<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rorik &raquo;</TD></TR><TR><TD CLASS="quote">I just realized something, if I build a split housing manifold, won't the internal wastegate only vent 2 cylinders? That would be retarded...

I wonder if it would be worth it to get a non wastegated housing and use 2 wastegates to vent each side separately..</TD></TR></TABLE>

how much does the stock wastegate hold? i heard u have to run external cuz these turbos produce a lot of boost stock

 

do you guys think a holset h1c would fit on an ep3 or dc5? or maybe a k swapped eg or 88-91 crx? just curious for if i ever wanted to get another car.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wantboost &raquo;</TD></TR><TR><TD CLASS="quote">
have two runners going to the wg, one from either side of the collector</TD></TR></TABLE>

Thats the way to do it, if you only vent one 'half' you'll probably creep even on a big wastegate.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kasso &raquo;</TD></TR><TR><TD CLASS="quote">do you guys think a holset h1c would fit on an ep3 or dc5? or maybe a k swapped eg or 88-91 crx? just curious for if i ever wanted to get another car.</TD></TR></TABLE>

im not sure, if the manifold were designed properly im pretty sure it could clear the firewall. it should fit in the rex

 

cool. i dont think its gonna go in the teg. im gonna just do ls-t on the teg. and ill prolly put the built motor with holset in a rex

 

if you only vent 2 cylinders, then those 2 cylinders will have a lower back pressure when the gate is open, and a different afr..f that...and using 1 wastegate that vents both sides of the housing defeats the purpose of having a split housing, by letting the pressure bleed back and forth between the 2 housings!

By the way, the firing order for the b series is 1-3-4-2, right? So the paired cylinders would be 4-1 and 3-2, to get alternating pulses to each side of the housing. The best possible setup would then be 2 external gates, one on each side, as close as possible to the collectors.

have any of you guys seen anything built like this??

 

I remember seeing a pic of a split housing manifold somewhere on this site, but now I can't find it! damn it..

 

I think if you made the wastegate pipes a little on the long side and kept them divided as close to the wastegate itself as possible it won't be an issue. Flow takes the path of least resistance, make it harder to go up there, and it won't want to.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Paul_VR6 &raquo;</TD></TR><TR><TD CLASS="quote">I think if you made the wastegate pipes a little on the long side and kept them divided as close to the wastegate itself as possible it won't be an issue. Flow takes the path of least resistance, make it harder to go up there, and it won't want to.</TD></TR></TABLE>

defeat the purpose of a wastegate what?

 

Not harder to run to the gate itself, but harder for it to run all the way to the gate, make a 180deg turn and back down the other wastegate tube back into the other half of the collector. That make more sense?

 

What about that tube absorbing some of the energy of the exhaust pulse? (Like adding volume to the collector, except not directly in the main flow path) I don't know exactly how significant that would be, and I have seen setups like that, but I know if cost wasn't a factor, I would choose the 2 wastegates in a second. The whole point of the split housing is to minimize the energy loss to the turbine, and I'd like to stay true to that idea..

Another thing I've been wondering about, has anyone here used the bullseye housing? (T3 or dsm inlet) I know that's all the dsm people use, but no one knows the size or A/R of it..

 

well, the only problem with that is you have to use a dsm dp flange, and its somewhere between a .48 and .63, bullseye wont release the exact number. imo these housings are too small for the holset to truely shine. the one on my motor will be using a 22cm exhaust housing, or about 1.00ar give or take but remember i will be running very high boost levels (25-30psi)

 

an hx35 turbine wheel in a 22cm housing wont spool on a honda motor till at least 6-8k. Your running a 2.2 though arent you? You dont really apply

 

2.1, but ihave a fully built motor (block, head, etc) and everything is ceramic coated and it wont be an off the shelf holset, the wheels are gonna be played with a bit as well as the housing and im most likely going to try the hx40 wheel, not 100% sure yet

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wantboost &raquo;</TD></TR><TR><TD CLASS="quote">well, the only problem with that is you have to use a dsm dp flange, and its somewhere between a .48 and .63, bullseye wont release the exact number. imo these housings are too small for the holset to truely shine. the one on my motor will be using a 22cm exhaust housing, or about 1.00ar give or take but remember i will be running very high boost levels (25-30psi)</TD></TR></TABLE>

I heard the same thing about the bullseye housing, too small, but I'm wondering how it compares to the hybrid hx40 compresor with the hx35 turbine, in terms of backpressure, lag, etc.. So you're going to use the hx40 turbine wheel/housing? Do you know if there is such a thing as a standard size for the hx40 housing, or what the equivalent a/r would be for the 16cm^2 housing? I was thinking I might try a straight hx40 with the 16cm^2 housing, and try to build a split housing manifold for it..

