Discussion , Non-traditional Remote Mounted Turbo Systems

[bigal004321]

see two turbos are good in a good way.. but if you look at all the fast cars out there they always upgrade from twin turbos to one big turbo.... single turbos are good for the low end and twin turbos are good for high end....

plus i heard that the most effiecnt turbo is one that is glowing red since it is gettting those hot atoms going threw very fast thus turning the turbine that fast.....

[FyreDaug]

single turbos are good for the low end and twin turbos are good for high end....

Isnt that backwards?

[86AccordLxi]

Yeah, I think it is.

Alex

[justin89]

Yeah, I think it is.

Alex

it is backwards but it all depends on how you stage the twin setup.

[ICEMAN707]

normally the stock twin turbos on the 3000gt's and 300zx's are there versus a big turbo because of turbo lag. two small twin turbos will spin much faster and produce the same boost result when they work together as a slightly bigger single turbo. UNLESS you get a super huge turbo like a t78/t88, then you get more results but it takes a fully built 6 or 8 cylinder engine to spin those with little to no lag.

i dont see how a remote turbo couldn't work. you might get good boost, you might not. it all depends on your piping and turbo size choice. you could have your freeflow piping bottleneck from 2.5" to 2.25" to 2" to increase the exhaust velocity spinning the turbines faster. as the boost kicks in, the more exhaust velocity develops from the increased combustion. it's like a chain effect. of course a good intake and exhaust system is key: cam, Edelbrock Victor X IM (or any good aftermarket brand), freeflow or no cat, headers, polished/ported head and IM, bored out/porter/polished throttle body, etc. etc. ....also the fuel and spark upgrades needed to support all that increased airflow.

anyways, for a remote application, a small turbo is the way to go. to get more boost, you simply need to run twin turbos...or 3 (lol)...with all that space in the back, why not?

particularly good are hybrid turbos like a t3/t4. a big turbo probably won't spin fast enough that the only way IS to have them mounted right at the exhaust manifold exposing them to hot engine conditions. shit, if you can get small stock turbos cheap enough from junkyards, you can try running 3

either on fork Y-split:

0---\
0---->----
0---/

or along the pipeline in a staged setup: -----0--0--0

of course with all those turbos your car would sound like a turbine jet engine that's a lot of intake and exhaust piping, oil lines, and vaccum lines for the wastegate actuators to run though. or if you have turbos that have coolant lines, that's additional too.

[A20A1]

Too much pressure.
>

Well I've looked and looked for a definative answer to reversion and everyone seems to be floating aound the same area but not in the same way. So I'll try to make some sense of it.

They say exhaust gasses can either be pushed or pulled into the intake via reversion.
The problem is which is it or is it both under different circumsances?
The timing of the events differ slightly also.

We know it's a pressure difference between the intake, cylinder, and exhaust. But also the valve timing and tuned length of the header and intake.

Some argue that reversion is the Intakes fault while others say it's exhaust, and then there are those that say it's both.

Some say it's a positive pressure that causes reversion while others say that the negative returning wave is the reversion wave, but they offer no explanation on how this adds to scavenging, though some say that it is the reflected wave off of the closed exhaust valve that creates the scaventing.

What I've read and come to understand the negative wave as the expansion wave, which is supposed to move exhaust gasses opposite the direction the wave travels in, thus it creates a suction, this is the scavenging wave.

So when if at all does this positive wave come into play, I don't think it does unless it's a refelcted positive wave from a muffer baffle or a cone in the exhaust pipe with a decreasing diameter. Since a positive wave would push gasses back towards the cylinder.
Supposedly a reflected wave from a closed exhaust valve will still be negative and so it will flow gasses in the opposite direction that it travels in. So if the reflected wave travels away from the exhaust valve, that means it draws exhaust gas back towards the cylinders.
I could be wrong though.

Most agree the reversion takes place on the upstroke as the intake valve is opening and the exhaust valve is open (Overlap Period). This is when you want the scavenging wave to meet so that it daws out all the gasses.


https://www.3geez.com/showthread.php?p=537346

anyways, turbo pretty much negates the pressure waves, but I tried to add some things on why heat is important, in the last post.

Make corrections where needed, I'm pretty tired so I didn't double check my post.

[Justin86]

justin why are you always smilin' bro? lol. is this what you did to your "tasha" and it works?

