Was having a read through Howard's turbo/dyno thread where recently there was some manifold discussion. Rather than muddy the waters there I thought I would start a separate thread.

Am building a setup focused on response and torque as opposed to big hp (looking for circa 400hp) and it seems the divided T4 hot side is the way forward to achieve this goal. Was originally thinking the dual waste gate path was the go, and then spotted Howards manifold design. That got me thinking...... Reliability is also a key factor for me so wondered whether a 2 into 1 design with a large single gate could be the answer as opposed to the slightly more complex dual gate with the extra joints etc that could provide increased risk of failure.

Read the feedback from another forum user who cited structural issues with a similar design they had done, but I guess my question is would a full divided setup with the two waste gate pipes merging into one then fitting one gate and then plumbing back to the dump pipe have any merit?

And while I am on it is there a known pipe dia. For the exhaust mani that provides get the gas velocities right for maximum response without added restriction?

Thanks in advance fr any input.