what to do to get reliable 200hp?

[vanagonturbo]

hey now, I didnt mean to come across as attacking. I just wanted to point out what I have dealt with.

I would also point out that on the vanagon, the total capacity was around 3.5-4 gallons of coolant. The second revision got a 2.25 gallon res tank.

If you were closer, I could certainly arrange a ride and you can feel the intake manifold for yourself on the 1.8t rocco. If you are on Vortex, his username is Hybridvw. His name is Kelly. Really nice guy. And yes, ice cold intake manifold. No misting. Ambient air temp was around 70 degrees. It was on Grants Pass in Oregon around May.

I might also point out that all the air/water systems we have put in Vanagons are built by Bell Intercoolers if that helps you get an idea what we are dealing with. I would love to see cold charge pipes with an air/water but I just havent seen it yet without or the like.

[RabbitGTDguy]

Wow, sounds great. I'd love to do that...

On another note...part of the reason why I went with the air-water unit was the fact that I had the cooler already to go for the 'rado and never sold it off after building it. Also... with the mTDI project I wanted to do something different and I never liked having to find a huge amount of space on the mk1 for a large front mount air-air unit. My air-water unit allowed me to simply make a clean look to things be relocating the battery, optimizing the size and path of the intake track as well as kept me from cutting big holes, etc. etc. Not to mention...I have a whole "70 something" scene I'd like to obtain in the end and having the keg in the back of the car just makes it all that much more fun.

Not attacking...more contrasting.

Anyways...back to topic and I have to finish preparing the New Years feast of food and choice drinks!


Joe

[914turboford]

And yes, ice cold intake manifold. No misting. Ambient air temp was around 70 degrees.

And I thought I was the cheapskate. Why don't you guys get a non contact thermometer? They're on sale right now for $30 at Harbor Freight. Mine works really well. Then you won't have to argue ice cold vs. kinda cold vs. really cold. I hope I don't come across as rude. This is an interesting thread but I think it lost sight of its original purpose. OTOH, intercoolers are a very important part of making turbo power. On the A/A, is it FMIC or top mount?

[RabbitGTDguy]

And I thought I was the cheapskate. Why don't you guys get a non contact thermometer? They're on sale right now for $30 at Harbor Freight. Mine works really well. Then you won't have to argue ice cold vs. kinda cold vs. really cold. I hope I don't come across as rude. This is an interesting thread but I think it lost sight of its original purpose. OTOH, intercoolers are a very important part of making turbo power. On the A/A, is it FMIC or top mount?

Might have to do that...sounds like a hell of a deal! And yah...partly my fault, but it did get off topic...

Joe

[vanagonturbo]

My bad too. Sorry for the OT stuff. I actually plan on installing a temp sender on the IC on my rocco. I have put the factory MFA cluster in it but still need to wire the goodies in.

914turboford: all of the air/air speculation/testing (if you can call it that) is on FMIC. If you dont have room for an FMIC then go with the air/water. In my opinion, the SMIC is on par with the air/water setup for the most part.

Ok so lets get back to that 200hp formula.

Oh and have a happy new years all! Be safe out there, lotsa drunks. That reminds me that I need to put my rocco in the yard so it doesnt get smached bya  drunk.

[jtanguay]

interesting. I have to admit that my only experience with air/water intercoolers is on Vanagons. The first one we did had a fairly small radiator (about 20"x8"x1"). After driving the van on the freeway at a sustained speed of around 75MPH I checked the reservoir temp (1.5gal) and the intercooler. Both were almost hot to the touch. The pump was a VR6 aux water pump.

We decided that was unacceptable so we redesigned the core to about 36x42x2 and that helped a bit. Still had a warm intercooler and warm charge pipes post intecooler.

On my scirocco, I have an air/air unit. After getting off the freeway the post cooler charge pipe is cold to the touch. Same thing with the intake manifold. I have another friend with a 1.8t in his scirocco and after a good freeway run, his intake manifold was ICE cold.

I guess if most of your driving is around town an air/water might be ok. I just prefer to stick with what I have seen and know. Also on the point of water being able to absorb 4 times the amount of heat; although that may be correct, how long does it take to dissipate that heat? I would venture to guess it takes longer to cool off water than it does to cool off aluminum with air blowing through it.