I'm getting sick of this..the more I learn, the more questions I have..it never ends

 

It's all about manifold design... And wastegate placement. The smaller the A/R you use, the bigger the wastegate you need. Feed your wastegate not your turbo, or at least do a bounce-shot and you're good to go. Inspiration: F1 turbo days, CART, Hytech, RMF, Lovefab sidewinder, etc.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blundar &raquo;</TD></TR><TR><TD CLASS="quote">It's all about manifold design... And wastegate placement. The smaller the A/R you use, the bigger the wastegate you need. Feed your wastegate not your turbo, or at least do a bounce-shot and you're good to go. Inspiration: F1 turbo days, CART, Hytech, RMF, Lovefab sidewinder, etc.</TD></TR></TABLE>

I'm sure you know what you are talkin about, but could you explain why you need a larger wastegate with a smaller turbine a/r and vice versa?? I am still quite new to this and would like to understand why this is true. If you don't want to post in here could you pm me with the explanation if you have time? thankx.

 

Smaller turbine a/r the more shaft speed you get for a given exhaust flow. So, with boost control, boost onset is sooner due to more compressor/turbine revs per engine rev, so you have to bypass more exhaust volume to get to a particular turbo speed and boost level.

 

thanks blundar, but unfortunately we cannot all create our own manifolds; and unfortunately no one makes a log manifold that has a bounce shot off of the wastegate to the turbine inlet.

 

i'm pretty sure anthony at fab-works can cook something up. ive seen his ideas and they are absolutely crazy. he did my manifold and everything and i will be going back to him for one for my holset. tell him i sent you and he will treat you right

 

my h1c just came in today!!!!!!! this thing is huge!! people at my job thought it was a t67 or t70 or something. the turbine inlet looks really small. it looks smaller than a t3 inlet. it measures about 70mm by 108mm and its the split design. does that dimension sound like a t3 inlet or a t4 inlet? also, the outlet is 3 inch O.D. and like 2.5 inch I.D. v-band.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blundar &raquo;</TD></TR><TR><TD CLASS="quote">It's all about manifold design... And wastegate placement. The smaller the A/R you use, the bigger the wastegate you need. Feed your wastegate not your turbo, or at least do a bounce-shot and you're good to go. Inspiration: F1 turbo days, CART, Hytech, RMF, Lovefab sidewinder, etc.</TD></TR></TABLE>

i don't understand this. The lower your a/r, the higher your backpressure for a given amount of boost and airflow. Same mass of air, higher pressure=smaller opening to vent given % of that air..which is how you control the turbine speed..What am I missing? Or am I missing anything at all..?

p.s. I got a reply back from bullseye power, and the a/r of the hx40 mitsubishi bullseye housing is .55, and the T3 is .63. He said that a customer just put down 558whp on a 1.8 honda, I assume on the t3 style inlet housing. I didn't see the dyno graph though. I still think .63 is a little small.

 

558whp at what boost levels...more than likely 25+psi...and forget the bullsye housing you can make as much use out of a holset stock housing as theirs...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Paul_VR6 &raquo;</TD></TR><TR><TD CLASS="quote">Smaller turbine a/r the more shaft speed you get for a given exhaust flow. So, with boost control, boost onset is sooner due to more compressor/turbine revs per engine rev, so you have to bypass more exhaust volume to get to a particular turbo speed and boost level.</TD></TR></TABLE>

^^^ Thanks Paul, makes sense.

Does anyone know what efficiency island the comp maps linked to earlier represent?? Just curious.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rorik &raquo;</TD></TR><TR><TD CLASS="quote">

i don't understand this. The lower your a/r, the higher your backpressure for a given amount of boost and airflow. Same mass of air, higher pressure=smaller opening to vent given % of that air..which is how you control the turbine speed..What am I missing? Or am I missing anything at all..?

p.s. I got a reply back from bullseye power, and the a/r of the hx40 mitsubishi bullseye housing is .55, and the T3 is .63. He said that a customer just put down 558whp on a 1.8 honda, I assume on the t3 style inlet housing. I didn't see the dyno graph though. I still think .63 is a little small.</TD></TR></TABLE>

Someone did 558whp on the HX40/bullseye? I have been looking at those bullseye housings for a long time, but I am hestitant to go to a smaller turbine. I am torn between swapping my hx35 exhaust side for either the bullseye or an hy35. Any more info of the bullseye housings? this is the first time I have seen an A/R listed for his housings.