Buellwinkle

I have the results back from my intercooler testing. The Renntech was tested in an automatic coupe (max rpm 5,915) vs. the Racetec on my coupe which is a manual (max rpm 6,224). Since my coupe can rev higher it does introduce more heat to the intercooler because of the higher boost level. The runs were done back to back, same stretch of road and both around noon at 75F degrees as measured on the car's display. Both cars had the same ASP alloy pulley with steel hub.

Renntech
1st run, 90mph 102F at 3998 rpm
2nd run, 88mph 115F at 5805 rpm
3rd run, 85mph 118F 5635 at rpm

Racetec
1st run, 80mph 102F at 6214 rpm
2nd run, 80mph 108F at 6148 rpm
3rd run, 92mph 120F at 5044 rpm
4th run, 94mph 118F at 5259 rpm

Boost pressure measured -
Renntech 9.1 PSI
Racetec 10.0 PSI

gab

what about ambient temparture?
how much time is allowed to cool down between runs?
what aboutpsi drop across each intercooler?

Buellwinkle

Ambient was 75F for both sets of runs, I accellerated from 0 to about 80 back to back with no wait, maybe 2-3 seconds at most. Renntech showed a .7 PSI drop, Racetech showed no drop in pressure.

hokusbenz

so does this mean the racetec is better then the renntech? or no

Buellwinkle

Cooling effect appears to be equal on both units. The key is the pressure drop. The goal in any intercooler design is to cool effectively with minimal pressure drop. I feel the Renntech loses boost pressure because of the end tanks design and an intercooler that may be too big for it's application. Don't confuse that with air volume as that remains the same between the different intercoolers as the air from the s/c has to go somewhere. But boost pressure is what makes power and the Renntech will lose power, mostly in the mid range. Typically any intercooler will lose 1-2 PSI of boost pressure, even the factory one. The goal is to have a smooth design to minimize this pressure loss. To minimize this pressure loss Racetec starts with a German made core that's very effecient, then they make the sides of their end tanks evenly slant towards the pipe with no welds in the corners where pressure is highest. Also the elbow is a smooth 90 degree bend.

BTW, after I was done with the intercooler testing I got my intercooler sprayer working using factory parts for the headlamp washer (pump, wiring and switch) and it works well and is virtually plug and play. Because I switched back to the factory pulley after the testing above I wasn't able to get test results with the sprayer. My goal is to drop the 120F max down to below 100F and automate it with the Labtronics controller.

taylor192

Buel,

You will have to explain your intercooler sprayer steup a bit more, or maybe take some pics, but are you just basically spraying it with washer fluid? or do I understand correctly and you actually bought a second pump and basically mimiced the exisiting setup?

Buellwinkle

I bought an MB pump that fits next to the windshield washer pump in the slot for what would have been the headlamp washer pump, plugged it into the harness provided, got a headlight switch that includes the headlamp washer button and walla, instant sprayer. Then of course I ran tubing, check valves, strainers and spray heads to the front of the intercooler. And yes, I took the soap suds out and put in distilled water. The next step is to disconnect the heating element in the washer tank, don't want to spray hot water on the intercooler. For people in cold climates this may be done in the way of a bypass valve that they can turn on in winter and off in summer.

This is just phase 1. Phase 2 is automation, have the spray come on automatically when core temps exceed ambient by about 20F degrees and engine is under load. The other reason for automation is that it's a lot cheaper than getting that correct headlamp washer switch. The current setup I have would cost you about $350 to replicate, not cost effective but makes for fun testing.

taylor192

Sounds good, but why not try and fish around from some extra room and install a second reservoir? That way you could keep the washer fluid and not be forced to use water (which those of us up north could never use.

Sounds like it will work, except if you do automate it, you will need a mechanism to disable it when the water tank hits a low mark, or tap the exisiting sensor, but if you did and the sensor ever failed, that MB would surely screw you for it.

OK, I don't know much about this topic, but isn't their aftermarket nitrous sprayer kits available that would probably run less than your experimenting? and probably work better?

