FD turbo for Finboy

[Maxt]

first

[Maxt]

2

[finboy]

thanks...still confuses the hell out of me...

i see where the exhaust enters both the turbo's, and the exit point, but i cant figure out why the second waste gate is located where it is.

are the turbo's are the same size?

[Hollywood]

Originally posted by finboy
i see where the exhaust enters both the turbo's, and the exit point, but i cant figure out why the second waste gate is located where it is.

I'm not a rotary expert but I can make a good guess as I know them a little. It looks clear to me that the second wastegate is on the turbine to the exhaust port engine side. I'm guessing their is a flap that stops the entry of exhaust gases for the second turbo, then after the swich over the valve (like a butterfly valve) opens so that the second turbo spools up, thats how you get your 10-8-10 PSI (10-turbo1::8-switchover::10-turbo2).

[legendboy]

stock twins are ass

[Maxt]

�@Yeah Holly wood is pretty close... There is alot more to it than what is pictured there, the second turbo is surged prior to being put on stream, that gets the second turbo up to speed and makes for a smooth transition to boost... If you are really interested in the deep dark secrets of the sequential twins, go to the Calgary Library and take out the book on the FD3s rx-7 by Jack Yamaguchi, the second gen book by him is pretty kickass as well.....
�@Legendboy... FWd cars are ass....:lol:

[Hollywood]

Originally posted by Maxt
�@Yeah Holly wood is pretty close...

Not bad for a piston propellor-head!

Originally posted by Maxt
Legendboy... FWd cars are ass....:lol:

Don't worry in a drunken state a few weeks ago he confessed his desires for RWD! The real legendboy comes out of the FWD closet!

[finboy]

i see, so why is this removed from most fd's?

it seems to me that it would be a great street application, as there would be spool in the low end, straight through to your shift point.

[finboy]

also, what are the specs of these turbo's? A/R? wheel trim?

[legendboy]

Originally posted by Maxt
Legendboy... FWd cars are ass....:lol:

good one.

[Maxt]

Finboy, the biggest problem with this setup, is the same as the TII setup, the turbine is to small once the breathing on the intake side is opened up, and the backpressure along with the extra heat that is retained, ends up cooking the motor... The turbine side is fine for good spool and the amount of air it was originally engieneer for, but aftermarket filters, porting, and higher boost levels, overwhelm its flow capability...
Rotary's love to breath on the exhaust side, you can get to a point pretty easily on the stock turbo, where you can keep adding boost to you are blue in the face but not make any more power, jump up a few sizes in turbine wheel though, and the power will jump in a huge way, as much as 100 hp just with a larger turbine side...maxt

[finboy]

same issue with the turbo dodges, the .48 exhaust side is good to an extent before it becomes a restriction at around 20-22 psi, which is then usually replacesd with a .63...

the rotary has a much higher output of exhaust gas than an 8v four cylender, so what i am kind of wondering, is how well this could be adapted to other motors.

the simple answer is go get a big turbo and stick with it, but if the a/r specs, and trim wheels are within reason, it would make an interesting alternative, esspecially since the RX7 guys seem to like getting rid of this set up.

i dunno, just playing with ideas...

btw, IHI turbo's i'm guessing?

[Maxt]

Yeah sorry They are IHI's I meant to include that... The vaccuum piping for sequentials is anight mare, and thats what made the FD such a fragile car, not sure you want to build that defect into something....Neat idea though..Maxt

[legendboy]

Why not save up a bit and use a properly sized t3/t4? I'll bet even a .60 trim t04b compressor would out flow both of thoes stock twins! + makes for easier fabrication.

[Hollywood]

I dought you could get it to work on a any other car, not to mention getting a twin turbo application to work on any non twin turbo car. Drop you idea's, come to reality and buy a good single turbo.

[finboy]

Originally posted by Hollywood
I dought you could get it to work on a any other car, not to mention getting a twin turbo application to work on any non twin turbo car. Drop you idea's, come to reality and buy a good single turbo.

i have a good sized single turbo (60 trim on the intake side is too big).

but i'm just thinking about what COULD be done.

as for twin turbo's not working on a car that didn't come with them, a guy on turbododge.com has a twin turbo shadow that runs 12.1 full interior, so it can work.

[Akagi Redsuns]

Just FYI, there is a BIG difference between a twin turbo system found in the 300ZX, Porsche 993-996 Turbo....etc and the twin SEQUENTIAL turbo system found in the FD3S RX-7 and the MKIV Supra (and the Porsche 959 if we are being specific).

AFAIK, I haven't seen anyone untilize the twin sequential system from a MKIV Supra or FD3S in another car. I think control is a big issue...hell it barely works in the RX-7 and it's comes stock from the factory that way, lol

[Hollywood]

Originally posted by finboy
i have a good sized single turbo (60 trim on the intake side is too big).

but i'm just thinking about what COULD be done.

as for twin turbo's not working on a car that didn't come with them, a guy on turbododge.com has a twin turbo shadow that runs 12.1 full interior, so it can work.

But I'm sure the guy that has it does not have to ask others on what COULD be done. And there are dodges that run 11's with full interior and a single turbo

If your turbo specs are too big for your car why not sell it and get a smaller one for your needs rather than screw around trying to fab a twin turbo setup that will not work as well as a properly setup single turbo. Why do you think the supra and rx7 guys swap out the twins to a single? Because a single is better unless your a pro dragster.

You have bought too big of a turbo now your trying to rationalize the problem thinking you need 2 turbos to make your car better, when really you just need a better single setup. No need to re-invent the wheel here.

[finboy]

i've got a few turbo's, and i have one that is really decent for my car (t3/tbo 348), still, i believe that would have more lag than an IHI, not much, but regardless..

i figure you have the best of both worlds with the twin sequential set up.

and i thought the rx7 and supra guys ditched it because it became too restrictive on their car.