Tuesday, April 17, 2007 - 09:49 pm, by: Sebastian Boyd(Wanted)
I'm selling my TT in search of some thing more, so i'm trading my TT for a V8 and planing to go twin turbo.
Just doing some research and thought since the turbo's will be at opposite sides of the engine would it be a better idea for response to have 2 small intercoolers in stead of running piping around from one turbo to another and binding it together into a single intercooler.
That way i could have the intercoolers just below each turbo with minimal piping and have the cold air from each intercooler head up both sides of the radiator and join at the top to run into a custom intake manifold that opens from the front near the radiator rather than the left side of the engine for smoother and quicker airflow, any thought?
Wednesday, April 18, 2007 - 06:00 am, by: Ben Lipman(Ben12a)
All the successful TT V8 setups I have seen have a single front mount with twin entries and a single exit straight into the plenum. That is, the core runs vertically with inlet at the bottom and the exit up top. These had custom radiators also.
I have seen (on 300ZX) one large intercooler with two smaller end tanks on each end which make it act as a twin intercooler. I think it was done purely due to solve a packaging issue due to the tight nature of the engine bay.
I have no first hand experience with Twin Turbos on V motors, though. I guess as long as the intercoolers get adequate airflow then it should be fine.
Wednesday, April 18, 2007 - 06:49 am, by: Paul McConnell(Pt1)
Where are you going to put these small coolers so that they are exposed enough and are easy to plumb and effective?
Have a look in the bay and do some measurements of where the piping could realistically go for each setup and see which is shorter. The outlet from the single intercooler will go straight down the throat of the plenum theoretically whereas the piping from 2 SMIC's will have to move around the radiator. Do some real measurements so there is at least some data to work with.
My personal pref would be a big single, if it could be packaged properly, due to simplicity.
Wednesday, April 18, 2007 - 08:49 pm, by: Phil Gibson(Sciflyer)
centre-mounted cooler as per usual, but with an inlet on either side for each turbo and one outlet to whatever direction your intake is
Like this
Also, its my belief that in a stock soarer engine bay twin low-mounted turbos is probably an easier (and certainly better) install than a front-of-engine single
Wednesday, April 18, 2007 - 08:59 pm, by: Sebastian Boyd(Wanted)
Dident think of that Ben, i know what your saying and i'l probably go that path, the reason i was thinking of going 2 small coolers is i'm also looking into some forged low compression pistons, rods and crank with some cams that can cope with some excessive boost
So i thought i'd try and keep as much air flow on the radiator as possible, but i can always make up for that with a new radiator and good quality oil cooler, what do you think?.
The longer the cores are, the more heat transfer there will be, thus better cooling properties and effieciency. Thats why the Height of an intercooler isnt the key, its the length of the flow. Well at least from mu understanding.
Sebastian, Sounds like a fun plan, but i hope you do realise the amounts of $$$ your going to need to do a project like that.
Brian Timms TryHard New South Wales TT Soarer Goodness.
Thursday, April 19, 2007 - 08:26 am, by: Brian Timms(Turbo_brian)
I remember someone ages ago on the Silvia Forums actually looked into the cooling surface area of a 700 X 450 X 45 intercooler, and found it to have close to the same contacting surface area (where air rushes across the surface of the cooler) as half of a football field, including 1 'in goal' area.
Something like 60 meters by 50 meters worth of surface area to cool with, which is pretty damn awesome!!
Anyways, a single turbo setup would be much more efficient (depending on the turbochargers used), and would also be much easier to set an intercooler to as well. Although I have seen twin input/oputput and twin input/single output intercoolers that would do the job nicely, such as the one pictured above.
Thursday, April 19, 2007 - 08:49 pm, by: Sebastian Boyd(Wanted)
Didn't think of it like that daniel your right, Even if i had 2 coolers i'd still only end up with 2 lots of medium warm air instead of cold air, But how much is a custom vertical cooler gonna cost me, any ideas?
Cant imagine a single turbo set up working on a uze-fe brian cause the exhaust's are on opposite sides of the engine bay, i'd have manifolds running all over the joint, still i don't know for sure maby u can?
A friend of mine actually found me some spec's on the water/air cooled intercooler shaun, there basically a lot more expensive and a lot more tricky and there also a lot smaller about the size of RB20DET intercooler, i had no idea how much more there is to it, its not funny so to save a few bucks and a sit load of head aches i'll stick with what i know a bit better i'll go air to air.
Roger Costello TryHard WA UZZ31 V8 Limited, UZZ32 no 867
Friday, April 20, 2007 - 08:56 am, by: Leon Wright(Techman)
Roger Costello wrote on Friday, April 20, 2007 - 03:16 am:
It has some real advantages and is not that hard to do.
My boss and I were discussing this setup not long ago, we really can't see how much gain you would get from placing the turbo at the back. I mean generally speaking you want the turbo as close to the engine as realistically possible as to improve spool and exhaust gas pressure. I suggest that any gains to be made by that turbo would be lost due to pressure losses coming from and going to the engine.
Friday, April 20, 2007 - 09:02 am, by: Leon Wright(Techman)
Looking closer at the pictures, the one we were looking whilst from the same company was a twin turbo setup. Also anything happens to that oil system say goodbye to your turbo/s!!
Duel inlet outlet Then you could run something similar to the picture you posted with the INtake in the middle of the engine facing forwards splitting off to either side!
You could work it just like this
Excuse my dodgy photoshopping,hehe! But you get the idea.
