|
|
|
#61
|
|||
|
|||
Quote:
|
#62
|
|||
|
|||
I know just enough to keep Brian and a couple of other guys stirred up ! LOL
MY impression is that as an example ... if you have air at temperature ' A' and ' B' is half way.... then you need the same amount of air 'C' ( plus whatever is needed to make up for the less than perfect heat transfer of the type metal in the tubes ) passing across the cooling part.... Which in itself can be a lot of air... meaning a drain electrically to run the fan.... |
#63
|
||||
|
||||
Instead of putting an intercooler inline with the radiator and fan, is there room for a top mounted intercooler with, dare I say it, a hood scoop to provide cooling air flow? You wouldn't need extra fan power, and sometimes it can be easier to fit an intercooler above or to the side of the engine. Then you can use a hood scoop, WRX style, or run a ram air hose up from under the car or something. I know hood scoops are awfully 'ricer', but I have no qualms with them as long as they are functional and not those fiberglass deals w/ double stick tape.
Just tossing the idea out there. peace, sam
__________________
"That f***in' biodiesel is makin' me hungry." 1982 300TD Astral Silver w/ 250k (BIO BNZ) 2001 Aprilia SR50 Corsa Red w/ 5.5k (>100 MPG) |
#64
|
|||
|
|||
Oh , Yes, Hood Scoops...
Why don't you start a new thread asking people's opinion of hood scoops.... You might be the first guy to be voted off the forum..... LOLOLOLOL |
#65
|
||||
|
||||
Quote:
Good lord I needed a laugh like that after trying to deal with my fuel flow problem......................
__________________
Proud owner of .... 1971 280SE W108 1979 300SD W116 1983 300D W123 1975 Ironhead Sportster chopper 1987 GMC 3/4 ton 4X4 Diesel 1989 Honda Civic (Heavily modified) --------------------- Section 609 MVAC Certified --------------------- "He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche |
#66
|
||||
|
||||
With all the added volume of air between the turbo and intake an intercooler setup would provide, wouldn't it also increase lag and move the power point?
Last edited by phantoms; 10-31-2004 at 07:39 PM. |
#67
|
||||
|
||||
Hey, hey, no need to get touchy. Boy this really is an old-folks board.
I was just trying to be practical. People were concerned about fan speeds needed to maintain airflow, so I suggested a practical alternative. If you don't like the idea, thats fine, I was just tossing it out. Even the McLaren SLR has intakes on the sides and hood (though the intercooler is cooled by that hood-star cum intake thingy, which is pretty sweet. However, if you want to totally smoke those kids in their rice cars, you really need these scoops: http://www.customautotrim.com/hood_scoops/ You don't even need to use screws to install them! OMG ThEY T0TALLY R0XoR!! peace, sam
__________________
"That f***in' biodiesel is makin' me hungry." 1982 300TD Astral Silver w/ 250k (BIO BNZ) 2001 Aprilia SR50 Corsa Red w/ 5.5k (>100 MPG) |
#68
|
|||
|
|||
Quote:
__________________
Tjohn 82 300 SD 77 450 SL (gone) |
#69
|
|||
|
|||
Wow, the post that won't die. Allow me to make a comparison. I know a little about GM 6.5liter turbodiesels. Like the MB 617 they are all cast iron, have a 21/1 compression ratio, are indirectly injected and non-intercooled in stock form. Stock 6.5's boost is set at 7psi. This is pretty low. The aftermarket and "tinkerers" have established that 12psi is pretty much the max boost recommended without an intercooler. This has been proven as the electronic 6.5's have IAT (inlet air temp) sensors that can be monitored while in service with a laptop and the correct software. It seems that anything more than 12psi and the IAT's increase sharply negating any benefit and causing the EGT's to quickly get out of line too. Since MB safety devices shut down fuel at 1.1bar or @14psi I suggest that the MB engineers knew of the sharp increases in IAT/EGT and choose to set the safety limits where they are. There are aftermarket intercooler kits for the GM 6.5's and the benefits have been documented with the laptop programs. On a stock 6.5 the IAT's can exceed 300*F when loaded and pulling. They can easily exceed 350*F on a modified 6.5 with more fuel and boost. Installing an intercooler on either stock or modified can reduce the IAT to within +30*to 40*F of ambient temps. The most popular is made by Spearco and fits between the framerails so I would guess it to be approx. 24"x8"x3" and it seems to cool a 6.5liters intake charge air just fine. The main benefit on a stock engine is reduced EGT's and heat load on the cooling system. The benefit on a modified engine is it allows the operator to stay on the accelerator when pulling a long hill, stay in a higher gear, etc. where before they would have had to back off the fuel due to high EGT's. It seems the intercooler doesn't neccessarily "make more power" it allows the engine to sustain maximum power for longer periods of time without damage thusly making more use of its power output. Regarding the ability of the MB transmission to withstand a power increase I would think 25 or even 50 more HP wouldn't really affect it in normal use. Normal use being the quick sprint 0-60mph, etc. and then just cruising around. Since with regular maintenence MB trans seem to last almost as well as the