I understand that the larger 80TB flows more air but I have my doubts about it's relevance, because the intake ports in the heads are really the restriction not the 75MM TB.

I can't find any dyno graphs from VRS, I will have to email him and see what he found. It could be he dosen't have the computer tuned to adjust for the extra incoming air.

 

Granted, the intakes are basically 50mm x 30mm (see photos) But lets play engineering students and say hypothetically that the SC creates a 7 psi increase over atmospheric pressure... And it runs at 12,000 rpm... And it has a 75mm hole to suck air from then cram it into a 50mm x 30mm hole... Do you think the volume of air moved through the 75mm hole would be the same as that through a 80mm hole ?

No, you would get approximately 269 ft3/min CFM more forced into the 50mm x 30mm hole... Now granted, you will have more back pressure created, but providing your SC maintains a constant 7psi, you will have an increase of air volume...

That being said, do you think I would rush out and buy a 5mm larger TB ? Absolutely NOT... I would first increase the intake and exhaust ports by 5mm and then increase the TB inlet to match...

FREE FLOWING COLD AIR is what we are looking for... And we all know that the REALLY SMART GERMAN ENGINEERS maximized this engine to balance performance, reliabiltiy and practicality... Not to mention CARB requirements...

 

Thanks for getting me into this air flow issue... I discovered a valuable bit of information that I will explain and follow-up with photos... Please don't diss me for my photos these days... I'm using my iphone as my camera... I'm lazy !!!

So we'll work backwards from the head upward and bare in mind i've had my Dremel Tool on some of this stuff... The intake at the head (block) is 50mm x 30mm and this meets the bottom of the flow through ports that are forged into the sides of the SC... The lower dimensions of these are 50mm x 30mm and the upper dimensions are 60mm x 32mm... These upper ports meet the intake plenum ports which are 58mm x 33mm... Then it moves up to the neck of the plenum box which squeezes to a 62mm x 40mm oval and into a 50mm round inlet... That inlet matches up to the 52mm outlet of the Y pipe that turns into a 85mm x 63mm oval... This mates-up with the outlet of the charge air cooler which is a 83mm x 64mm oval...

The intake of the Charge Air Cooler mates with the base of the SC which is basically a 140mm x 70mm rectangle.... The SC inlet is 75mm, exactly the same diameter of the TB...

 

HDDP,

You COULD go with the CM-90, it would have more than enough head to push your coolant around the car twice!

That would let you relocate the reservior/ice tank to the trunk if you wished. Just a thought.

 

Thanks Jody... You're right, the CM90 pushes 28 gal per min... But the inlet / outlet sizes are too large and also, I already bought the CM30 and designed the whole system around a 3/4" OD pipe...

 

Remember it's not about the GPM, but the pressure that the pump produces and works against. The CM90 has a much higher pressure than the CM30. Now, if you want something in between the CM30 and CM90... get the CO90... Supposed to move about 18GPM at 0.25 bar.

Marine pumps don't measure the 'head' like fountain pumps, but they measure the pressure at which they can pump a certain amount of fluid (same thing, different measurement units i.e. - meters/feet vs bar/psi). The pressure you have in your system will determine the GPM. i.e. - if you have a restriction that creates 0.2 bar of pressure... then your rate on the CM30 will be about 5.2GPM. Check the chart here. The CM90 is not on this chart, but you can figure it is above the CO90 as it's flow is higher at 0.25 bar.

Basically, if you keep the system fairly level, meaning the reservior/ice tank is the the same height or higher than the pump, then gravity works for you and the only real resistance you will have are the inlet/outlet sizes, intercooler and air charge cooler passages and a little bit of pressure to move the fluid to the top of the system (obviously less than 3 feet).

I realize that the whole system is in motion and there are variances, but you get my point.

Hope that helps... Cheers!

 

It helps alot... I just measured the water volume of the charge air cooler... it holds 0.195 gal. I'm building a mock-up of the ICE TANK as we speak which should be somewhere in the range of 2 gal. And with an estimated 8 ft of .60" ID tube that should contain about 0.11 gal. I think this should be adequate running alcohol & glycol as a coolant...

