****. you. you need an attitude adjustment ********.

most helpful info/response in the whole thread.

 

GT2860RS (Disco Potato).....................3.549................. ..3.105.................... 87%
FC T2 (OEM).........................................3.57 9....................4.288................... 119
GT3071R........................................... ....4.776....................4.019................ ... 84
GT3071R........................................... ....4.776....................3.683................ .... 77
GT2876............................................ .....5.224.....................3.108.............. ..... 59
TO4E 57 Trim........................................5.369. ....................5.408 (Stg 5)......... 100
GT3776............................................ .....5.374.....................5.441.............. ...... 101
TO4E 60 Trim.........................................5.476 ....................5.408...................... 98
GT3076R........................................... .....5.511...................4.019................ ....... 73
Turbonetics 60-1....................................5.647........ ...........5.89....................... 104
Turbonetics T61......................................5.79..... ............... 5.89......................101
TO4B 62-1..............................................5.8 7..................... 5.89...................... 100
FD (OEM)............................................. ....5.972.................5.25.................... ..... 88
this is what spawned this question in the first place, taken directly from the stickies in this section.

 

Awesome, your profanity and name calling further reinforces our assumptions of your intelligence level, bravo my friend! Keep in mind this is an open forum and your profanity is a bit extreme. Think of the things allowed on radio and tv, then think of what's not allowed in either and that's what should be deleted or refrained from being used here as well.




OK, so looking at this chart NONE of the numbers between the FC and FD correlate, not one bit (not by half, not by double). I assume you saw these numbers and came to the conclusion that one FD turbo of the twin system is the same size as the one turbo off an FC. How the hell did you come up with THAT assumption looking at this chart??????

arghx gave u a great and detailed explanation, little did he and probably EVERYONE READING this know that you meant ONE turbo from the twins. You should thank him for his time and attempting to help, then let this useless thread die off and save yourself some face by refraining from posting any further brilliant responses. You got your answers to your questions. I apologize for coming off abrasively at first, but if you've ever been on forums you'd understand the frustration of repetitive questions being annoying when all you have to do is search. Again, your question would not have yielded your specific answer, your original post was not clear at all as to what you were getting at, and it still isn't clear (the whole chart being your basis for assumption that one FD turbo can replace the single on a fc).

~Mike...... <----- signing out this thread

 

OP, I see where you are coming from. You are looking for an upgrade while trying to keep things on the inexpensive side. The FD twins are not the answer my friend.

Look into a series 5 TII turbo as an upgrade (89-92), if you have a S4 (87-88). If you are looking for more power than an OEM turbo, than your going to have to start looking at the few TII kits manufactured, or piece together a kit.

 

So here's some light on this subject

I have an na s4... I have fd twins and stock fd ehuast manifold..

I AM going to make this work... for everyone who says it can't be done....


......I will do it.!

I have stock LIM modded removed acv flange no 5th and 6th ports... still more things in the worx..

 

have fun w/ that. Go make it work. When it doesnt work the way you want let us know. If you have played w/ the twins on a FD and know how much a a nightmare they can be troubleshooting them and the soleniods you would not even consider them.

Good luck.

 

This thread made me giggle

 

Answer this question: have you confirmed that there is clearance for the FD turbo assembly with your modded LIM?

If you can fit it in there, you can make this work. I've already proposed how to run them sequentially in a longer thread in the 2nd gen section. It involves using 5 MAC 3 port solenoids ($26 each), all triggered by a single rpm switch (Rtek 2.1 can also be used to trigger it).


I will now reproduce the information here.

 

In this case let's assume you are running at the spring pressure of 7-8psi. The OEM FD solenoids are known to be problematic, but you should be able to use aftermarket 3 port solenoids, same as the Haltech/AEM boost control soleniod, to control the twins (viton check valves are an upgrade as well).



available here for about $26 each: http://www.frightprops.com/FrightPro...ID=A-0013-0082

the factory solenoids look like this:



You will need 4 or preferably 5 of the MAC solenoids if you want to keep the wastegate shut just like Mazda does from the factory. Then you will need an rpm switch (or you can use an Rtek) such as this cheapo one: http://www.racerpartswholesale.com/p...ue_Shift_Light

If you have the stock ECU/Rtek you will need a custom TID that splits from the AFM to the two turbos. You can also use dual MBC's or a single external EBC. There's more than one way to do it.

 

Here's a diagram of the main actuators in the system:

 

That's the factory FD control logic for very low throttle. At high throttle the transition point is 4000rpm. So at 4000rpm (you could still adjust the rpm later) you will need to switch your charge control, charge relief, the two turbo control solenoids, and you will want to begin opening the wastegate. Technically the charge relief solenoid isn't supposed to come online until at least 2000 rpm (which would require a window switch), but I don't think it matters that much. So here is one idea:



Under 4000rpm:

-- Charge control actuator receives vacuum from vac chamber
-- Charge relief receives vacuum from vac chamber (valve opened)
-- Turbo control actuator (pressure side) is vented
-- Turbo control actuator (vacuum side) is vented
-- Wastegate is vented (held shut to improve spool), 2nd port on actuator capped
-- Pre control valve is connected directly to the compressor outlet to control boost via spring pressure, 2nd port on actuator capped. An EBC or MBC could also be used.

Over 4000rpm:

-- Charge control actuator receives pressure from compressor outlet
-- Charge relief valve vented (valve closed)
-- Turbo control actuator (pressure side) receives pressure from chamber
-- Turbo control actuator (vacuum side) receives vacuum from chamber
-- Wastegate receives compressor outlet pressure in order to control boost. An MBC or EBC could be installed in-line
-- Pre control continues to receive compressor outlet pressure and is thus held in the full open position.

I've never actually tried that exact plumbing personally, but on paper it should work. If you look at the stock solenoids, they are just 3 port valves just like the MAC valve I have posted here. The main thing that's different among the solenoids is the configuration of the ports. This has to do with the vacuum and pressure control logic inherent in the system. Some actuators are meant to be vented and then supplied pressure. Some are meant to have vacuum and then boost, whatever. It's no different than wiring up a circuit with a bunch of 5 pin relays. A 3 way solenoid valve works exactly like a 5 pin relay. You have a normally open point, a normally closed point, and a common point that is always connected to the other two. Then there is a coil to switch them on and off.

Good luck. I'd love to see someone pull this off on an s4 n/a--not because it's that great of an idea, but just for all the haters out there.

 

i have been thinking about doing this for quite some time on my s4 t2 block with s4 na rotors. should be fun.

 

I bought "rich mans" non seqt. And not going back to seqt. I have almost finished modding my LIM its going to be a tight sqeeze. But I'm like 80% sure its gunna work..

I've been slammed at work and haven't been able to get a few hours to get to my moms house to work on my 7. From the looks of things I really do think I can make it all fit!

If the LIM doesn't fit and the HT12's can't fit with a small spacer. And it hit the frame or anything I might just get a whole T2 intakes. But we will see.!!

 

This is pretty easy to do.

Is it worth wile? Maybe if you have the parts sitting around or can get them really cheap.

The biggest issue with this swap is going to be water pump clearance. The front turbo sits so close to the lower outlet that you cant get a hose on.

The quickest way to fix that is with a first gen water pump housing (even though one stud wont work. Or cut, angle and re-weld the stock housing.

But just like it has been said before, if you have to ask, you probable don't have what it takes to do it.

Also, NO WAY in hell is it going to clear a 6port lower intake manifold, even with a spacer.