Single Turbo RX-7's Questions about all aspects of single turbo setups.

Help me redesign my WG runners

Thread Tools
 
Search this Thread
 
Old 12-02-03, 03:04 PM
  #26  
SCCA Rookie

 
Barwick's Avatar
 
Join Date: May 2001
Location: Sterling Heights, MI
Posts: 1,936
Likes: 0
Received 0 Likes on 0 Posts
I'm no mechanical engineer, but crap man, I think those wastegate runners are WAY too long. IMHO if the exhaust runners are that far apart and staying that far apart, then maybe run one wastegate for each.

But really what I'd do (by the way that manifold is freaking HUGE) is put the wastegate WAY closer to the main exhaust tubing. It's got an awfully long way to go before it even hits the wastegate, and I don't think it's too happy about that. I'd say split the wastegate tubes off the main runners when they start to get closer to eachother.
Old 12-02-03, 04:18 PM
  #27  
no

 
suganuma's Avatar
 
Join Date: Apr 2001
Location: Dallas, TX / Tokyo, Japan currently
Posts: 2,295
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by setzep
I'd love to get more ideas from anyone. If anyone wants to see a picture from a different angle or on the car just let me know.

Thanks guys
Cam
setzep, please do post some pictures of it on the car. Pics with the intake manifold and turbo on would work best to show how much room you really do have to work with.

I think most of Barwick's ideas make sense. I haven't heard from carx7 about him having boost creep problems and his WG placement is quite close to the runners. If you did shorten the runners that much, it seems like you'd have enough space to run smaller dual wastegates.

Personally, I think that you're hurting yourself by running a single wastegate after doing all of that work to get the main runners divided and tuned. Joining those tubes back together for the WG seems like a step backwards in the whole general idea behind your design.

I know you don't want to spend more money though. And I don't want to keep coming back to this if your mind is made up.

what size main and WG runners are you using anyways? They look the same size? 1.5" or 2" o.d.?

-Nic
Old 12-02-03, 05:02 PM
  #28  
Rotary Enthusiast

iTrader: (31)
 
carx7's Avatar
 
Join Date: Jan 2002
Location: Austin, Tx
Posts: 1,478
Likes: 0
Received 3 Likes on 2 Posts
Hmm, I think there is a solution, but as others said, I'll like to see a shot of the clearance between the snail and and mani? Any chance you can put the WG in that area vertically?

-C
Old 12-02-03, 06:07 PM
  #29  
IRS Champion

 
enzo250's Avatar
 
Join Date: Aug 2001
Location: NY
Posts: 2,038
Likes: 0
Received 1 Like on 1 Post
Here's a header i built a few years ago.

There's nothing wrong with using one wastegate when you have a divided header.



Old 12-02-03, 06:10 PM
  #30  
I'm your huckleberry..

 
Steel's Avatar
 
Join Date: Jul 2002
Location: Tucson, AZ
Posts: 736
Likes: 0
Received 0 Likes on 0 Posts
Carx7: that's a really nice header. It looks like the turbo would be sitting right underneath the hood with that... any chance that you would share that design? I'm not very well versed in CADD, but that is pretty much what I had in mind for my eventual TII
Old 12-02-03, 07:22 PM
  #31  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
Barwick- I think everything looks a lot bigger than it really is in the pic's. When I made the WG runners I was hoping they would work off of pressure instead of flow. I think my exhaust manifold pressure is too low to vent the exhaust in a effective manner. Or maybe my turbine housing is a bit too small. Hopefully the new pic's will show some more insight to what it really looks like and what room I have to work with.

suganuma- What I'd like to get it to look like is what enzo posted. See how the two tubes kind of Y into each other? I just have to find the room to do so I think. If it really came down to it I would run a dual WG setup but right now I'm considering that last unless someone wants to buy my 46mm tial. The main runners have a ID of 1.68" and the WG runners are like 1.3" ID.

carx7- see pic's

enzo- That manifold looks flat out bad ***! Congratulations!

again, if you guys need any other angles just let me know.

