g60karmann 0 Posted September 4, 2008 does anyone else think this is a really bad idea? this is on an M5 producing 810bhp Quote Share this post Link to post Share on other sites
IansCorrado 0 Posted September 4, 2008 This seems to be the rage at the moment, seen loads of cars turbo charged this way. Not sure how well it works tho? Quote Share this post Link to post Share on other sites
g60karmann 0 Posted September 4, 2008 I would be worried about damage from cr@p on road or some chav tea leafing them! Quote Share this post Link to post Share on other sites
IansCorrado 0 Posted September 4, 2008 I see what you mean, probably not the best idea. Quote Share this post Link to post Share on other sites
plateletboy 0 Posted September 4, 2008 would the really long pipes under the car act like an intercooler with all that air whoosing past..?!?! pb Quote Share this post Link to post Share on other sites
Critical_Mass 10 Posted September 4, 2008 Wouldnt the turbos spool better closer to the front of the exhaust (source of hte exhaust)? Can someone explain? Quote Share this post Link to post Share on other sites
CrazyDave 0 Posted September 4, 2008 Looks like lag central to me! All that inlet pipe to fill with air when you open the throttle.... Not to mention that most of the exhaust gas velocity will have gone due to the drop in temperature out at the back. Obviously makes good power though, just wonder what it'd be like when you opened the throttle. Quote Share this post Link to post Share on other sites
herisites 0 Posted September 4, 2008 Looks like lag central to me! All that inlet pipe to fill with air when you open the throttle.... Not to mention that most of the exhaust gas velocity will have gone due to the drop in temperature out at the back. Obviously makes good power though, just wonder what it'd be like when you opened the throttle. My thoughts exactly! Not to mention throttle response being pretty sheeite! Also wouldnt want a small furry animal walking under the car after a spirited run, it would come out the other side as a fireball :shock: :lol: Quote Share this post Link to post Share on other sites
g60karmann 0 Posted September 4, 2008 the only advantage, and a very poor one at that, is the reduced heat in the engine bay and more importantly the throttle body(s) Quote Share this post Link to post Share on other sites
Trakx 0 Posted September 4, 2008 It seems a bad move. Lag will be exagerated by colder exaust gas and long distance from engine to turbo. Also, on the cold side, long intercooler pipes will also create lag and pressure drops. Road debris can be a problem. Also turbo oil feed lines will be big. Oil pressure drops could be a problem. Ball bearing turbos CAN NOT be used because the oil in this type of turbos go back to engine by gravitation (because of the total oil pressure drop in ball bearings). One final problem can be water cooling. One good thing about water cooled turbos is that when a hot engine is turned of, water flow will not stop because the water in the turbo will heat up and move upwards letting colder water in. Quote Share this post Link to post Share on other sites
VEEDUBBED 0 Posted September 4, 2008 The bugger still makes 810hp,even with remote turbos... Quote Share this post Link to post Share on other sites
CorradoVR6-Turbo 0 Posted September 4, 2008 just lazy..... Quote Share this post Link to post Share on other sites
mrbeige 0 Posted September 4, 2008 I was reading an article in PPC the other week, about a 205 turbo'd in this way and it goes against all normal turbo 'thinking'.....but, in the 205, there was next to zero turbo lag. The exhaust system will always be pressurised, so there is no need to build up the pressure in the system. Also the exhaust gases have cooled quite a lot by the time they reach the turbo, and thus they run more efficiently, and as the inducted charge goes from the the compressor back to the engine, underneath the car, the air passing by cools it on route and thus there is no need for an intercooler. Therefore no pressure drop there. Plus the air inducted into the turbo isn't going to be at under bonnet temperatures! Makes perfect sense to me. :D Quote Share this post Link to post Share on other sites
JoBlob 0 Posted September 4, 2008 Imagine those bad boys on a 1.0l corsa with 4 exhausts, thats got to make at least 1000bhp as that would be 4 chargers on each capable of 250bhp x 4 = 1000bhp, with the small turbos there would also be no lag at all, Veyron eat your heart out. Quote Share this post Link to post Share on other sites
CorradoVR6-Turbo 0 Posted September 5, 2008 umm...no lag,sorry but thats crap! Quote Share this post Link to post Share on other sites
mrbeige 0 Posted September 5, 2008 umm...no lag,sorry but thats crap! See, that's exactly what I thought when reading the article about he 205 in PPC, but if it wheel spins when going into 3rd, I'd think that that isn't the case. They did say there was next to no lag. Quote Share this post Link to post Share on other sites
boost monkey 0 Posted September 5, 2008 would the really long pipes under the car act like an intercooler with all that air whoosing past..?!?! pb yes, the air would help cool the pipes a little. Also, on the cold side, long intercooler pipes will also create lag and pressure drops. Thermodynamically, The pressure drops on a straight pipe are much much smaller than the pressure drops on bends. As a result, I would say the pressure drops in this 90% straight pipe system will be the same, if not less, than the pressure drops in an IC setup which twists and turns around the engine bay with a lot of 90 degree or gradient bends in it. Quote Share this post Link to post Share on other sites
g60karmann 0 Posted September 5, 2008 well in this set up you can see a fair few 90 degree bends just at the back of the system and then you have the turbulance caused by one turbo's outlet joining onto the others. I know they are both heat wrapped but having the inlet pipe follow along the exhaust can't be good for inlet temps. This M5 also has an intercooler, I think this example has been poorly done, but I have heard of good examples on other older BMW's. It all seems a bit mad to me and until I drive one I will stick by my thoughts that it is a bad set up. Quote Share this post Link to post Share on other sites
junkie 0 Posted September 5, 2008 Remember with the beemers there is most of the time feck all room to add the turbochargers, i have seen some with the turbo in the passenger footwell Quote Share this post Link to post Share on other sites
boost monkey 0 Posted September 5, 2008 Sounds like a toasty foot warmer for those winter blasts! :nuts: Quote Share this post Link to post Share on other sites
CorradoVR6-Turbo 0 Posted September 5, 2008 umm...no lag,sorry but thats crap! See, that's exactly what I thought when reading the article about he 205 in PPC, but if it wheel spins when going into 3rd, I'd think that that isn't the case. They did say there was next to no lag. sounds like he needs better traction... :lol: Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted September 8, 2008 A turbo imposes a huge restriction on exhaust flow where ever you put it, so mounting them at the back doesn't change anything. It's all about keeping the gas speed up, rather than temperature. Narrow bore exhaust and boost pipes do just that. Ball Bearing turbos can be used, and have been used in this configuration with scavenger pumps :-) You could even use variable pitch TDi turbos due to the lower temperatures involved and lag would be minimal. As for lag. You'd be surprised. The only way to settle the argument, scientifically, is with a compressor wheel speed sensor.... Quote Share this post Link to post Share on other sites
