Custom fan Shroud .

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bj
Posts: 1156
Joined: Sat Feb 08, 2003 12:01 am

Re: Custom fan Shroud .

Post by bj »

when are you going to sell these ;-)

looking forward to seeing your progress...the CHTs look VERY promising!

Happy Holidays!

BJ
wreck
Posts: 490
Joined: Thu Aug 14, 2014 12:07 am

Re: Custom fan Shroud .

Post by wreck »

Hi BJ

I may produce a few kits but it won't be for a while ,maybe later part of next year. I'm really time poor at the moment and am making plugs and moulds for a single airbox filter system plus setting up a Megajolt ignition, fitting AC and a serpentine belt system .

I've been driving the car daily and am happy with how cool the temps run , #1 runs the hottest at an average of 120C ,#2 is the coolest at 105C .(the thermocouple is bonded to the plug boss so the readings are slightly lower than under the plug ). #1 stub pipe has a larger dent in it to clear the pushrod tubes . I wonder if it is causing the higher CHT . I'll straighten out the pipe(to match #4) early next year when I get the whole system ceramic coated .
Also the 48 Dells have a hole in the butterfly and I'm finding the idle mixture screws are very vague but adjusting them make a big difference to the CHT .so I'm going to block up the holes and see what that does .

For oil cooling I've 2 coolers either side of the gearbox with properly shrouded fans with a Mocal sandwich thermostat . the oil temps rises up to 90C then the fans kit in and regulate the temp straight back at an average 80C or so . All this in humid 30C ambient temps .

I wonder how many big bore/stroke high comp type 1's run that cool :-) . I'll try and get a video up in the next week or so of the gauges/temps etc .
No matter where you go , there you are !
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bj
Posts: 1156
Joined: Sat Feb 08, 2003 12:01 am

Re: Custom fan Shroud .

Post by bj »

wreck wrote: Fri Dec 22, 2017 12:43 am Hi BJ

I may produce a few kits but it won't be for a while ,maybe later part of next year. I'm really time poor at the moment and am making plugs and moulds for a single airbox filter system plus setting up a Megajolt ignition, fitting AC and a serpentine belt system .

I've been driving the car daily and am happy with how cool the temps run , #1 runs the hottest at an average of 120C ,#2 is the coolest at 105C .(the thermocouple is bonded to the plug boss so the readings are slightly lower than under the plug ). #1 stub pipe has a larger dent in it to clear the pushrod tubes . I wonder if it is causing the higher CHT . I'll straighten out the pipe(to match #4) early next year when I get the whole system ceramic coated .
Also the 48 Dells have a hole in the butterfly and I'm finding the idle mixture screws are very vague but adjusting them make a big difference to the CHT .so I'm going to block up the holes and see what that does .

For oil cooling I've 2 coolers either side of the gearbox with properly shrouded fans with a Mocal sandwich thermostat . the oil temps rises up to 90C then the fans kit in and regulate the temp straight back at an average 80C or so . All this in humid 30C ambient temps .

I wonder how many big bore/stroke high comp type 1's run that cool :-) . I'll try and get a video up in the next week or so of the gauges/temps etc .
trust me...i understand "time poor" for sure! keep plugging away!! my car has been sitting for 10 years. i've been working on it that long! soon though..soon...

thanks for the info and the innovation!

BJ
wreck
Posts: 490
Joined: Thu Aug 14, 2014 12:07 am

Re: Custom fan Shroud .

Post by wreck »

Still trying to get the head temps more even on the right side , about 15C lower on #2 , #1 and #4 are dead even and #3 about 5C hotter . I think it's related to the shroud shape favouring the colder cylinders so next step is to modify the shroud . Running with the belt off the temps are even so I know my CHT readings are accurate and the engine has no issues . cranking compression of 130psi on all four .(310 degree cam)

I went for a 50k drive on a +35C humid day 2 weeks ago and the CHT's only reached 135C in stop start traffic and stabilised at 120C at 3500rpm in top gear at 100km/h . that was running a lower fan drive ratio than standard (same as a power pulley) . So very happy with that .
No matter where you go , there you are !
E_bug
Posts: 260
Joined: Mon Dec 28, 2009 11:05 pm

Re: Custom fan Shroud .