 

Don't forget the capacity of your intercooler in the front...

Glad to be of service sir... Keep us all in the loop, sorta speak.

Cheers!

 

Ah yes... Forgot that one... Won't be able to measure the volume till it arrives on the 14th.... Good deal... maybe I can make this tank a bit smaller...

 

Jody, since the writers strike sent most of Hollywood to the unemployment line, I had some time to mock-up the iced cooler tank today... Just to get an idea of how to build it and visualize the concept... I used foam core and lots of gaffers tape so it's not really pretty, but I'll post some photos later to let you see what I'm thinking and get your opinion before I start welding-up the aluminum...

 

Yeah, no worries... I'd probably keep it at around 2 gallons as the intercooler itself is not going to gain you but about an tenth of a gallon anyway. I would probably make it one gallon bigger myself, but you're probably trying to conserve weight.

I look foward to your design pictures.

 

This should make some sense if I explain it correctly... The tank is 14x8x8 which equates to a total volume of 3.88 gals... There are two seperate removable "FREEZE" chambers that fit inside the tank which are 8x6x2.5 which displace a volume of .53 gal. each, or 1.06 gal. Which makes the total capacity of the coolant tank 2.82 gallons...

The tank is "modular" in design... What I'm trying to say is that it's one primary tank that circulates the alcohol / ethylene glycol coolant and two seperate tanks that are filled with pre-frozen water in solid blocks and inserted into the primary tank... These secondary tanks are sealed from the primary tank...And I plan on having 6-8 of them built so I can swap them after each event...

This is hard to explain... Here's a photo explaination...

This is the tank system fully assembled

The left inlet hole will take the exhaust coolant from the "Bell Heat Exchanger"... and the right hole will pass the cooled liquid back to the OEM "Charge Air Cooler"...

The center cap is to fill the primary tank with the coolant... And the small white caps are to fill each "FREEZE" tank.

This is one "FREEZE" tank removed from the main tank...

 

This is a photo of both "FREEZE" tanks removed from the main coolant tank


I think you get the idea.... Each "FREEZE" tank fits inside the main coolant tank... The coolant is circulated past the "FREEZE" tanks and pumped back out to the "Charge Air Cooler", then recirculated back to the coolant tank where it is chilled again... I figure that the "FREEZE tanks will stay frozen for the entire length of an event, since they will be frozen solid...

 

Now the big problem is going to be welding this thing... I SUCK at TIG welding... and I don't want to have to farm this out to the metal fab shop I deal with... Especially since this stupid writers strike put me on un-employment...

 

just curious about why your using alcohol/ethylene glycol?

Distilled tap water is denser and has a better cooling effect than the ethylene glycol, and better heat transfer is the main goal behind all this work, correct?

 

Makes perfect since to me HDDP - pictures or not.

Have you decided exactly where to mount it?

Is your interior gutted? Or do you have to retain everything for your class?

SQ

 

One thing about your design... I'd probably suggest a full lip around the freeze tanks where they go into the main tank with 'ears' or something to lock them in place. The lip will give you a place to put a line of sealant to make a gasket on each freeze tank or on the main tank.

I'll see if I can whip something up to show you ... I hope you haven't started cutting the pieces yet...

Lastly... how thick is your material? 1/8 Inch? 1/4 Inch?

 

Here's what I had in mind. I tried to retain your internal dimensions on the tank.

Spacing of the tanks is off slightly and I forgot to include the filler and inlet/outlet ports.

 

HEY !!!! That's a really good addition to the design... If you don't mind me using it, I think I'll remove the bolts and put studs upward with wing nuts for quick / easy "freeze" tank changes... I have not bought the plate yet, but my idea was 3/16" for the "freeze" tanks and 3/8" for the coolant tank...

Now, learning how to TIG weld aluminum without LEAKS !!!

 

I was told that the ALC / GLYC mix would be the most efficient cooling liquid to use with ICE... I can only imagine that Gerhard Schruf would not be wrong, since he owns Bell Intercoolers...