whats the differents between 38mm and 44mm tial wastegate.

i have ls/vtec darton sleeve 84mm cp piston, bisi rods, delta 272 cams, bisi valve train and turbonetics turbo.

 

44 is going to prevent more boost creep, if you have a ramhorn usually its good to run 44mm

 

That is dependant on the size of the turbo used as well as the boost pressure that you plan to utilize. anything that is lower pressue levels below 20psi for anything 58lbs/min or more would be best fitted with a 44mm. If just using your average 49-55lbs/min, and using under 20psi of pressure, the 38mm will do fine.

It depends upon what you have. List that, and everyone can be more precise in their answer.

 

The Turbo is a Turbonetics T3/T4B Hybrid Ceramic Ballbearing Turbo consisting of a T3 Stage III trim turbine section, and a T04B compressor section with .63 ratio. The T3/T4 HYBRID offers the low inertia and fast boost response of the light weight T3 turbine wheel and the high airflow characteristics of the T4 compressor family. The TURBONETICS CERAMIC BALL-BEARING T3/T4 HYBRID series.

 

Lol... You'll be fine with 38mm

 

based upon this information (though it does not give a compressor wheel measurement at all) it can only be inferred that the turbo flows less than 60lbs/min, in which case, assuming that the manifold has its wastegate placement in a proper location, a 38mm should do well enough.

 

heres my manifold

 

that's probably not going to control anything less than 1.5 bar unless your backpressure is through the roof

 

my turbo

 

so ill need a 44mm wastegate.

 

no, you need a manifold that gives some priority to the wastegate

 

do you have any pics on manifold that gives some pirority to the wastegate.

 

you're gonna have to get a 38mm with that manifold, or have the elbow cut off and a 44mm flange welded on.

 

it has a 38mm

 

this is pretty much perfect

 

Perfect, and perfectly horrible?

So is there anyway to reconcile the wastegate manufacturer's desire for complete wastegate priority with the engine builder's desire to have a design that provides optimum max power through total turbine priority? I've seen some designs that have a nice flow path to the turbine housing, and also have a nice shallow angle of divergence to the wastegate. Would that be a nice compromise?

 

As stated above, it really just depends on the turbo you plan on running and the boost you plan on running. But honestly the difference between the 38mm and the 44mm is not a lot. I like the 38 as it is easier to package in tight places and flows just fine.

 

And I thought with all of the manifolds you've seen you'd have a collection of pristine perfect manifolds to show off. That thing is ugry!