SOLVED!!

Hello guys.. its been a while..

Been building a track Honda for a few years now ( time attack not drag)

Need some help with a choice i've got to make..please please


After a few laps this summer my small turbo seized up and upgraded to a bigger turbo.

Now i'm having problems with boost creep.

Its not rocket seience and I know the basics but I am still a noob.

Basicly my wastegate is too small in the position it is in.


Info:

Goal:
Drivable FWD track car with gear controlled boost, 400whp in low gears and around 550 in high gears , this is why boost control is important.

Turbo:
BW S300 s362

Turbine: T4 .88AR single scroll 3"Vband outlet
Compressor: 63mm inducer and 88mm exducer 4"inlet and 2,5"outlet.

Wastegate at the moment a single Tial MV-R44 placed under almost 90degr of the manifold.

The 2.2l 4 cylinder is fully build and flowed and it moves lots of air.
full 3"exhaust, 2,5"charge piping.

On the dyno it started to creep as soon as the turbo started spooling. at first we tought the wastegate was broken or the boost solenoid was messing things up.
we went sping pressure only (.07bar or 10psi) but it did the same. boost was uncontrollable from about 5200 rpm.

Checked the wastegate and its fine.
After some research I reached the conclusion the angle and wastegate size together with a high flowing/low backpressure turbine its not gonna hold the low boost.

I know now about the idial way with the Y way of fitting the wastegate.



I have thought about it long and hard and came to a few options.
Can I please have your thoughts on the following:


Options 1:

change the 44 for a 60mm wastegate on the existing sopt and file the angle to smoothen the flow a little.





Option 2:

fit another 44 wastegate on the front of the manifold
This is not a good spot as i rather have it on the oposite side but there is simply no room (unless I make a sharp bend to the front)



Option 3

Fit a 60mm wastegate on the turbine housing.
I have read alot about this and there are pros and cons. but I am confident I can fit this correctly. just a little worried about the turbine characteristics.





I hope someone can help me out a little..
Thank you in advance!

 

As an H turbo nut... I have always like the Wastegate out the front. But should work okay on the side. Main thing would be the surface area is equal all around. If front is larger then you'd want it out the front. The manifold looks to be a good design, so I would rule that out. Since sometimes crappy flowing manifolds will result in boost creep.

The main things I see...

Turbo choice... a larger turbo efficiency range wont be till higher boost levels. So can effect boost steadiness down low...

I think in theory smaller Wastegate will be better on controlling boost down low. Your 44 should be good all the way upwards of 600 hp.

I would probably take it apart and replace it with new springs see what happens...

Then maybe if that doesn't work... start with the more intense stuff like mounting the Wastegate out of the front. If you have to go this way out the Front make the outlet have a slight nose cut/bend/oval then extend out like a neukin manifold. Believe that is one of the best ways on flow.

I would not run the wastegate into the housing. Think your asking for more trouble far as flow.

 

Test the waste gate for leaks first before anything

To me

That big t4 housing is just a nice big exit for the exhaust

If this were me id make a new manifold to give the waste gate priority over the turbo

 

A 750+ capabale turbo in a T4 housing with a .88AR on a time attack car??? That turbo is going to be like an on off switch and hard to regulate at your power goals. With that big of a turbo and a .88AR by the time you start making boost you are moving a lot of air.

 

You sure it's not just the engine that has a lot of air in it?

 

OMG its solved...

holy crap...

guys, I must appologise for asking first before checking all possibilities..

When I took everything apart I looked into the wastegate pipe and saw this:





That explains everything!!!

I measured the piping and its 44 mm outside 40mm inside diameter so i'm changing it into a 48/44 pipe and install a new flex section.

Can't believe it.. sleepless nights, dynosession waisted and almost bought an expensive wastegate!

BTW it is a NEUKIN manifold. don't know why he put the wastegate on the side as I did't ask for it but hope its works ok.

And I made a mistake, its the T3 .82 AR turbine housing ... Buet yeah, still a bit big for time attack

Thanks for looking and replies!

 

I hope you learned your lesson

Never put those kinds of flex sections on a turbo car

 

LMAO yea that would definetly restrict you with backpressure on WG. Get a quality flex pipe this time!!!

 

vibrant turboflex!

 

one of my friends had the flex section in his downpipe collapse like that. it was costing him tons of hp. be wary the flex joint for sure

 

I have been using them for years and I never had one failed.
I wonder what makes them fail like that?

 

thats pretty standard wg placement for that style manifold on an h22, and it works great.

 

Cheap flexes been known to take a crap... the heat distorts them and they eventually makes them very britle thus get the small sucked in look...

 

I think it pulled a vacuum when the wastegate was closed . Getting a flex with inner core this time!

Ill post the results as soon as its tuned.
Don't expect 700hp , its for time attack and its in europe