Pat's Ebay Turbo Compound Boost Build - Page 3 - Miata Turbo Forum -Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Build Threads Building a motor? Post the progress here.

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 02-03-2016, 05:53 PM   #41
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Quote:
Originally Posted by shuiend View Post
Here is my post with how it fits on the car. A few posts later I posted pictures I took last night of it with a FM cast elbow.
It doesn't look that bad in the pics. Guess I'll see, I think mine arrives tomorrow or friday. I'm planning to port it a bit for the wastegate if needed, since I'll need lots of flow for that. Not even sure if a 38mm gate and the turbo's internal gate will be enough, but we will see.

Quote:
Originally Posted by 18psi View Post
Of course all the fun happens when im on vaca and have limited internet access lulz
My goal is to be driving it compound boosted by 2/12/2016, next friday. Not sure I can pull that off, but that's the goal. I've taken a few pics, will post some tonight when I have something done worth showing. Still working on the turbo mounting system in the rear, but I got the turbo placement nailed down and a T4 to 3" adapter made and bolted up.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 04:10 PM   #42
Moderator
iTrader: (9)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 13,396
Total Cats: 1,016
Default

Quote:
Originally Posted by patsmx5 View Post
Every compound setup I've seen uses turbos, not a SC, so I said screw it and do what works.
Production cars, Group B Rally cars, and other fun things back to warbirds in WWII had both a turbo and a supercharger. They work well together.

The low-down on twin-charged engines

https://en.wikipedia.org/wiki/Twincharger

The Turbosupercharger and the Airplane Power Plant
sixshooter is offline   Reply With Quote
Old 02-04-2016, 04:29 PM   #43
Junior Member
iTrader: (2)
 
Join Date: Apr 2010
Location: albion, mi
Posts: 263
Total Cats: 13
Default

I was gonna say, only recently have you seen compound charged vehicles become popular, I.e. the diesel crowd. So, pat, just exactly what the hell are you talking about?

And those compound systems literally put the top turbo on the other, not with 6 feet of charge piping between them, so I'm confused about how your system is going to function.

I get the theory, just confused on exactly how it's supposed to act as a twin charge. Are you feeding the rear turbo into the inlet of the forward? Vice versa? Are both being plumbed into the intercooler, and gawddammit one of em shoot push air?
glade is offline   Reply With Quote
Old 02-04-2016, 05:14 PM   #44
Moderator
iTrader: (9)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 13,396
Total Cats: 1,016
Default

So, slow the whipple down to a speed where it is more efficient and rear mount a turbo at about 10-15psi so it doesn't make lots of inefficient heat either. Boom boom.
sixshooter is offline   Reply With Quote
Old 02-04-2016, 05:23 PM   #45
Sadfab Union President
iTrader: (2)
 
Join Date: May 2014
Location: Kansas
Posts: 2,686
Total Cats: 113
Default

All he needs is a small turbo up front for response, then a large enough wastegate to allow the rear turbo to spool still while letting the front turbo level out in it's efficacy island, no creep disturbing flow out back.

The lag on the big turbo and charge pipes ought to be nearly undetectable.

At least that's how I understand what he's doing now.
deezums is offline   Reply With Quote
Old 02-04-2016, 05:25 PM   #46
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Quote:
Originally Posted by sixshooter View Post
Production cars, Group B Rally cars, and other fun things back to warbirds in WWII had both a turbo and a supercharger. They work well together.

The low-down on twin-charged engines

https://en.wikipedia.org/wiki/Twincharger

The Turbosupercharger and the Airplane Power Plant
If I did a twin charged setup that bypassed the SC, I would have a smaller SC (wouldn't need a huge one anymore) and put the turbo up front.

Quote:
Originally Posted by glade View Post
I was gonna say, only recently have you seen compound charged vehicles become popular, I.e. the diesel crowd. So, pat, just exactly what the hell are you talking about?

And those compound systems literally put the top turbo on the other, not with 6 feet of charge piping between them, so I'm confused about how your system is going to function.

I get the theory, just confused on exactly how it's supposed to act as a twin charge. Are you feeding the rear turbo into the inlet of the forward? Vice versa? Are both being plumbed into the intercooler, and gawddammit one of em shoot push air?
As the title says, Compound Boost, not twin charged.

The air path will be: Air filter, Big turbo, small turbo, intercooler, intake manifold.

The exhaust path will be: Cast Iron Taco manifold, small turbo, downpipe, catalytic converter, glasspack, large turbo, some type of muffler/glasspack, out the rear of the car.

Small turbo in normal spot, large turbo in rear of vehicle.

Essentially think of it as normal turbo setup, but at high revs, the normal turbo gets a "boost" of compressed air from the big turbo to up the HP some more.

Quote:
Originally Posted by sixshooter View Post
So, slow the whipple down to a speed where it is more efficient and rear mount a turbo at about 10-15psi so it doesn't make lots of inefficient heat either. Boom boom.
Maybe one day, going to build a regular compound setup for now.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 05:26 PM   #47
SadFab Sales Lady
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 14,798
Total Cats: 931
Default

Will the big turbo be a giant restriction while trying to spool the small turbo?
aidandj is offline   Reply With Quote
Old 02-04-2016, 05:26 PM   #48
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Quote:
Originally Posted by deezums View Post
All he needs is a small turbo up front for response, then a large enough wastegate to allow the rear turbo to spool still while letting the front turbo level out in it's efficacy island, no creep disturbing flow out back.

The lag on the big turbo and charge pipes ought to be nearly undetectable.

