better for the engine.

You'll be o.k replacing it without remapping.

[Acidburn]

Well worth doing, you will find the engine will rev easier. I'll let you know about that pump, the place was shut when I got there today
sorted the boost out temp on the car, needs winding up more.

[HMS-S6]

How can you check the timing is right if the crank pulley is of a few degrees, think about it,

Because regardless of the pully position, the flywheel mark can't move and with that lined up the cam pully is spot on.

Also don't forget that this problem STARTED out intermittant and only in the last few weeks has become permenant