Cheap DIYS Stock Turbo Y Pipe Mod
 

Helps eliminate interference. Saves some wear and tear on you turbos and free's up a couple hp. Especialy in sequential mode. Great for Non-Sequential too for that matter. If you have a stock car this is a great mod that doesnt require a computer change or anything else for that matter to help the performance/longevity of your car. Great for Non-Sequential too for that matter... This mod recieved rave reviews in RX-7 Magazine over here in Japan. It will also work with the new style hard pipes.

(Note: I still think seq sucks as far as race tuning is concerned)

Just as in the picture... Take a hard pad grinder and cut a slit along the bottom and sides of the pipe big enough to fit a piece of sheet metal through. (high enough up the sides so you can get a weld on the sheet metal twards the top for rigidity) Cut the sheet metal to fit through the top opening. Once the sheet metal is up there then just cut the remaining off of the outside of the piping. Then weld it along the seam. Even if you cant weld or dont have a welder just do the mod then take it to a muffler shop or something to make the final weld, thats what I did, they shouldnt charge much at all just for a simple weld.

Sorry if its been posted before but I did not see it anywhere.

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Re: Cheap DIYS Stock Turbo Y Pipe Mod
 

Let's hear the reviews. What HP numbers were gained, and what's the primary function?

This sounds pretty cool, but yeah i'm curious as to exactly how this is supposed to help.

"Helps eliminate interference" -Jesse

It directs the air flow from the turbine to the engine as opposed to the other turbine... efficiency...

A small difference but a difference none the less.

I read in a book about turbo.
Actualy if they are running parallel (non-seq). You want them to come together, it will create turbullence which is good for directing the flow.
Maybe I am wrong, don't remember, but there was a drawing somewhere.

reza

Which RX7 mag? Sounds interesting... I have an extra stock y pipe.. might as well try it.

Could you find that book, and quote it to us? I would like to know the specifics of not doing this set up.

That makes perfect sense. Might help a little with lag.

Its in this book.
I have the book at home, but don't have working scanner.
http://www.amazon.com/exec/obidos/tg...oks/0895861356

Thanks for the link. Screw the scanner, just type the passage from the book. I have the chance to do this mod, but if it doesn't work well with non-sequential I wont do it. It makes good sense to me that it would help, but if the book says, no it's a bad idea to split the streams, then I dont know.

Im gonna break out the dremel and try this. Can you do a diagram of how far down you cut?

Also, what did you do to accomodate for the curvature-- Is it perfectly round, or oval? (diameter size would help)

It seems like a logical thing to do... I dont see how the plate would restrict that much flow since it is only split within the y-pipe. If the airflow from one turbo is going at a faster velocity than the other, it should 'pull' the lower velocity air causing a marginally faster spooling time. Should be a lot less turbulence within the coupler than if the air was to mix within the y-pipe, where the charged air comes in at colliding vectors.

What a great idea...this really does make a lot of sense, as the two directed flows from the two turbos are indeed facing each other, wasting energy in the form of additional heat being added to the air.

Okay, I got it on digital camera.

I think it may not actually apply for RX-7.
The theory is for V8 engine that has parallel turbos for each banks.
https://www.rx7club.com/forum/attach...postid=1047715

whole page

wholepage

i would imagine that splitting the turbo's compressed streams like that would make good sense, but wouldnt it also add a lot of restriction to the air flow of the turbos? im just curious because instead of splitting it up into two 3 inch pipes, it cuts it down to two 1.5 inch baby pipes, so wouldnt this kinda "constipate" the turbos, like if you were to try to take a shit through two small assholes instead of one normal one?

that might be true if it were two 1.5" pipes all the way to the intercooler

how do you figure that? he's splitting up one three inch pipe in half, so he's not losing any area. it's not equivalent to 1.5 inch pipes.

[QUOTE]like if you were to try to take a shit through two small assholes instead of one normal one?

Yeah, I prefer the one normal hole too.:tear:

Seems this would make more sense if you could find a metal strong enough to handle the blast furnace inside the common manifold out of the turbos. Since at moderate boost levels you get exhaust gas reversion(like in the V8 diagram above post) the turbines are fighting against each others pressure waves of exhaust gas. It seems that a strategically placed and welded piece of inconel or other stout material protruding from the down pipe and fitting snugly into the turbo manifold common outlet to shelter exhaust gas from each turbo would make a large difference at higher boost levels(ie 18 or so psi).
art

Well, if your read the fine print, they are concerned about even distribution of fuel mixture to each intake runner. Flow does not seem to be a concern. I would think that this modification would help smooth air out, and perhaps increase perfomance. I would like to see some dyno numbers to back it up.

The excerpt with the example from the turbo V8 doesnt apply, since its merely saying that turbulence is needed to better mix the air/fuel, which is an unrelated matter. I think there are really too many variables to say off the bat whether this would work or not. It depends on things like what kind of flow there is in the pipe (laminar or turbulent, I would think the latter), or whether the additional vortices created at the right angled corner from the metal barrier/pipe interface would offset the gains.

Unless you personally have a glass smooth intake track, I think we can throw out laminar flow and assume that turbulence wins.

Right on.