I\'m needing info on how the sequential twins opperate!!
I know about the valvs, masses of vacuum pipe etc. but what stops the second turbo from blowing in to the inlet track the same time as the first one?? is there a flap that lifts / mooves at 4500rpm to allow the second turbo to come and play, if so where does it live??
Basicaly I\'m looking at chainging the Ypipe for custom stainless steel pipe work: getting better flow and looks!! if I did this idea would I be removing the sequential set up, and run the twins in tandem :Ladys-man talking turbos guys, 1 women is enough!!!
Some one help!!!!!!
Cheers
Jono
Lots of "how it works " stuff here.
http://www.silverbulletrx7.com.
His site is playing up at the moment but it has stuff about how the turbos work.
Try it later
There is a flap.
Mazda call it the "Charge control valve". It is operated by the "Charge Control Actuator", which in turn is operated by the "Charge control Solenoid".
When the revs are climbing, this flap is held closed so that only boost from the Primary Turbo is in the system. Even when the 2nd Turbo is spooling, this flap stays closed.
At 4.500 rpm , the flaps opens and allows bosst from both turbos to combine.
Note that when revs are falling, this flap will stay open until 3k rpm.
Cheers for that guys.........
Just out of curiosity if I was to remove the Charge controle flap, both turbos would run at the same time continulasly????
If this flap was just removed would i have to do anything with the mass of vacuum pipes or would I be able to leave them as they\'re not opperating anything????
I need all the info I can get, just to see if the plan is viable!!!!
Come on you people in the know..... enlighten me!!
Jono
If all you do is open the charge relief valve permanently without doing anything else to your control system, then the result would be reduced boost - as the primary boost will be dumped down the charge relief system, and vented to atmosphere.
Right OK, how do I get around that then???
Where is it and how does it opperate?
I\'m looking at bining the Y pipe and making a new inlet track to the IC improoving looks and efficiency????
FEED ME WITH YOUR KNOWLEGE!!!
Jono
You\'d have to look into the removing the sequential twin turbo set up. As far as i know, it\'s relatively involved, but still quite easily possible to do. There\'s lots to do on it though.
Look here (http://www.rx7city.com/techconnect.htm) for info on the twin turbo setup.
And look here (http://www.fd3s.net/non-sequential.html) for how to go non-sequential, which is pretty much what you\'re asking to do.
Cheers for that nick, hopefuly this info will come in very handy.
Anyone know the advantages of going non sequential,anything to gain?
Cheers
Jono
There is nothing to gain. You will lose a lot of the 10PSI boost at low revs , the boost will build slowly through the rev range, and at high revs you will have the same boost as the sequential set-up.
QuoteI\'m looking at bining the Y pipe and making a new inlet track to the IC improoving looks and efficiency????
If you\'re not careful, you could be reducing efficiency. I guess you want to bin the Y-pipe to make a bigger pipe, as that can be the only reason for binning the y-pipe and yet remaining twin turbo. Making this bigger will mean the air flows
slower through the pipework. This could also effect boost buildup, and waste the whole point of the twin turbo setup.
My advice would be to get the efini metal y-pipe and polish it up. Replace the stock plastic pipes with metal pipes, and polish the whole lot up. Will look a lot nicer, but will be much the same setup.
Close Nik,
I was looking at having twin stainless pipes the same size (inturnal) as the Y pipe up and across the top of the engine, then blend them into a 3"od pipe for fitting the IC, with the 3" housing my blowoff valve????
No sharp 90 degree bends like the standard y pipe, so should flow better??
Jono
That idea sounds bad to me too: I\'ll try and explain why, but it might be difficult to get my point over.
So, as far as i understand it, you will have one pipe coming from the primary turbo, and one pipe coming from the secondary turbo, both merging into a single 3 inch pipe close to an uprated intercooler. The problem here is that there is more pipework, and if you remain sequential, then unless you move the charge control valve to near to the point where the two pipes merge, you are going to have more air in your pipework, which will take longer to create boost on. i.e. more lag.
However, if you go non-sequential, you end up having more lag, but a bit more power low down once the turbos have spun up. There\'s still more pipework for both the turbos to compress air in, and therefore more lag again.
Personally, it doesn\'t sound like a viable modification. They\'d probably be a lot of work to do on it too. Less work to do on the pipework if you go non-sequential, but then lots to do making it non-sequential in the first place. More work to do on the pipework if you\'re remaining sequential - as you\'d have to fabricate some way for the charge control to work near to where the pipes merge. And i don\'t think there\'s going to be any performance gain in it - i also don\'t think the engine bay would look any nicer: i think it would look more cramped.
But these are only my thoughts and judgements on limited knowledge. You may prove me wrong if you do decide to go ahead with it.
Cheers for your thoughts Nik, I can see where your coming from and can understand your logic.......... It was one of those ideas that come to you late at night that look a good possibility!!!!
I was hopeing to improve the air flow and thus the performance of the car.
but thoughts from people like Dragon and alike would be nice to have???
Jono