Low Profile Fan Shroud
#31
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Hans... the intake openings are an odd shape
1 9/16 ID at the inside arch, and 1 1/4 at the outside arch. the bottom is flat and the top slopes down with an progressive arch. The first half drops 1/16 inch and the second half drops 1/4 inch
1 9/16 ID at the inside arch, and 1 1/4 at the outside arch. the bottom is flat and the top slopes down with an progressive arch. The first half drops 1/16 inch and the second half drops 1/4 inch
#32
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I just pulled an S4 fan shroud out. The intakes, as Victor states, are not symmetrical. I did design a different version of the intake snouts which are symmetrical and as large as the S4 intakes, but they dont fit as well on the shroud. The S3 had a symmetrical opening, and think that is the way I am going to reduce the cost associated with molding the snouts (only one mold, and twice the volume to reach minimums.
For the initial batch, I don't think it will be practical to duplicate the S4 setup. I can easily lay out the openings for S4 snouts if someone else wants to commission the pair of intakes later on.
Oh, in case anyone was wondering, the area of the oval portion of the S4 radiator intake is way larger than that of the round outlet. On my smaller design, the oval still have over 500mm^3 more area than the outlet. Not sure exactly why the S4 inlet was designed that way.
For the initial batch, I don't think it will be practical to duplicate the S4 setup. I can easily lay out the openings for S4 snouts if someone else wants to commission the pair of intakes later on.
Oh, in case anyone was wondering, the area of the oval portion of the S4 radiator intake is way larger than that of the round outlet. On my smaller design, the oval still have over 500mm^3 more area than the outlet. Not sure exactly why the S4 inlet was designed that way.
#33
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Yay! I have been meaning to do this - now I don't have to. ![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
The only thing I might suggest is a vertical center divider/reinforcement?
This would stop the fans from flexing in and out and each fan would pull more strongly through its side of the core?
(Especially if only one fan is operating. By design or by malfunction.)
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The only thing I might suggest is a vertical center divider/reinforcement?
This would stop the fans from flexing in and out and each fan would pull more strongly through its side of the core?
(Especially if only one fan is operating. By design or by malfunction.)
#34
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Ken,
I was thinking about that the other day. I held off sending out the file to the fab shops as I was trying to see if I could match the S4 intake. By extending a small tab in where the flat of the fans are, I can have those bent forward to strengthen the center.
I am going to play around later to see if I can include mounting points for the Provent too.
Thanks
Hans
I was thinking about that the other day. I held off sending out the file to the fab shops as I was trying to see if I could match the S4 intake. By extending a small tab in where the flat of the fans are, I can have those bent forward to strengthen the center.
I am going to play around later to see if I can include mounting points for the Provent too.
Thanks
Hans
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Sagres74 (04-03-2021)
#37
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Was waiting to hear back form an interested party on a potential "universal" air intake which was slightly large than an S4 inlet, but symmetrical, so useable for both sides. I dont really like the part, its much larger than necessary, so think I am just going to go forward with the original units I designed.
I do plan on adding a stiffening rib to the center of the shroud. Will try and get than included this afternoon or tomorrow. I was hoping to 3D print one of the snouts, just to verify that everything lines up as intended, but I wont have access to our corporate printer for another week or so.
I will post the revised model tonight or tomorrow morning.
I do plan on adding a stiffening rib to the center of the shroud. Will try and get than included this afternoon or tomorrow. I was hoping to 3D print one of the snouts, just to verify that everything lines up as intended, but I wont have access to our corporate printer for another week or so.
I will post the revised model tonight or tomorrow morning.
#38
Race Car
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he said the sizing is really odd ball. Hans has one on hand so he has seen it. I'm down for having it be a tad bigger than s4 or s4 sized... i like my filters! i want to keep using them. thats my only issue at the moment
#40
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Its sitting on the launch pad till I get back from Third Coast.
My radiator started leaking, so going to take a core unit over with the drawings to a local shop I spoke to last winter about having radiators made (right before that last pallet of Behr units was located). Now that radiators are essentially NLA, I am going to see if I can get both made at the same shop.
I am going to print a pair of the intake snorkels to take over there next week to make sure everything fits the way I plan.
If anyone needs one of these shrouds sooner than latter, I would gladly work with them on an introductory price to help offset the initial tooling expense.
Thanks
Hans
My radiator started leaking, so going to take a core unit over with the drawings to a local shop I spoke to last winter about having radiators made (right before that last pallet of Behr units was located). Now that radiators are essentially NLA, I am going to see if I can get both made at the same shop.
I am going to print a pair of the intake snorkels to take over there next week to make sure everything fits the way I plan.
If anyone needs one of these shrouds sooner than latter, I would gladly work with them on an introductory price to help offset the initial tooling expense.
Thanks
Hans
#43
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I had to postpone my meeting with the radiator shop. Too much going on here at the office. I did want to get some pictures of the real snouts up though.
As you can see, they are slightly smaller than the original. These are closer in size to the S3 instead of the S4 snouts. I may make a second revision, with the inlets a bit wider, but as far as flow goes, they are more than sufficient.
You can see they mimic the stock trajectory very well, but unlike the stock part, they are "symmetrical" around the XY plane, making it ambidextrous and reducing the overall cost. It also is 3" (75mm) OD versus the stock 78mm which allows use of standard 3" flexible tubing.
I am still hoping to meet with the shop later this week, and will have a nice part to take them.
Thanks,
Hans
As you can see, they are slightly smaller than the original. These are closer in size to the S3 instead of the S4 snouts. I may make a second revision, with the inlets a bit wider, but as far as flow goes, they are more than sufficient.
You can see they mimic the stock trajectory very well, but unlike the stock part, they are "symmetrical" around the XY plane, making it ambidextrous and reducing the overall cost. It also is 3" (75mm) OD versus the stock 78mm which allows use of standard 3" flexible tubing.
I am still hoping to meet with the shop later this week, and will have a nice part to take them.
Thanks,
Hans
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Sagres74 (04-03-2021)
#45
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More progress on this project this weekend. I spent the better part of yesterday reverse modeling the factory 928 radiator. I now have a very accurate solid model of the original radiator (didnt bother adding the stiffening ribs on the tank). It is complete down to the sheet metal stiffening plates, and the additional hose holding trim plate. I am using it to tweak the shroud to the best possible fit/seal. I am also going to use it to shop around for an additional aftermarket radiator option.
As normal, attached are renderings and a 3D PDF.
Thanks
Hans
As normal, attached are renderings and a 3D PDF.
Thanks
Hans