I am keen to fit a full exhaust to mine before tune time as from what I have seen and been told there is a benefit in having the ability to make a lot more torque. This will require for me to pull the GT3576r and get a port, flapper and actuator done. While the turbo is off I would be happy to do the wheel upgrade for a bit more top end.

I have a GT3566r (machined 0.5 cover), ETM modified rear and 38mm Tial gate sitting at home......if its cost effective to put a modern billet wheel on that ill give it to ya cheap cheap as its just sitting around doing nothing. You would have the screamer to deal with though and plumbing that back would add to the cost though :-(

IH8TOADS

Here's an example of what I understand to be an initial first run E85 tune (which appears to have previously been a 98 tune) which shows more boost early does not equal more torque early. In this case the boost on ramp up was slower with E85 and yet torque was higher/or no worse coming onto boost. Possibly due to more timing and earlier due to the use of E85 as indicated in my earlier post. Hence why IMO I would step up to a bigger turbo when using E85.

this is from 2 different cars

Were they both on E85?

The green line is Jets car from SA, he is running 60lb injectors so is using 50% 98ron and 50% United E85

They are also different turbos

Who Sells GTX3876R Turbos for the FG? and is there ones that will bolt onto the factory manifold and re-use all the original fittings?

I'm looking at gtx3576 for mine as I only want 350rwkw and to keep as much response as possible due to having a manual,

From what I can see to make then fit you just put the core back into your original turbine housing and all the lines bolt back up, but you will need to modify the intake pipe and the outlet pipe where they connect to the turbo (someone please correct me if I'm wrong)

Try GCG turbos online shop.

I'm looking at gtx3576 for mine as I only want 350rwkw and to keep as much response as possible due to having a manual,

From what I can see to make then fit you just put the core back into your original turbine housing and all the lines bolt back up, but you will need to modify the intake pipe and the outlet pipe where they connect to the turbo (someone please correct me if I'm wrong)

I. think the stock housing also needs to be machined a bit to fit the larger compressor wheel of the GTX

Just my two cents worth. I was considering the gtx3576 and the gtx3582. I ended up getting the gtx3582 and I am very happy with how responsive it is. I drive a manual fg xr6 turbo and there is no discernible difference between the gt3576 and the gtx3582 in lag. And it pulls like a train. I am making 345 rear wheel kilowatts at 3400 rpm.