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Jaiiiwon
29-07-2011, 10:01 AM
Hey guys just a simple question..

the low end torque of a boosted motor is primarily on how quick it spools?
in saying that, does that mean before it spools, the car is going to run like an NA motor or no?

now i know there are different types of exhaust manifolds for a turbo setup, but do they have similar characteristics as the NA types, for e.g. 4-1, 4-2-1, tri-y ?


Im just wondering. Just a little food for thought.

DLO01
29-07-2011, 12:36 PM
Yes, off boost, the motor will perform like an NA motor before the turbo kicks in. And of course torque and power will change when the turbo kicks in. Different style manifolds perform differently in a turbo setup. A short stubby un-equal length log manifold will perform different to ramhorn and different to a long length top mount manifold, they change turbo spool up time and performance.

Jaiiiwon
29-07-2011, 02:06 PM
also, do you know in-particular how each manifold performs individually?

for e.g. assuming the ramhorn would take longer to spool due to the longer path the gas would have to travel.. and the log would spool a lot quick.

is my assumation correct?

justinagar
20-09-2011, 03:23 PM
Yes, off boost, the motor will perform like an NA motor before the turbo kicks in. And of course torque and power will change when the turbo kicks in. Different style manifolds perform differently in a turbo setup. A short stubby un-equal length log manifold will perform different to ramhorn and different to a long length top mount manifold, they change turbo spool up time and performance.

Correct :)

Limbo
24-09-2011, 01:13 AM
to an extent, the difference is that with longer runners it will be more like an NA, shorter runners will make it alittle sluggish, but boost up faster, transition to boost is also more aggressive with shorter, but tapers off abit.

If you run small boost - shorter runners
Bigger boost apps generally you want longer runners