At least that's how I understand what he's doing now.
Yes, this is correct. It will drive like a regular turbo miata from idle until the small turbo is spooled and pulling, then somewhere around 5,000 the big one will seamlessly spool up and prop up the top end power a lot.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 05:27 PM   #49
SadFab Sales Lady
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 14,798
Total Cats: 931
Default

I think instead of all this you should get an he351ve vgt turbo. And run allofthe boost.

Cheap, easier, better all around.
aidandj is offline   Reply With Quote
Old 02-04-2016, 05:28 PM   #50
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Quote:
Originally Posted by aidandj View Post
Will the big turbo be a giant restriction while trying to spool the small turbo?
T4, 1.05 AR turbine, 77mm exducer. Hard to call it a giant restriction. My catalytic converter, or old muffler, were both likely more restrictive than this turbine while the little turbo is spooling.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 05:29 PM   #51
SadFab Sales Lady
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 14,798
Total Cats: 931
Default

I meant the other way. Intake restriction.

Do an he351ve instead.
aidandj is offline   Reply With Quote
Old 02-04-2016, 05:29 PM   #52
Sadfab Union President
iTrader: (2)
 
Join Date: May 2014
Location: Kansas
Posts: 2,686
Total Cats: 113
Default

Wouldn't blowing through the little turbo overspool it, choke it, whatever? Wouldn't it be better to just Y them together at the intercooler?

If the big turbo is stalling little turbo spool you should look into vacuum operated wastegates, then you could hold big turbo wide open till 4K, let the little guy breathe. A little electric vac pump should be enough to actuate it.
deezums is offline   Reply With Quote
Old 02-04-2016, 05:30 PM   #53
SadFab Sales Lady
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 14,798
Total Cats: 931
Default

Quote:
Originally Posted by deezums View Post
Wouldn't blowing through the little turbo overspool it, choke it, whatever? Wouldn't it be better to just Y them together at the intercooler?

If the big turbo is stalling little turbo spool you should look into vacuum operated wastegates, then you could hold big turbo wide open till 4K, let the little guy breathe.
Y them toghether would send all the boost back towards the big turbo.

Run an he351ve
aidandj is offline   Reply With Quote
Old 02-04-2016, 05:31 PM   #54
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Quote:
Originally Posted by aidandj View Post
I meant the other way. Intake restriction.

Do an he351 instead.
No it won't, it will help it actually.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 05:34 PM   #55
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Quote:
Originally Posted by deezums View Post
Wouldn't blowing through the little turbo overspool it, choke it, whatever? Wouldn't it be better to just Y them together at the intercooler?

If the big turbo is stalling little turbo spool you should look into vacuum operated wastegates, then you could hold big turbo wide open till 4K, let the little guy breathe. A little electric vac pump should be enough to actuate it.
Blowing compressed air into the small turbo won't overspool it, the turbo will just compress it further and send it to the intercooler. But all that extra air has to escape, and the T2's wastegate/turbine is too small. I'll be running two wastegates up front, a 38mm external gate, and the T2's internal gate as well. I don't know if this will be enough, will have to build it and find out. Going larger than a 38mm gate would require some extra work so doing the 38 for now.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 05:39 PM   #56
Sadfab Union President
iTrader: (2)
 
Join Date: May 2014
Location: Kansas
Posts: 2,686
Total Cats: 113
Default

My only advice is lay out the IWG flapper on the turbine housing, trace it out as much you can and open the hole up to within 1-2mm of the flapper diameter. Diameter is more important than blending, everything in the turbine housing is under pressure and will blow out if blended or not.

For some reason all the china turbos I've seen have midget holes compared to the flapper. I assume it's because they're meant to be universal, lots of output flanges need to work.
deezums is offline   Reply With Quote
Old 02-04-2016, 05:41 PM   #57
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Quote:
Originally Posted by deezums View Post
My only advice is lay out the IWG flapper on the turbine housing, trace it out as much you can and open the hole up to within 1-2mm of the flapper diameter. Diameter is more important than blending, everything in the turbine housing is under pressure and will blow out if blended or not.

For some reason all the china turbos I've seen have midget holes compared to the flapper. I assume it's because they're meant to be universal, lots of output flanges need to work.
Thanks, will do. I'm gonna do the same on the external wastegate part of the manifold, it's china and the hole is maybe 1" for a 38mm gate... Very undersized.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 05:50 PM   #58
Elite Member
Thread Starter
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 7,953
Total Cats: 127
Default

Also I got the turbo mounting system like 95% done. Going to finish that up now. Then I think run the boost pipe to the front if I have all the reducers to do so.
patsmx5 is offline   Reply With Quote
Old 02-04-2016, 05:57 PM   #59
Boosting since 1984
iTrader: (1)
 
stefanst's Avatar
 
Join Date: Sep 2011
Location: Levittown
Posts: 994
Total Cats: 38
Default

Pictures of what you have so far please? I need to see it to believe it!
stefanst is offline   Reply With Quote
Old 02-04-2016, 05:59 PM   #60
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 33,152
Total Cats: 1,990
Default

My guess is smaller turbo's hotside will choke and you will need to run massive ewg or something. and route it back into exhaust otherwise big turbo won't do nothin
18psi is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Garrett BB CHRA pressure differential from loose V-Band housing cause oil leak Landrew Engine Performance 13 02-15-2016 05:12 PM
Whipple Virtual Dyno Results patsmx5 Supercharger Discussion 68 02-08-2016 06:44 PM
Help with my noise rear 90 Turbo Suspension, Brakes, Drivetrain 5 01-14-2016 09:49 PM
Turbo Miata & ODB2 eurojulien DIY Turbo Discussion 10 01-13-2016 09:59 AM
Cost Effective Upgrades?? andyvo DIY Turbo Discussion 23 01-06-2016 08:27 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 03:54 PM.