Stock 4efte exhaust manifold and turbo questions

[alanjg]

what modifications can be made to the exhaust manifold to perform better?

1. can it be ported? should the "+" dividing the runners be removed? what else can i do to it?


2. which turbo bolts on straight to the 4efte's exhaust manifold?... ct9 duh but i want an upgrade ...ct20 from hilux? Matrix

or could i just add an extension like a T fitting to the exhaust manifold to use a different turbo like a td04l and be able to use an external wastegate?

 

[alanjg]

something like this.... and in the middle of that extension we open a port for the external wastegate...

what do you guys think?

 

[Guye]

1. can it be ported? should the "+" dividing the runners be removed? what else can i do to it?

Porting the stock manifold to lessen the restrictions in the #2 and #3 runners has been done with success by other members before. The devision for the runners serves a purpose. This allows the pulse energy of the exhaust from each cylinder to be directed/used for spooling the turbo optimally. To put it simply, removing this will allow exhaust gases (energy) to potentially travel back into a runner not on exhaust stroke instead of spooling the turbine.

2. which turbo bolts on straight to the 4efte's exhaust manifold?... ct9 duh but i want an upgrade ...ct20 from hilux? Matrix

The best upgrade to bolt directly onto a stock manifold will be a hybrid ct9. Keep in mind that adding a more efficiently flowing turbo without addressing the manifold restrictions can potentially lead to piston damage.

or could i just add an extension like a T fitting to the exhaust manifold to use a different turbo like a td04l and be able to use an external wastegate?

There is a flange you can get that would allow you to fit a TD04 onto a manifold meant for a CT9. If you are going as far as to add a fitting for an external waste gate, you may as well just buy a manifold to suit your needs.

 

[alanjg]

1. can it be ported? should the "+" dividing the runners be removed? what else can i do to it?

Porting the stock manifold to lessen the restrictions in the #2 and #3 runners has been done with success by other members before. The devision for the runners serves a purpose. This allows the pulse energy of the exhaust from each cylinder to be directed/used for spooling the turbo optimally. To put it simply, removing this will allow exhaust gases (energy) to potentially travel back into a runner not on exhaust stroke instead of spooling the turbine.

but aftermarket manifolds don't have that division. why?

 

[Sigma]

They all do, Alan.

It's where the four runners collect.

 

[Guye]

but aftermarket manifolds don't have that division. why?

Most aftermarket manifolds are designed not only to flow efficiently (pipe diameter, runner lenght etc.) but also to best utilize the engine's firing order and exhaust pulse energy to aid in spoolup. The cheap stock cast iron manifold with it's restrictions is good/strong enough for what toyota intended for the car, but it's far from ideal. It needs the " +" bit.

 

[alanjg]

ok how about ebay manifolds, are they ok?


or the 5e n/a manifold cut and weld a flange? I'm confused with this because a lot of people says this works wonders, and a lot of ppl says that this material cant be welded.