Thanks

Old 12-02-03, 07:29 PM
  #32  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
another pic

Old 12-02-03, 07:33 PM
  #33  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
another

Old 12-02-03, 08:20 PM
  #34  
Freedoms worth a buck o'5

 
Maxthe7man's Avatar
 
Join Date: May 2001
Location: Calgary Alberta Canada
Posts: 2,544
Likes: 0
Received 1 Like on 1 Post
It has to be something with the turbine sizing.... As Setzep said before, his is very similar to mine, although I only use a 40mm and have no boost creep whatsosever... Setzep do you still have pics of my manifold? Post them with yours, if it is manifold design, I would like to know why mine works and yours doesn't, I don't think it has anything to do with the manifold..Max
Old 12-02-03, 08:35 PM
  #35  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
If you posted that's what I figured you'd say Max. I'm just trying to get all the feedback/input I can. I'll look for a pic of your manifold.
Old 12-02-03, 08:43 PM
  #36  
Rotary Enthusiast

 
Crusader_9x's Avatar
 
Join Date: Sep 2001
Location: Woodstock, GA
Posts: 1,384
Received 0 Likes on 0 Posts
if u have room i would say make the runners going to the wastegate look like a y in between thetwo main runners on the underneath. that way there still pretty close to being equal length and the angle off of the main runner can be alot more like a 45 then a 90. but again just if u have the room that is what i would do
Old 12-02-03, 08:50 PM
  #37  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
Bing! Here is Max's that works.

Old 12-02-03, 08:56 PM
  #38  
no

 
suganuma's Avatar
 
Join Date: Apr 2001
Location: Dallas, TX / Tokyo, Japan currently
Posts: 2,295
Likes: 0
Received 0 Likes on 0 Posts
is it just me or do you have a TON of room to go in the DOWN direction?? Maybe I'm missing something in the pics? Is there a reason you're at the top of the manifold with the WG runners? If you want to bleed them together smoother (like I think you're saying with more of a Y than a T) then it seems like going to the bottom of the manifold gives you the most room to do that as you please...

what size is the turbine housing? .84?

My earlier comment comparing how you have it setup to an H-pipe was more in reference to how you're now balancing the flow between the runners instead of keeping seperate pulses. But, I think there is definitely something to how the rear rotor has a shorter path and hits a pretty sharp bend.

enzo - I agree that it will work fine to combine the tubes. I just don't think it will work as optimally as a fully divided setup would and it looks like he went through a lot of work to make a "divided" manifold and may not be getting the full fruits of his labor now.

Maxthe7man - I'd be really interested to see pictures of your manifold as well.
Old 12-02-03, 09:03 PM
  #39  
no

 
suganuma's Avatar
 
Join Date: Apr 2001
Location: Dallas, TX / Tokyo, Japan currently
Posts: 2,295
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by setzep
Bing! Here is Max's that works.


well....****...

I assume you've checked your plumbing to the wastegate and the wastegate itself for a leak??
When I first went single turbo, I had a problem with creep on an HKS standard and I thought it was the size of it, but when disassembling things, I found a leak in the line to the wastegate...man, did i feel stupid

I'm thinking....
Old 12-02-03, 09:09 PM
  #40  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
I can't go underneath because the steering arm would hit anything under the main runners.
Old 12-02-03, 09:18 PM
  #41  
IRS Champion

 
enzo250's Avatar
 
Join Date: Aug 2001
Location: NY
Posts: 2,038
Likes: 0
Received 1 Like on 1 Post
Well Cam,

You have to figure out what you want to do. If i was you i would just build another manifold. it would be the easiest way. You have a lot of work to do reworking your existing one.

I know you spent alot of time on it. This time though it will go much quicker since now you have experience.
Old 12-02-03, 09:21 PM
  #42  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
Here is another pic to chew on.