Then there is also the consideration of weight. Water weighs quite a bit more than aluminum. I think I will stick with my 3 psi pressure drop and have a cold intake vs. adding an extra cooling system and having a warm intake.

i'm going to do it and use the newer style car sized radiators and use the thermoswitch from one to control the fan to cool it.  I will have cowling to make sure that air flows through the intercooler before the condensor/rad (yep... i want to try and keep a/c if possible :wink:).  the size alone of the radiator will really help cool the intake charge temps and the fan will also help keep the temps down in traffic.  IMO this setup would be FAR superior to any air/air setup.  true that once water is up to temp it does take more to cool it, but the size of the rad will help cool it off.

but enough with theory, i want to get it done already... just need to find the right air/water cooler first.  i liked the spearco ones.  the ebay ones look good but i'm not sure how efficient they are... one with very fine fins would be excellent.

[vanagonturbo]

We tried to fit the intercooler radiator in with the condenser and the engine radiator, but the intercooler radiator was too huge. We ended up mounting it under the van at an angle where the spare tire goes. It seemed to get plenty of air. I suppose if you use a smaller intercooler radiator or cut the body a bit you could get away with it.

[vanagonturbo]

good point. unfortunately, the guy REALLY wanted his AC so we couldnt mount it anywhere else. This was on the second setup btw. The first setup used a setrab cooler and it was small enough to fit in front of the condenser. that was also the one that got really warm.

it was also a syncro so there was plenty of room for flow. The guides that we put in probably helped a bit too.

[myke_w]

I know I'm out on a limb here, but all this ac talk and mention of an ice cold intake charge has me thinking.. has anyone ever tried to use ac refrigerant and a compressor to make a "refrigerant to air" intercooler, I know the power suck would be massive, and it's probably kind of complicated, but if the gains were great enough...?

Also, at what intake temp do you start to see a diminishing return, at what IAT does it become foolish to strive for a lower IAT yet?

[vanagonturbo]

IIRC Porsche uses the AC to cool the IC.

[91MF]

Ok so lets get back to that 200hp formula.

yes.

[RabbitGTDguy]

The idea of the use of AC as a cooling medium has been discussed before...i don't know if on these boards specifically but elsewhere (maybe TDIclub....def. the vortex...).

In the end do you think the power requirements/drag of the A/C system will really provide enough positives to offset the latter?

[RabbitGTDguy]

that would be interesting...

You first!

[vanagonturbo]

ok guys, we are acting like a bunch of ADHD kids. we have gone completely sideways from the OPs direction. I think we have almost dominated one entire page about intercoolers and still havent come up with what the OP wanted.

We all know that a mere intercooler on a TD will not net 200whp. so lets move on towards the other things.

I wish I had more to contribute. Big exhaust (2.5-3") would get you started. small intercooler piping will help too. I hear the best thing is to have the inlet piping for the IC a little bit smaller than the outlet piping. This will help accelerate the charge pressure through the IC.

[bigblockchev]

My sense of this is that the amount of heat that needs to be removed from the charge air going into the engine is quite significant. Any mechanical refrigeration system is not going to be able to cope with this. The only reason that  air to air intercooling works is that it rejects heat to the ambient air. There are  no mechanical  losses involved since there are no pumps or machinery present. With air to water intercooling there is at least a small pump involved but the heat absorbtion capacity is increased since water is capable of taking in much more heat than air is. With any mechanical refrigeration system there are pumps or compressors which have there own inherent mechanical inefficiencies. Absorbtion refrigeration systems use the density difference in the gasses & liquids to power the refrigeration cycle, so they have few moving parts but are not very powerful for their size. I'm generalizing somewhat but I am doubtful that anyone is going to get a refrigeration powered intercooler working anytime soon. I see the basics as
Air to air, good for continous  operation, should be large to be effective, should have exposure to free flow of cool air for best results. Simple.
Air to water  good for intermittant operation due to heat accumulation in the cooling medium. easier to fit into the engine compartment since it doesn't have to be as large as air to air. Should be a separate cooling circuit from the engine otherwise it will mostly transfer engine heat back into the charge air. more complex.
Refrigerant to air , other than Drag race style cool cans or ice packed intercoolers. Don't see how it could be done. Way too complex
Anyone else can jump in here with thoughts . Probably should be in it's own thread rather  than the 200Hp one.  Cheers Dan