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-   -   S5 stock manifold, external dump... (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/s5-stock-manifold-external-dump-921634/)

sen2two 09-10-10 04:42 PM

S5 stock manifold, external dump...
 
Here's a sneak peak at this for now. I have been seeing here, and other places, where people want to fix the whole boost creep, and boost dropping off before peak RPM. One way is to get an upgraded Garrett internal gate that is very similar to our stock wastegates, and port the wastegate areas on the turbine housing. This works well for a lightly modded car, but some still need more. Especially if the motor is ported, running higher compression, or runnning a hybrid turbo.

Now it has been done a few times on the much larger S4 manifold. But with the very small compact S5 manifold, and divided runners, making an external dump far more complicated. A few people have also kept the stock wastegate area but separated the down pipe area and wastegate area for an external dump. This still poses a problem with releasing enough exhaust pressure through the holes in the turbine housing. Making creep and drop off less noticeable, but not getting rid of it.

Here is what i am going to do to fix the problem. A one inch hole in each runner, meeting at one point with a 38mm external wastegate.

Pics do much better than words.

(I'll update after it's all welded up and finished, I got side tracked with another project and didn't get t finish)


Holes were done with a bridgeport mill. Now I know not many people here will have access to a machine like that. but its not hard to drill a hole with a hand drill and port it out with a die grinder.

http://i282.photobucket.com/albums/k...D/CIMG0023.jpg

http://i282.photobucket.com/albums/k...D/CIMG0024.jpg





Got some pipe and turned it down slightly in a lathe to fit very snuggly in the holes. I'm all about tight fits, ;)



http://i282.photobucket.com/albums/k...D/CIMG0027.jpg




http://i282.photobucket.com/albums/k...D/CIMG0028.jpg





Cut some pipe and mocked it up. A little trimming and grinding, and this will all fit nicely. There's actually a pretty good amount of room below the manifold to come up with your own design. Just take some measurements and get to cutting!




http://i282.photobucket.com/albums/k...D/CIMG0033.jpg


http://i282.photobucket.com/albums/k...D/CIMG0035.jpg

j9fd3s 09-10-10 06:30 PM

neat!

JustJeff 09-10-10 11:13 PM

Subscribed!

MaczPayne 09-11-10 02:14 AM

Have you seen Blue TII's external WG mod?

sen2two 09-11-10 09:34 AM

I have...

durtled 09-11-10 09:39 AM


Originally Posted by sen2two (Post 10209097)
Got some pipe and turned it down slightly in a lathe to fit very snuggly in the holes. I'm all about tight fits, ;)

thats what she said......but +1 i like it if i knew anything about wastegates i would prolly appreciate it more

BurntOrangeT2 09-11-10 11:26 AM

DAMN!!! More thread like this are always appreciated.

Next step

Make a Write up.

j9fd3s 09-11-10 04:14 PM


Originally Posted by BurntOrangeT2 (Post 10210196)

Make a Write up.

um, why?

step 1, drill two holes

step 2, put pipe in holes

step 3, put wg at the end of pipe

step 4; enjoy

sen2two 09-11-10 04:56 PM

^exactly... This is a "write-up". It's just a picture book instead of a novel.

SirCygnus 09-11-10 05:03 PM

would you be able to do this for people needing this mod?

NoPistons! 09-11-10 05:15 PM

Any competent machine shop should be able to not only bore the holes and slip fit taper your piping but should also be able to weld all this up.

Waiting to see how this turns out even though i'm teetering on the edge of saying "screw it" and putting a 1jz in.

sen2two 09-17-10 12:57 PM

All done... Fits nicely. I will not be able to "test" the car until a week from now. I will be in Costa Rica for 7 days! Little vacation time for me...

I'll update once I'm back...

http://i282.photobucket.com/albums/k...anifoldh-1.jpg

http://i282.photobucket.com/albums/k...anifoldg-1.jpg

sen2two 09-17-10 12:58 PM


Originally Posted by SirCygnus (Post 10210623)
would you be able to do this for people needing this mod?


I can.

Just PM me about it. But like i said, I will be gone for the next week. I can get back to you then.

n0ferz 09-17-10 01:45 PM

Looks nice, whats the advantage of running a wg like this on stock turbo/manifold????

RotaryEvolution 09-17-10 02:04 PM

better boost control for modded cars that are having boost creep issues.

although it's more necessary for S4 turbos than S5.

n0ferz 09-17-10 02:09 PM

Nice, I am interested then. I keep boosting 10-12psi and my wg is connected and everything is stock on my engine.

S4 turbo & Manifold, looks like my wg is not ported!!

Don't know why I cant lower the damn psi the turbo is making lol

cone_crushr 09-17-10 02:56 PM

Cool idea and excellent execution, but I wonder if it's worth the effort. It's like trying to retain the factory ECU with a piggyback - the result is a serious compromise vs a standalone (aftermarket turbo and manifold in this case.)

sharingan 19 09-17-10 03:16 PM

as long as the cost is below that of an aftermarket manifold/turbo and performance is better that the stock W/G setup I can't see why it wouldn't be...

sen2two 09-17-10 03:21 PM

Cost for me:

Turbo manifold - Given to me for free
Pipe - Scrap metal from my school = free
Flange for WG - Scrap also = free
38mm Turbonetics Deltagate - Given to me also, free

I have a few hours of work in it though. But it didnt cost me a cent. I consider this a success.

NoPistons! 09-19-10 11:57 PM

Hell yeah.

Free=win.

sharingan 19 09-20-10 09:19 AM


Originally Posted by sen2two (Post 10221798)
Cost for me:

Turbo manifold - Given to me for free
Pipe - Scrap metal from my school = free
Flange for WG - Scrap also = free
38mm Turbonetics Deltagate - Given to me also, free

I have a few hours of work in it though. But it didnt cost me a cent. I consider this a success.

So can I get one "at cost" ? :lol:

Bamato 09-20-10 01:44 PM

Very cool. Well done dude :)

RotaryEvolution 09-20-10 03:13 PM

i'd say it isn't worth the cost if one had to pay for every part, it is a good idea but not for everyone unless there was no alternative. i'd imagine this project would cost most people $400-500 start to finish to pay someone to do and purchasing parts. that's a good start on some real modifications.

sen2two 09-25-10 10:45 PM

hmmm... 400-500 is far over priced.

Since you would most likely use your existing turbo manfiold. that still has no cost, but for the average person, the cost should be more like this list:

Turbo manifold - Use your existing manifold, free
Pipe - 20-30
Flange for WG - 20 (ebay or elsewhere. Or make your own. peice of metal should be 5 bucks.
38mm Turbonetics Deltagate - 100, or ebay special for 50. or find one used on here or many places for around 50-100

give or take a few dollars, anyone should be able to do this for a total cost of 150 bucks and a few hours time.

sen2two 12-14-10 02:36 PM

Update:

I finally installed this on my car. I can hold boost all the way with no problem now. Another problem I was having was with my 2-step launch control. The car would not build any boost even at 6k rpm. Just tested this and easily build boost off the line.

Proving further that the stock wastegate door in the turbine housing is being forced open prematurely by exhaust pressure. Porting the wastegate can just make this even worse. EBC's will NOT fix this, at all.


:icon_tup:


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