engines they would appear fairly robust. For a truly max effort hotrod MB engine an experience transmission rebuilder would know how to increase the line pressure to increase the clamping pressure on the clutch packs to keep them from slipping and get the power to the ground. There are custom injector builders around. I doubt they have ever worked on MB injectors but since they have modded just about every other type of diesel injector for the pulling/marine/hotrod crowd I am willing to bet they could do a set of high pop/high volume MB injectors if you were willing to pay. Regarding fitting an intercooler into a 123/126 chassis I think it would be fairly simple. The easiest way would be to do away with the AC condensor and mount it there. Another would be to convert to an electric fan and move the radiator/condensor back towards the engine to make room. Sure, custom mounts and fabrication but within the realm of possibility. I still don't think there is much of a market for a 617 intercooler. There really isn't a reason and no one seems to want to spend the money. Interesting topic though. I wish Ridge had followed through with the before/after tests to see if his intercooler worked or not. RT
__________________
When all else fails, vote from the rooftops! 84' Mercedes Benz 300D Anthracite/black, 171K 03' Volkswagen Jetta TDI blue/black, 93K 93' Chevrolet C2500HD ExCab 6.5TD, Two-tone blue, 252K |
#70
|
||||
|
||||
If someone could actually prove it accomplishes something I'd be willing to build up a intercooled system but I'd rather build my own system than buy it.
Spearco makes very nice intercoolers but their prices are a little out of hand in this situation, I'd either use a Starion or DSM intercooler in this case. I'd probably go with DSM intercooler as I have access to cheap ones and they are a very efficient intercooler. Injectors can be extrude honed if the money is right, but before I'd consider sinking much into this car I'd probably get something else much more modifiable (Dodge Ram w/Cummins? ). All I can figure is Subaru's marketing team must have forced their engineers to have a top mount intercooler. It just doesn't make sense why someone would do that, heat rises and they put it right above the motor. One of the first mods for a WRX is to rid of the top mount intercooler. The current tranny may put the power down but will they last? The 603 will put put out a good deal more power than the 617 but most of their tranny's seem to fail every 100-200k miles as well. Yes the intercooler would create a little extra turbo lag as it is that much more volume it'd have to pressurize before it could reach the engine. I'd be much more concerned with the effect that driving in the winter with a intercooler than this issue though.
__________________
Jeff M. Mercedes W123 DIY pages are now located here. 1983 / 1984 300D Sold 2000 CLK430 Cabriolet ~58k Sold 2005 Avalanche 4x4 ~66k |
#71
|
||||
|
||||
the key to minimising turbo lag is keeping the path as short as possible. Hell these things are no speed demon and I doubt a litle turbo lag would even be noticed. Reducing charge temps is a good thing. would even let you tweek a bit more fuel through it safely. However those of us with a W116 chassis are at an even greater disadvantage as we have a battery up front behind the RF headlight. Without going to a electric fan to allow spacing the rad back to allow a intercooler between the A/C condensor and radiator I can't figure how to make one fit. I won't give up A/C for it. And I have looked, and looked, and still haven't figured out a way to make it work any other way.
__________________
Proud owner of .... 1971 280SE W108 1979 300SD W116 1983 300D W123 1975 Ironhead Sportster chopper 1987 GMC 3/4 ton 4X4 Diesel 1989 Honda Civic (Heavily modified) --------------------- Section 609 MVAC Certified --------------------- "He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche |
#72
|
||||
|
||||
Not sure if anyone's mentioned it before, but an air to water intercooler is also an option for tight installations. Some of these units are fairly compact, which allows for shorter lengths of turbo plumbing. The heat exchanger can be mounted somewhat remotely, but this typically requires an electric cooling fan, so the increased power and efficiency isn't exactly "free".
Also for the more adventurous race-types, these ATW intercoolers can be loaded with icewater that under certain conditions, can introduce charge air that's actually below ambient temps. |
#73
|
|||
|
|||
Quote:
|
#74
|
|||
|
|||
Quote:
|
#75
|
||||
|
||||
Well I guess since this is somewhat applicable here, Brian has said many times that he wanted to get a better exhaust system for his car. I heard from several people here that the difference between no exhaust and the stock is very small. Well the other day I ran into a guy who owns a shop that services MBs in alabama, he is Bosch certified. He was telling me how he could tune the 617 so it'd put rubber down in two gears, he mentioned that changing the exhaust will actually make a noticeable difference in power.
__________________
Jeff M. Mercedes W123 DIY pages are now located here. 1983 / 1984 300D Sold 2000 CLK430 Cabriolet ~58k Sold 2005 Avalanche 4x4 ~66k |
Bookmarks |
Thread Tools | |
Display Modes | |
|
|