#16
|
|||
|
|||
I think you are on to something
Hi, looks good. Since you don't have the engine in, can you mount it to a bare block and use a electric motor to turn the fan? With a electric motor driving the fan ,tape one on each side of very large trash bags and start the motor. See wich side fills first, most likely it will be the right side. Then you can talor your vanes. With the stopwatch and the same size air collector (trash bags) you can continue your R&D, you are on the right track and it can be done on a engine stand. Good ideal :agree:
|
#17
|
||||
|
||||
Quote:
Cool developments we all got going |
#18
|
||||
|
||||
Quote:
But I won't be working on one for a Type I engine, only Type IV. My preliminary design includes the use of the OEM 911 diverter as well as added airfoils and directional vanes to get the air where it belongs. Sandeep, While there is a documented 6HP loss from the Porsche set up, there is also a documented 23HP loss on the same dyno, with the same heads and cylinders and same drive ratio as the 6HP loss. Six HP is the absolute least i have ever seen with any 911 system- ever. Most are 15-18 or more. At dyno day I made 187 HP with the belt on with my 3 liter DTM cooled engine, when the belt was popped that went to 195HP- do the math and atleast 4 members of this forum witnessed the numbers. My DTM is driven just like any other, the stock TI drive ratio @ 1.58:1 Making a 911 system that cools all 4 cylinders equally and doesn't rob HP is possibly going to be the biggest challenge I have ever taken on yet. I really doubt I can beat the DTM, but from what I have seen if I even get it to cool evenly they will sell like a maniac just because of that damn look. Any system I work with will be set up to ustilize genuine Porsche alternator ring, fan and etc.
__________________
Jake Raby |
#19
|
||||
|
||||
Make a DTM with a fake 911 front
|
#20
|
|||
|
|||
The simple solution is make more power.
I really have a problem with accepting that a T1 fan is the best solution. If it were that good then Porsche would be using it too. A 911 fan has the cooling capacity to cool an engine with over 400bhp at the crank.Russ has been using his car for over 10 years with a 911 cooling system and obviously he's not the only one. Also worthy of note Russ uses a 5 blade fan for racing and the 11 blade for road use as the 5 wont cool the motor properly.Also the T4 heads seem to poorly manage the heat once you get in the 200bhp range the underside of the head seems to hold the heat in and distort the sealing surface. The 911 heads definately manage heat much better. My 2 cent fwiw Paul |
#21
|
||||
|
||||
Quote:
Quote:
I blew out a CV joint this week, have the parts to fix it, datalogger is installed ... looking forward to seeing some graphs. I'd be happy to share them. Quote:
I'm thinking in the early days of the T4 upright conversion, someone found out that the 911 fan was easy to adapt to a T4 for upright cooling, and designed a shroud just to get the engine in the bug and that was the main reason, not even cooling. With all of the tuners offering the 911 shroud, each seems to be a variation of that original theme, but trying to take cooling into account. Sandeep |
#22
|
||||
|
||||
911 shroud
This is what i am talking about, finally a 911 shroud that will work. Can someone post pictures of a diverter i want to check if i have the correct item.
|
#23
|
||||
|
||||
Quote:
BTW- It IS that good, ask Zen or email nosubt2@aol.com and ask him what his race engine (F prod 1800 TIV) did after removing the 911 shroud and opting for a DTM.. The DTM works well enough to keep my 3 liter cooler than a stock 2 liter and thats with 10:1 CR.... The dyno says it works and the satisfied users back it up.
__________________
Jake Raby |
#24
|
|||
|
|||
I'm thinking evolution here, the 356 had a bug style fan and the cammer had a different style ...why?
The Gol had an axial fan, at the end of play its about air flow and pressure. Ah I don't know why I'm posting this who am I trying to convince? BTW I think you'll find the cooling was designed for the engine, not vice versa. Last edited by BOBTAIL; April 27th 2005 at 07:21. |
#25
|
||||
|
||||
Quote:
However, the engineers had a lot of constraints they had to stay within. One obvious one that comes to mind (especially regarding fans and besides build-cost) could be the available 'space' on top, in front or whatever side of the engine. So, the best technical solution, is not always what has been produced... Greets, Walter Edit: The mail just brought a 993 head by today Nice design. I believe it has a 49mm intake valve and a 41mm intake port stock for a 100 mm bore Last edited by Wally; April 27th 2005 at 09:07. |
#26
|
||||
|
||||
The fan was designed for the engine and the engine designed to work with the fan as a unit...
Sit down and look closely at a 547/587, 616 engine and the 911... Then look at the TI and TIV and compare them all to each other. Compare the thickness of the fins on the cylinders and heads, their placement and even their length... I think Russ's 911 shroud works fine for what he does because the engine is more closely related to the 911 than a TIV or any other radial fan equipped engine. I would like to get some data from all 4 cylinders of russ' engine to see how they compare to what I have seen with the TIV head based engines and even what I have seen with my billet heads and the DTM. It might help shed some light on why some things occur. VW didn't spend the huge money on equipping the engines with Aluminum cylinders and etc so they had to create a coling fan that had a ton of potential. This was way cheaper than putting more into the money into the engine internals that would generate less heat.... Thats my hypothesis on why that fan works so well on the TIV, the added surface area gets the heat into the cooling ai stream faster and the high pressure air is forced in ever nook and cranny to get that cooling air stream more powerful and effective. In EVERY dyno test I ran my dyno cell ran hotter with DTM cooled engines than with any of the 911 systems, while the engines ran cooler... Proof that the air was being shed into the room at a much higher volume. These temps were as much as 30 degrees on the same day without variable weather between a DTM and two different 911 style shrouds... Just an ironic thing that we noticed while plotting every damn temp we could!
__________________
Jake Raby |
#27
|
||||
|
||||
911 fan and ring.
Hi Guy's
Can someone tell me if this is the original 911 turbo fan. The markings on it are 901 106 101 5r. Wally what ever happen to the photo of the diverter. |
#28
|
||||
|
||||
Ha, its still on my camera...
Be patient. I did some very rudimentary mods to it and in the shroud and also did some tests with those on the street. It will take some weeks maybe untill the film is full and gets developed and put on CD-rom... Greetings, Walter |
#29
|
||||
|
||||
911 shroud
Jake will your 911 shroud be a bolton.
|
#30
|
||||
|
||||
No, it will require machine work to fit under the decklid.
__________________
Jake Raby |
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
|
|