Buellwinkle

You find a water tank and pump that will fit anywhere and let me know, I've tried, even search salvage yards for the right setup but there isn't a convenient place to mount this that I could see. There are small nooks and crannies but nothing big enough. As for NO2 sprayers, that would work well and so will the CO2 kits out there, how much does it cost to fill up an NO2 or CO2 tank? Where do you get it? How do you know when that tank is empty? Where do you put the NO2/CO2 tank? I know I can get distilled water pretty cheap and in lots of places. Also is the nitrous automated for that price they ask or is it push button? How do you know when to push the button? Do you then have to have an intake air temp gauge to tell when to push the button?

I'm not trying to be argumentative, if you know a better way let us all know, don't want to head in the wrong direction. But if you have a better way, please give specific details.

My guess is that I can do a fully automated system for about $159 including electronics, check valve, strainer, pump, misting nozzle, tubing and wire. In comparison, the Aquamist system is about $500 not including the tank (as they expect you to use the windshield washer reservoir).

speedfrk

When it is cold enough outside to freeze water, you don't need an intercooler sprayer. Just disable it for the winter and put regular washer fluid in. You only need the sprayer for very hot conditions or racing. Also, nitrous is way more expensive than water.

taylor192

No need to get defensive, just wondering why you went one direction and not another. Yes nitrous is expensive to refill, but it does solve 1 problem you will have: automating the shutoff of the system when you run out of coolant.

You mentioned before that you were at $350, not $159, and that's why I mentioned the alternative as you were getting up there in price.

Now where to mount an additional tank... there's gotta be room under the hood somewhere...

As for the automation, that should be very simple with some of the programmable boards out there for simple robotics control. I'm betting the coolant low signal is an on/off voltage level, and can be fed directly into an interrupt line for a microcontroller.

Buellwinkle

I said with the setup I have it's about $350, mostly because the headlamp washer switch is $236 by itself, that's why I'm looking into automation and already have a controller board to do this. If we use the windshield washer reservoir that has a pretty good warning system that triggers way before it's truly empty. Besides, what would it matter if the system went dry, you would just lose a little performance until you filled up.

So besides comments like it's got to fit somewhere, open your hood and tell me where you can hang a 10 pound object that has easy refill access and minimizes heat absorption from the engine. I know one place, behind the passenger headlight but you'll need a custom made reservoir with a long neck similar to the factory reservoir. But the tooling costs for the quantity required is prohibitive, it would have to be a part already in production. Like someone said before, this is a summer time need for most people, a valve that disables the heater in the windshield washer reservoir is more than adequate. Throw in a couple of ice cubes on track day and you're set.

Blaxer

Hey Buell thanks so much for all the info, I know that I appreciate your being a "guinea pig" for the rest of us :-D . I am very interested in this upgrade for my 03' car. Am I correct in assuming since it will bolt on the 02' the same is true for the 03' car?


TIA
Blax.

Buellwinkle

From what I've been told it will fit '03 as they are the same MB part number.

Blaxer

Thnx much!

taylor192

Ummm not that simple as far as I understand it, maybe the MB water pump is different, but if you run them dry you're in danger of damaging them.

That's an incredible amount for a switch.

Buellwinkle

Exactly, that's why the way to go is with the windshield washer reservoir, early warning.

It's a very complex switch with 14 wires going to it. It controls your mirrors, headlight and headlamp washer button.

tifosiv122

Just testdrove the Evo8 which has an auto and manual spray for the 'cooler. You might want to check out the system for ideas and whatnot.

Erik

Outland

Spraying Nitrous OUTSIDE the intercooler is a waste. Spraying nitrous in the intake stream will cool the intake charge more than the chilled intercooler, and you'll even get the added HP from the NO2 at the same time.

tifosiv122

No you won't...the amount of n02 sprayed and the fact that it will dissipate before reaching the engine. This is why you can use Carbon Dioxide as a substitute...you wouldn't spray that directly into the engine.

Erik