Well I'm a crazy mo fo and you can never tell for sure. After taking a look over some of the new semi trucks and their twin set up got my gear turning. If you have seen one you know how they are set up but watching the boost gauge on these huge things climb up to 58 PSI is sweet. So what I could to is run 2 T3's in seires have something that is caple of making 25PSI easy and still have fast spool up. Of corse this means i need to go with a fully built bottom end and trans which i haven't done YET.

But think about making 400hp and not to have to worry about the huge lag from the todays typical huge turbos

[PikesPeak3G]

Just Another outside the box thought. How about the turbo being mounted just in front of the trunk where the fuel tank is. The tank being removed would open a space where the turbo would be tucked out of harms way, it would allow a straight shot of exhaust from the header with little or no bends, the oil can still come from inside the trunk where obviously the racing fuel cell would be(which would probably be lighter), and it would facilitate setting up a high flow electric fuel pump. The exhaust gases would also be flowing hotter if thats a the point someone was trying to make before. Just food for thought.

[Robs89LXi]

I think there is some confusion here about twin turbocharging and sequential turbocharging. Basically, twin turbocharging uses two turbos in parallel, such as in a V-engine arrangement where each turbo is supplied by it's own bank of cylinders (in a V-8, four cylinders go to one turbo, while the other four supply the second). Sequential turbocharging uses two turbos also, but they are set up in "series". However, it is not what people think, where the first smaller turbo boosts up quickly, then supplies the second one so it can boost. In sequential turbocharging, after the first smaller turbo hits max boost, it's exhaust gas supply shuts off, and the exhaust flow now powers up the second bigger turbo. Another way is to have the gas from the first turbo shunted through it's wastegate when it reaches max boost, so it then supplies the second one. Bottom line though, is that it is not the boosted air from the first turbo that powers the bigger one, but rather the same exhaust gas, just now already up to speed enough to bring the bigger on to boost. So you see, just hooking two turbo's up in line is not sequential turbocharging. Now, is that as clear as mud?

[Robs89LXi]

As for reversion, read here (if you can):
http://personal.riverusers.com/~yawpower/techindx.html

[Accordtheory]

Robs89lxi, thanks for.. clarifying this thread a little. I didn't even know where to start.

..so there is some type of valve on the intake side of the smaller turbo that closes once it's exhaust supply has shut off (..since air will flow backwards through a non spinning compressor)? how do they connect all these valves and collectors in an aerodynamically acceptable way?

maybe that is why sequential systems are never used for max power applications, like a 1000whp supra..

[Robs89LXi]

Exactly. The complexity of valves, added weight, and extremely narrow tuning range make sequential systems very hard to work with, much less fabricate. With the advent of ball-bearing turbochargers, better intercooling, and sophisticated engine management now, turbos are able to spin to much higher RPMs, thus stretching the boost range (efficiency), and negating the need for more than one turbo.

[Robs89LXi]

Oh, as for STS; I've contacted them several times, over about a year span of time, and they have still done absolutely nothing with that Acura project. I think their principle of a rear-mounted turbo is fairly sound, but I'm not sure it will be very good with four cylinder application. I just don't think we can move enough volume of air fast enough to get a very efficient turbo. Until someone tries it though, I guess we will never know.
Just do what I plan to do; mount the turbo on the back of the block. First, I'll have to install a remote oil filter system to get it out of the way, but once that is done, there will be plenty of room for a turbo. I've already test fitted one from a Ford T-bird Turbo Coupe, and it fit just fine. A regular header design would now be possible, just turning up a bit behind the engine, and of course ending with a T3 flange. I'll get to keep my A/C , oil lines will be a breeze, cooling for the turbo from air beneath the car will be nice, if you are not planning on running an intercooler, plumbing will be real short, and best of all, I'll get the stock "sleeper" look .
To each his own though.

[Accordtheory]

that's an interesting idea. I advised another member on this forum to do something similar to that, use the stock manifold and mount the turbo wherever, maybe at or near the battery location, but the rear mount might actually be better. I'm curious to see a picture of it, that sounds like it could qualify for major sleeper status.

p.s. Do you know if anyone makes a variable a/r ratio turbo big enough for 600whp yet? That is where the future is.

