Help me redesign my WG runners
03-14-04, 08:58 AM
#154
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It's not ******* it up, it's a proven method. From the looks of pictures I've seen it done to they have been undivived housings though. So I'm wondering if it can be done with my semi-divided housing. There is no other way I can do this. I don't have the room to run runners out of the manifold elsewhere, even if I used two smaller gates.
03-14-04, 11:49 AM
#156
Originally posted by Directfreak
You're gonna **** up your exhaust housing to control creep, instead of reworking the WG and WG runners?
You're gonna **** up your exhaust housing to control creep, instead of reworking the WG and WG runners?
He has done his research and he is right that it should work fine.
The only thing is that, look how many manifold designs don’t have the creep that he is experiencing, he should be able to find a design that doesn’t require him to weld a WG passage on his turbo I would think.
But he is getting his project moving, and making decisions to correct problems, and it looks like he is doing a pretty good job from here.
It is very difficult to create things from scratch and make decisions based on what you have learned and acquired from all that’s happening to a system, and trying to make the best decision that will require only one go at it to fix a problem, when you don’t have the time/will to do it again.
03-14-04, 01:22 PM
#157
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enzo- If I were to form the piece of pipe and cut the hole in the housing could I send it to you to weld it for a charge? I don't feel confident myself welding it as I've never welded cast and I don't want to learn on my housing. It seems you've had experience welding 304L to cast.
rotarypower- You're 100% correct
There should be a way for my old wastegate runners to work BUT I do have a lot of things that are working against me.
First is how I made the flange to match up to the stock cosmo exhaust sleeve and the smallish 1.68 ID main runners. With the combo of those two I get very small amount of turbulance and high velocity passing by where the old WG runners tapped from the mains. Someone said once that the gasses may be flying right by the holes that fed the WG and right out the turbine.
Second is how unrestrictive my exhaust is after the turbo. I have a fully 3" mandrel bent exhaust, turbo to exhaust tip. I have only one 3" straight through muffler at the rear. It may be easier for the exhaust gases to go out the turbine than it is to run though the old wastegate plumbing causing my high rpm boost creep.
Third is I don't have the room to run WG runners out of the main runners anywhere because of how I chose to design my manifold. If I were to turn the flow right out of the exhaust port like most of the tubeular manifolds I would have no problem at all finding a place to weld in WG runners. I wanted to get that section of straight out the rotor housing though.
To me routing the exhaust out the turbine housing would be ideal because it's at the point of restriction and the wastegate will have a nice Y into the exhaust flow. I just need to know if it's the way to go with my semi-divided Mitsu housing.
rotarypower- You're 100% correct
There should be a way for my old wastegate runners to work BUT I do have a lot of things that are working against me. First is how I made the flange to match up to the stock cosmo exhaust sleeve and the smallish 1.68 ID main runners. With the combo of those two I get very small amount of turbulance and high velocity passing by where the old WG runners tapped from the mains. Someone said once that the gasses may be flying right by the holes that fed the WG and right out the turbine.
Second is how unrestrictive my exhaust is after the turbo. I have a fully 3" mandrel bent exhaust, turbo to exhaust tip. I have only one 3" straight through muffler at the rear. It may be easier for the exhaust gases to go out the turbine than it is to run though the old wastegate plumbing causing my high rpm boost creep.
Third is I don't have the room to run WG runners out of the main runners anywhere because of how I chose to design my manifold. If I were to turn the flow right out of the exhaust port like most of the tubeular manifolds I would have no problem at all finding a place to weld in WG runners. I wanted to get that section of straight out the rotor housing though.
To me routing the exhaust out the turbine housing would be ideal because it's at the point of restriction and the wastegate will have a nice Y into the exhaust flow. I just need to know if it's the way to go with my semi-divided Mitsu housing.
03-16-04, 08:49 PM
#159
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Ok, just spent tonight forming that piece of pipe to the turbine housing. A bit more grinding and I'll be ready to cut the hole in the turbine housing.... it's going to be hard making that first hole in it 
I pieced it all together and it looks bad *** 
I'll have to take more pic's when it's all formed together.
I pieced it all together and it looks bad *** I'll have to take more pic's when it's all formed together.
cast iron is fun to cut
me
03-18-04, 06:40 PM
#162
Hey Cam, I just came back and re-read my post. I apologize if it came across like an @$$hole. You know I dont come across that way.
On a side note, In my opinion only
I would rather make a whole new exhaust manifold, from scratch - than go through the Turbo exhaust side.
On a side note, In my opinion only
I would rather make a whole new exhaust manifold, from scratch - than go through the Turbo exhaust side.
03-18-04, 08:12 PM
#163
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No problem Alex, no offence taken.
Well either way the damage is done now. The turbine housing and piece of pipe are on their way to Enzo's house.
If you think about it, coming off the turbine housing is the ideal place. Ideal for a undivided, ideal for a divided..? I guess I'll find out.
Well either way the damage is done now.
The turbine housing and piece of pipe are on their way to Enzo's house.If you think about it, coming off the turbine housing is the ideal place. Ideal for a undivided, ideal for a divided..? I guess I'll find out.
03-20-04, 09:42 AM
#164
See that was my only concern was the breakup associated with having a extra path in the housing itself, arguably one of the most important place to have smooth transition, that would cause eddies and discontinuity in the flow.
One great benefit to its location though is its tendency to flow out your WG port very easily because of its location and orientation in regards to the flow path.
That is one things I had kinda wondered if that was one of your problems all along, was in addition to the tubing carrying the flow faster than normal, that the old WG ports were not being able to be utilized because of such perpendicular positioning to you main flow path.
Anyway cant wait to see some pics!
Enzo you’re a good man, that was really cool to do that
One great benefit to its location though is its tendency to flow out your WG port very easily because of its location and orientation in regards to the flow path.
That is one things I had kinda wondered if that was one of your problems all along, was in addition to the tubing carrying the flow faster than normal, that the old WG ports were not being able to be utilized because of such perpendicular positioning to you main flow path.
Anyway cant wait to see some pics!
Enzo you’re a good man, that was really cool to do that
03-20-04, 10:25 AM
#165
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I guess time will tell if it will work or not. I did get more aggressive at cutting the hole in the housing than I originally intended to though. I hope that doesn't cause any turbulence like you said. For you that have the Maximum Boost book turn to page 125, that is what I was going for.
That's why I put it there, great tendency to flow right out the WG
When I did my first WG runners I tried to lay them down as much as I could to "Y" them in but in the end I think it was a combo of too early in the manifold, small main runners, too many bends in the WG plumbing and unrestricted exhaust after the turbo.
I'll take pic's when I get it back and the finish port work is done
I coulden't agree more! Enzo is the man!
That's why I put it there, great tendency to flow right out the WG
When I did my first WG runners I tried to lay them down as much as I could to "Y" them in but in the end I think it was a combo of too early in the manifold, small main runners, too many bends in the WG plumbing and unrestricted exhaust after the turbo.
I'll take pic's when I get it back and the finish port work is done
I coulden't agree more! Enzo is the man!
06-17-04, 07:23 PM
#175
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Yup https://www.rx7club.com/showthread.p...ighlight=creep
It doesn't go over 9psi now Thanks for telling me to go this route!! Where have you been? Is your damn car back together yet?
https://www.rx7club.com/showthread.p...ighlight=creepIt doesn't go over 9psi now
Thanks for telling me to go this route!! Where have you been? Is your damn car back together yet?