Max, what is the ID of the main runners on that manifold?

Old 12-02-03, 09:26 PM
  #43  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
enzo- making another manifold is last on the list. I would much rather mod this one. If I made a new one I'd have to make a new DP, turbo-I/C tube and oil supply line.
Old 12-02-03, 09:29 PM
  #44  
IRS Champion

 
enzo250's Avatar
 
Join Date: Aug 2001
Location: NY
Posts: 2,038
Likes: 0
Received 1 Like on 1 Post
you can build another one with the turbo in the same spot so you won't need to make new dp. You can build a little jig so you keep the turbo in the same location.
It's easy for me i guess that's why i recommended it.
Old 12-02-03, 09:32 PM
  #45  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
I bigger turbine housing may fix the problem. Anyone know if there is a bigger turbine housings than a 17cm for a TD07 turbo??
Old 12-02-03, 09:36 PM
  #46  
Rotary Freak

Thread Starter
 
setzep's Avatar
 
Join Date: Feb 2001
Location: MN
Posts: 2,524
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by enzo250
you can build another one with the turbo in the same spot so you won't need to make new dp. You can build a little jig so you keep the turbo in the same location.
It's easy for me i guess that's why i recommended it.
I suppose if it came to it I could clamp the exh and I/C tube to the turbo and let it suspend there while I make a new manifold under it. You should have seen the jig I had when I made this one... Involved a piece of wood I found in the garage and a couple coat hangers.
Old 12-02-03, 10:28 PM
  #47  
Freedoms worth a buck o'5

 
Maxthe7man's Avatar
 
Join Date: May 2001
Location: Calgary Alberta Canada
Posts: 2,544
Likes: 0
Received 1 Like on 1 Post
My tubing is 2", my wastegate runners 1.5 inch....I am gonna build another manifold for my new turbo, I am going to stay close to the same design, it seems to work well, My spool up is awesom for a 1.15 a/r turbine, probably partly due to the porting abit though...Max
Old 12-03-03, 12:41 AM
  #48  
10.21 @ 137mph

 
12at's Avatar
 
Join Date: Jan 2003
Location: australia
Posts: 184
Likes: 0
Received 1 Like on 1 Post
I had a similar problem to you with boost control and ended up changing the wastegate pipes direction. At first they were underneath and then went backwards. I dont have as much room as you guys as my steering box and brake booster are on that side. What worked for me was moving them to the top of the runners and in the same direction as the runners. So that the air didnt have to change direction to get to the wastegate.

I have pics but no webspace. I can email them to you if you like.

Last edited by 12at; 12-03-03 at 12:44 AM.
Old 12-03-03, 04:07 AM
  #49  
I can has a Hemi? Yes...

iTrader: (2)
 
Directfreak's Avatar
 
Join Date: Dec 2001
Location: 3OH5
Posts: 9,371
Likes: 0
Received 4 Likes on 3 Posts
Cam,

A Wastegate works mostly off of pressure, and while it's closed, it's all the same. I've seen less efficient looking setups work without any probs.

Route the damn Wastegate back into the downpipe before you attempt screwing your manifold

If your Wastegate doesn't have any backpressure, you will make more power, and more boost creep.

You will also have to Re-tune afterwards.

It you still creep afterwards, (I think the routing back into the DP will help immensely) then the dual WG is the cheapest and easiest way to go.
Old 12-03-03, 02:27 PM
  #50  
Senior Member

 
Fatty_FC3S's Avatar
 
Join Date: Jul 2001
Location: Northern California
Posts: 595
Likes: 0
Received 0 Likes on 0 Posts
Just out of curiosity...


Can you put header wrap on that manifold to control heat in the engine bay? Or is that just too hot and its better to only wrap the downpipe while making a heat shield for the manifold?

Good work on that manifold....


Quick Reply: Help me redesign my WG runners



All times are GMT -5. The time now is 02:08 PM.