So that's how they kept the boost under ~8-9 psi, huh

Chris

 

I don't know for sure, I'm only guessing. What concerned me about cutting the divider was that the exhaust would expand as soon as it got out of the manifold and into the cut-out area, then have to be compressed down again into the two separate scrolls. I thought that would lead to a lot of turbulence and hence restriction. I don't know for sure that the hole is less disruptive to flow, it's just a theory. The area near the hole will be subject to a lot of turbulence when the wastgate is open (due to lower pressure in the rear scroll and flow through the hole), but I think that as long as the pressure in the two scrolls is equal the flow will be pretty smooth through that area.

 

yup! if it wasn't so small, I'd experament w/ running one on a 5.9... I thought about using one as a top for a set of towing twins instead of an HY35...

they're small, but the map is still good on them up in the 35+ psi range... I'm putting one on a ford 2.3 turbo engine... lots of guys are running the HY35, but they're having boost creep issues because of the small wastegate orifice.

Forrest

 

WD, i noticed in your sig that you have lowered your boost to 30 psi. if i remember correctly, it was at 35. any particular reason?

 

Yep, trying to get the turbo back on the map on advice from Bushy. Doesn't seem to run any hotter (or cooler ) there. Since I already have a backpressure problem it doesn't make much sense to cram more air in if it doesn't drop the EGT. I'll play with it more after I get the water/meth injection installed and see where it likes to run. It's killing me to have the setup sitting on the bench and not be able to put it on the truck. Dang rain!

 

I agree that I would not try to push an H1C much past 30psi. You might find it much harder to keep at 30psi with water/meth.

 

yeah, I've done the same thing w/ my HX40... EGT's seem to stay the same wether I've got 35psi or 45psi on the gauge... and all points inbetween... I shoot for 38-40, but sometimes this POS boost elbow shows me only 35

anyhow, sometimes less is more... same EGT's, less worry about the head gasket.

Forrest

 

Dragging this one back up.

Any new reports or thoughts to post?

 

Right now I'm running a stock wastegate actuator and it can keep the boost at 25 psi. EGT is still toasty at high RPM. When the water/meth kicks in I can still get the boost up to 32-35 psi. It takes longer to get too hot with the water/meth on, but that's due to the cooling action of the water/meth, not the extra boost.

I think it's a good mod for anyone to make. I don't like the idea of the front 3 cylinders being more restricted than the back 3, especially since most of us read EGT out of the back half of the manifold.

 

What size of a drill bit would you need? Can a 3/4" bit suffice? Also how precise does the hole have to be? Reason I ask is because I don't have a drill press. I have access to one, but they're closed for the weekend. I might have access to another press more local, but I don't think it has anything on it for hold-downs.

Trever

 

3/4" would be fine. The idea is just to vent the front half of the housing into the rear half. I've heard Jannety does this on 12 and 14 cm housings with a 1/2" hole(I have no first hand knowledge of this).

No need for ultra precise work, I don't see any reason you couldn't clamp the housing in a vise and do it with a big hand drill. You wouldn't even have to take the housing off the turbo if you came in from the side so all the chips would fall out of the housing flange. Looking for an afternoon project, eh?

 

Dragging this thread back up.

It looks like one of my next projects. I wnt to go as far as I can on the stock turbo in my truck. My truck is supposed to have a banks kit on it, but the turbo looks stock???

What parts do I need for this project and where do I get them??
I was thinking I might need a new housing gasket?? Is that it other than machining the housing?

thanks alot

 

This modification has been around almost as long as Piers has.

 

Andy,

Is your HTB2 not dual port w/g'ed??

I thought they were.

 

HTB2 is Duel Port Gate