Am trying to see what would be best.. Turbo=bw s300 t4 twin scroll .91a/r And 3" downpipe.
Should I get a tail 60mm wastegate or a manifold with twin set up for tail 38mm or 44mm wastegate

 

Higer boost= Less wastegate
Lower boost= More wastegate

 

It really depends on several factors. Manifold design ,porting, exhaust housing size, recirc/dumped. Also, the lowest boost you will want to run can determine what suits your needs. I have an old school 46mm Tial with a 10psi spring and a cheap undivided eBay manifold. It holds 10psi to 5000rpm and creeps to 12 by 7500. Not great, but I can live with it for what it cost me.

 

Thanks for the replys guys. I just don't want to have boost creep but am guessing that's going to happen no matter want!!
I got lots to think about... Is anybody running a 60mm tail on here?

 

Can't go wrong with either. Neither set up is going to creep and both will hold a very low boost setting as long as the manifold design is good. Single 60 for simplicity if you can find one but a new design Turblown twin gate manifold will give you the best possible response.

 

WG piston area:

one 60 mm 4.38 sq inches

one 44 is 2.35 (note, the 60 provides 86% more area than a 44)

two 44s 4.71 ( only 7.5% more area than one 60)

two 38s 3.51

howard

 

I run a JGS 50mm race gate and have no creep..

 

Ok thanks guys!!!

 

Wastegate position on the manifold is more important than the size. I have seen Tial 60mm wasetgates creep on high flowing setups with poor wastegate placement.

Keep in mind that as load goes up it can become even harder to control boost without proper waste gate size, placement or a combination of both.

I tuned two cars last week on HKS cast manifolds that help boost fine around 11 psi, but as soon it was was cranked up they would overboost badly in the midrange.

 

Ok thanks for the info Eliot..
I'll be ordering that turbo this week.. 😁

 

Agreed. Wastegate placement is the biggest factor. I've had dual 38s creep as well as dual 44s, single 44's and single 60s on poorly designed manifolds. It really comes down to the manifold design. The cast HKS manifolds are pretty poorly designed in my opinion. That is why they came with the cheaper and smaller turbos (t04e, to4s, td06) The larger turbo kits like the t04R came with tubular manifolds. With dual 38s you should not have any creep if the manifold is designed properly. That being said, I recommend dual 38s on most of my kits.

 

IRPerformance am almost ready to buy the manifold and down pipe should be after Christmas 😁