Post by E_bug »

Very nice build ! I like the oil squirter setup.
My welding sucks .
Mave
Posts: 33
Joined: Thu Jul 18, 2013 11:25 am

Re: Custom fan Shroud .

Post by Mave »

Looking great so far. Are there any updates on the shroud design? Would also love to see your take on the airbox design!

Marcel
wreck
Posts: 490
Joined: Thu Aug 14, 2014 12:07 am

Re: Custom fan Shroud .

Post by wreck »

air box 1.jpg
airbox 2.jpg
I spent a long time trying to get an air box to flow enough ,the engine is making about 170 whp , it would get restricted over 1/2 throttle . I doubled the air filter panel size but still no good .

The shroud needs a little tweeting on the #1 #2 side , they run about 15C apart , #3 #4 run within 5C of each other . On a 30C day the CHT on cruze at 3400rpm is 110c to 125C across the 4 cylinders . measured at the spark plug boss .(thermocouple is JB welded to the head) that is with standard Type 1 fan ratio .
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No matter where you go , there you are !
H2OSB

Re: Custom fan Shroud .

Post by H2OSB »

Love the airbox! I want one of those very much...eventually.

H2OSB
Mave
Posts: 33
Joined: Thu Jul 18, 2013 11:25 am

Re: Custom fan Shroud .

Post by Mave »

Nice. Great to see how you make these yourself, and are working on improving their functionality. Keep us updated!

Marcel
Steve Arndt
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Joined: Sat Mar 10, 2001 12:01 am

Re: Custom fan Shroud .

Post by Steve Arndt »

Bump. Very cool thread. Can't believe I hadn't seen it before. I have all the parts to build a 78x103 (been collecting parts since 2001. Six studded 48x40 heads from Power Tuning, BAS 21158 1 3/4" merged header, Porsche squirters, lots of trick parts.
wreck
Posts: 490
Joined: Thu Aug 14, 2014 12:07 am

Re: Custom fan Shroud .

Post by wreck »

Thanks Steve , with all the work involved with the piston squirters I found don't need them . The engine runs cool . typical CHT's are 110C pretty much regardless of ambient . I'll hook up the head spray bars more for better valve/guide /spring life . I'm already running a very low pulley ratio on the fan . Once I have the revised shroud completed ( couple of weeks) I'll do an update .
No matter where you go , there you are !
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V8Nate
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Joined: Mon Sep 03, 2018 12:34 pm

Re: Custom fan Shroud .

Post by V8Nate »

Excellent work and R+D!
subtaf
Posts: 70
Joined: Wed Jun 24, 2009 5:53 am

Re: Custom fan Shroud .

Post by subtaf »

As I read through this I keep asking myself over and over, why, why didn't VW think of this?? It makes so much sense IMO. Is it to do with the fact they would've been trying to make this frim sheet metal?
dragvw2180
Posts: 287
Joined: Mon Jul 17, 2006 12:01 pm

Re: Custom fan Shroud .

Post by dragvw2180 »

Your air inlet system looks very much like my 69 911 had , it seemed to work pretty good .
Ol'fogasaurus
Posts: 17758
Joined: Mon Nov 13, 2006 10:17 pm

Re: Custom fan Shroud .

Post by Ol'fogasaurus »

subtaf wrote: Sat Jun 15, 2019 11:53 pm As I read through this I keep asking myself over and over, why, why didn't VW think of this?? It makes so much sense IMO. Is it to do with the fact they would've been trying to make this frim sheet metal?
Something like that would be fairly easy to make flat patterns for then be bent up (probably stamped) in "Tin" but it would be in at least two pieces; a top and bottom. Then you have to consider just how much time there would be a lot of time spent developing the flow patterns in the windtunnel :wink: :lol: . The standards they had/have to meet are much more involved than what we do as individual car owners :lol: .

The other thing is we are not using the "bug" as it was origionally intended; what they developed back in the '30s and after WWII, to use on the Autobaun and plain 'ol city streets is/was probably more than satisfactory.

Things are often much more complicated for businesses than private citizens usually thinks there is (unless we have a problem and are irkked about it.

Lee
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