Brian Timms TryHard New South Wales TT Soarer Goodness.
It has some real advantages and is not that hard to do.
Has some real dis-advantages as well....
Oil Line failure (byebye turbocharger, and if not noticed quick enough, byebye engine)
Look where the Air filter is, no more dirt road shortcuts, no more driving in the wet, and constant replacement of filter (or wash of filter)
try to sneak over a small rise, byebye turbocharger (instead of slight nudge to diff)
Park on slightly long grass and see how long it takes to smoke the ground, or catch fire (turbochargers DO GET HOT)
Personally, a front mounted turbo is nice, and one of the best applications for a V configuration motor, gets the cool air from the front, cools down the turbocharger, but does warm the air as it passes, so the engine isn't getting as cooler air as you would like. But if this was a major concern due to heat of air in the engine bay, thing about the ambient air floating around 2 hot turbocharger units as they heat up on either side of the engine bay.
My choice would be a font mounted single turbo unit, or if it was completely custom, and the space was there, a rear mounted turbocharger unit.
The only issue with a front mounted unit that I dont like (coming from actually owning one in a FWD 4 cylinder) was the fact that you say byebye turbo in 90% of front impact accidents, as the radiator support moves, and hits the turbocharger almost every time, causing damage.
Friday, April 20, 2007 - 07:19 pm, by: Daniel Clarke(Dieseltrain)
WHy not Move the Battery to the boot. This clears one side of the engine bay. The Air box wont be needed, so there clears the other side!
With some Custom Radiator work and pipework, the Turbos could be mounted the same as the Pic Sebastian posted about.
I think thats the best setup. Plenty of engine bay room. But as mentioned, the extra heat inside the engine bay will be alot more if you dont HPC coat everything. Now you can clearly see why a supercharger kit is a good option.
Instead of the Turbo route, Have you thought about a Vortech T-Trim Supercharger and running something like this? Or even a Paxton Novi Blower? ONe of these with an air-air intercooler would reap some major horsepower with some Cams and the rest!
Much easier to setup and produce alot of HP. It seems you are not worried about low down grunt as with the TT V8 setup, there wont be much bottom end.
Saturday, April 21, 2007 - 09:20 am, by: Phil Gibson(Sciflyer)
The drag car boys like these rear-mount turbo setups as they are easy to install and they dont have to worry about ground clearance issues, dirt or lag
However despite the manufacturer claims they have poor efficiency and significant lag compared to conventional turbo installations which make them a poor choice for street or track cars (turbos require heat energy not just gas velocity for best efficiency)
Unless you want to run some insanely-sized turbo there is no reason why you couldnt do the job properly and mount it in or under the engine bay, even the LSx Holden/GM cars can make twin turbo installs fit this way and they dont exactly have acres of space- just like a V8 Soarer
"Running 14pound boost, and only revving to 5600rpm, the car made 527rwhp. Powerband is apparently fat as, with 490hp @ 4600rpm. To put it in perspective, the engine has been built to rev to 8500 all day long, and will be running 26psi on its track tune. Apparently they had a 25psi run, but it was just stretching all the tie-down straps. They were going to chain it down, but ran out of time. So yeah, looks very promising, 750rwhp looks to be a pretty realistic goal @25psi."
Saturday, April 21, 2007 - 03:23 pm, by: Sebastian Boyd(Wanted)
Lol, that rear mounted turbo is some thing, i'm with brian thou, the disadvantages seriously out weight the advantages and i think the claim to have full boost at 2000 rpm is a little optimistic.
Hey Daniel, yeah i've seen that one one ebay, it didn't even cross my mind that it could be used that way, i was thinking that i would still have to have both intakes on the same side, thanks a lot mate cheers,
Yeah there is no doubt i'll have to mount the battery in the rear, there won't be enough room otherwise.
That supra sounds great, apart from low compression forged pistons, what other engine internals would i have to change if any? Any educated guesses for what cams i would need to run (duration and lift) and what valve springs would be recommended ( kg rating) and any other advice on engine componets that i'v over looked, i know once you reach a certain engine power everything else needs doing up aswel but thats for another day, thanks for all your help guys.
Yeah i've thought of going the blower path Daniel, however i can't for two reasons, blowers make too much noise and i can hide turbos with heat shields and custom engine covers,
Saturday, April 21, 2007 - 06:10 pm, by: Daniel Clarke(Dieseltrain)
There are guys pushing around 600 hp @ the engine with stock 1uZ's and twin turbo setups.
It all comes down to the tuner....
Have you ever been in a 300rwkw car? COuld you handle driving it? The reason i ask, is your TT only ran high 14's ( i think from memory) for the 1/4 mile and your talking about pushing a Modded TT V8 to 25psi( which 15 will produce 500+hp anyways on a decent setup) and like 600+hp. This will be one fast ride. Basically not tractable on the street!
You could work with the stock cams for quite some time... You would be better off choosing the power figure your chasing, then the turbo sizes you are after. Cams will only be needed once your maxing out the setup.
Sunday, April 22, 2007 - 05:39 pm, by: Sebastian Boyd(Wanted)
Fair enough, i did some more tuneing to my car since then, managed to get an extra 38kw with just some diy mods costing pretty much nothing and a boost controller of ebay for 25$, don't know how fast it would be now, low 14's high 13's but i get your point.
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Then you could run something similar to the picture you posted with the INtake in the middle of the engine facing forwards splitting off to either side! 