[gr3k0sLaV]

For people who've done their own manifolds, where did you source the flanges from? or did you cut up your own ones?

How difficult would it be to mod our factory manifolds? could it support the extra weight or not?

[Accordtheory]

don't even bother. just remote mount the turbo.

[A20A1]

Maybe you could weld a flange to the cast iron manifold... use an LX manifold, the 3 bolt flanged down pipe port could be used as the wastegate exit and you can weld the turbo flange on the front surface of the manifold, that would keep the turbo from hitting the beam below the manifold... hopefully the wastegate is small enough to fit.



That sharp turn in the exhaust isn't the best for flow though.

If you have good welds it should support the weight, there is a heafty bracket about midway down the manifold that bolts to the block.

This way will probably hit the radiator though.. so whatever you do you're running into space issues.
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[gr3k0sLaV]

don't even bother. just remote mount the turbo.

I' don't understand this remote mounted turbo concept.

I might try and find an old manifold and take a look, anything is worth considering.

[A20A1]

The difference is the turbo size and the extra expendature from running longer exhaust and intake pipes... put you should properly heat coat them to keep your system efficient. But you do have limitless space in the rear.

REMOTE TURBO
STS ( SQUIRE-TURBO-SYSTEMS )
* With a properly sized turbo the remote mount system can offer many benifits; Cooler Turbo, Oil, and Engine Temperatures are some of the benifits.
They do offer a coating for the exhaust pipes to retain as much heat as you can from the header all the way back to the turbo, this will retain thermal efficiency.

[gr3k0sLaV]

The difference is the turbo size and the extra expendature from running longer exhaust and intake pipes... put you should properly heat coat them to keep your system efficient. But you do have limitless space in the rear.

REMOTE TURBO
STS ( SQUIRE-TURBO-SYSTEMS )
* With a properly sized turbo the remote mount system can offer many benifits; Cooler Turbo, Oil, and Engine Temperatures are some of the benifits.
They do offer a coating for the exhaust pipes to retain as much heat as you can from the header all the way back to the turbo, this will retain thermal efficiency.

Hmmm, only issues though is longer piping for the turbo to intercooler.

[gr3k0sLaV]

The remote turbo setup looks interesting, done some research.

Basically the systems run straight off the factory exhausts after the cat.

Problem though what about heat loss between the engine and the cat? or is it something that header wrap could fix.

---

From what i've understood--

1. Turbo is mounted at the back and is attached straight after the cat.
2. Air intake is directly under
3. No intercooler seems to be necessary since much of the air is cool betweenm the turbo and intake.
4. Electric oil pump is used to run oil to and from turbo.

So this system appears to simplify things. Although i'd be guessing header wrap straight fro mthe header to the turbo would help.

Also for those wanting mid-low boost, be better off keeping the facoty exhaust to keep exhaust velocity up rather than using 2 1/4 exhaust piping?

Still the system looks more DIY friendly.

[gr3k0sLaV]

Just an update I made a contact today, some importer setting up a new business specialising in conversions, halfcuts, turbo's, actually everything .

$200 AU for T25 turbo with no shaft play, used but otherwise great condition.
$300-500 for custom intercooler
$400-500 for custom turbo manifold $400 for manifold or $500 for manifold with coating.

Microtech aftermarket ecu $1500 approx for that sensors and coils.

The price I can get a manifold and turbo sounds very interesting.

My major questions are
a) how much can our stock injector & Fuel pump handle. I actually have a set of brand new Injectors from a 6cyl Turbo car, might post some photo's of 'em got the sitting around doing nothing. Wonder if I can make use out of them.....

just see if i can fit them in the accords manifold

[gr3k0sLaV]

Injectors I got are

Bosch 0-280-156-123 can't find any info on 'em though

anyone got any suggestions on where I might find info

[Accordtheory]

i didn't mean remote mount the turbo in the middle of bumfuck egypt, I meant keep it in the engine bay, maybe behind the engine under the intake, or off to the side where the battery is. By the way, a t25 is way too small..

[gr3k0sLaV]

Behind the engine could be done, looking at it last night, you'll have you work around limited space getting the exhaust piping around the drive shafts. Where the battery goes isn't a dumb spot, i've seen it done on homemadeturbo somewhere.

T25 maybe a little small, but would provide decent low end boost which is what i'm after. - Why do you think it's too small?