Turbo Manifold Options

[scotty nm35]

That's mental response for a GTX35..

I think the stock manifold is partially the reason the response is so good.

[AngryRB]

Can anyone confirm wether the length of the runners creates lag? If long runners are best on the intake manifold for response/bottem end torque, then is it best to have the exhaust runners short to keep the flow as close to the turbine as possible, hence stock manifold being best for street?

[GTSBoy]

It's more complicated than that. Inlet manifold runner lengths are about pulse tuning which means the rpm at which the pulses add up to give you a little boost of flow into the cynlinder. NA exhaust manifolds also benefit from pulse tuning. Turbo exhaust manifolds, whilst they CAN benefit from pulse tuning, generally want to be MUCH shorter than the lengths needed to obtain suitable pulse tuning. Turbo manifolds are really just a means to get the exhaust gas to the turbine as elegantly as possible. And given that turbines work from a pressure differential across them, you don't want the total volume of the turbo manifolds to be so large that it takes time to build pressure in it - which would equal less response, even if it were only a few milliseconds.

[AngryRB]

after having and comparing the 6boost to the stock, i would say theres possibly 50% or greater volume inside and the collector is notably smaller on stock manifold, might be some better heat retention in the stocky too being smaller and tight.. Nissan must of thought it was a decent design, seem to have build everything else to exceed its factory output.

[B-rice]

How can it be off topic, people need to realise the stock manifold isn't the restriction it's made out to be. I must admit I was surprised with this result.

I did the recent fab work on it, the car is still restricted by a hollow 3 inch cat in the 3.5 inch exhaust, return flow cooler, and the Z32 afm still holding back the 4 inch intake. There would be much more in it if the gearbox could take it... Not too laggy either imo.

i wasnt saying your off topic unless if you mean the other guy. Its quite an amazing result what im worried about however running a stock manifold. How will the engine bay temperatures be like.

[rondofj]

Damn that setups exactly like how my PT5558 is mounted onto my stock mani, gate off housing n all

[Lithium]

So far the only cars I have heard of making that kind of power on the stock side mount manifold have run nitrous oxide to do it - RIPS in NZ did a couple in his early days. I wouldn't be too surprised if you could squeeze an E85 setup up to that power level, but if it were possible it would not be that nice on things (E85 is quite good at covering up a not-flash-setup) and I'd say would make no way near as much on pump gas.

[R32N00B]

after having and comparing the 6boost to the stock, i would say theres possibly 50% or greater volume inside and the collector is notably smaller on stock manifold, might be some better heat retention in the stocky too being smaller and tight.. Nissan must of thought it was a decent design, seem to have build everything else to exceed its factory output.

yes thats just it. Smaller diameter = Velocity (spool/torque) whereas larger diameter = Volume (HP up top)

same idea as intake manifold runners

Im switching from a custom 1 1/4in steampipe log manifold to this twin scroll 1 1/2in, I will have back to back data between the 2 soon enough, relative to spool/lag time, and HP/TQ numbers overlaid on a dyno graph. sucky part is i never got past 15psi on the log mani (ran out of fuel) so I will do back to back at 15psi (my turbo is way below its efficiency at 15psi)

Im very curious myself

Edited September 25, 2013 by R32N00B