The ongoing saga of turbo woes finally seems to be nearing the end. The latest development relates to cooling. While at PIR in September and again at Pacific Raceways in October, my EMS data logs indicated that my car was running over 225 degrees F -- perhaps as high as 228 degrees (we've had to develop our own temperature calibration table for the EMS b/c the table contained in the base maps wasn't correct). Because I've got the Mugen radiator cap (as well as the thermostat and thermo-fan switch) I didn't suffer any boilovers, but clearly my operating temperatures were higher than is desirable. In addition, others -- thanks to DavePK (S/C) and Yellowstreak (now NA) for sharing their observations -- have discovered after mounting an oil temperature gauge that the oil temperatures while on the track are very, very high, on the order of 280-290 degrees F.

To resolve these problems, GilbertG and I are having C&R Radiators design a custom, thicker (56mm) core radiator with (i) a single very high capacity fan (2360 cfm -- about three times the combined capacity of the stock fans) and (ii) an integrated oil-cooler (where the coolant flows through half the radiator and is used to cool the oil before cycling through the other half of the radiator). The design allows the unit to be mounted using the stock mounts and should accommodate the existing hoses, thermofan switch, intercooler piping (providing your intercooler uses the Speedcraft/Stage 6 design), and coolant overflow tanks with only minor changes in the plumbing. C&R is making this for us for $1100 plus s/h. The radiator-oil cooler should be finished in time for my next track date in early February at Laguna-Seca, which will give me the opportunity to see how well it works under track conditions. (Thanks, UL, for your advice during the early design stages of this project last fall.)

In addition, I'm intending to:

1. Run an oil line from the block (where the stock oil pressure sending unit was originally mounted) to the strut tower brace in order to relocate the oil pressure sending unit and the oil feed line to the turbo. The purpose of this is to relieve the strain of hanging a t-fitting off the block for these two devices. (Thanks to Vapors2k, XViper, and DavePK for this suggestion.)

2. Buy the GReddy oil drain bolt adapter and mount an oil temperature probe in the pan and wire this to the EMS (without mounting another gauge on my dash). (Thanks CJB80.)

3. Install an oil pressure sensor in either one of the ports for the oil filter relocation kit or in an in-line fitting located in the return line from the oil cooler.

In combination, these changes should resolve my coolant and oil temperature issues and allow me to log my oil temperature and pressure.

The purpose of this post is to (i) solicit any final advice before we do this thing and (ii) let others know about C&R Radiators. I've been very, very happy with the support we've gotten from them. We've worked with Kevin van Cleef, who's been extremely helpful -- he's a former Honda mechanic (5 years) before joining C&R and he clearly knows his stuff. Moreover, he's really bent over backwards during the design to insure we're getting a product that will fit and we'll be happy with. C&R can be reached at 317-293-4100. Their website is http://crracing.com. I wanted to share our very positive experience with the boards in case anyone else is grappling with these issues. For those of you who only want to upgrade from the stock setup, C&R makes a drop-in slightly thicker-core radiator for the S2000 that's worth consideration (it's cheaper than the Mugen product and I have no doubt that it's of comparable or better quality). They can also use our setup to custom fabricate a radiator for you, with or without an integrated oil cooler.

Pls. post if you've any final suggestions on all this, and I'd be happy to talk more about our experiences with C&R for anyone who's interested. They've been great.

Best,
CB

_________________
C. Bender
2001 Silver/Black
AEM EMS, Fuel Pressure Regulator, and Wideband O2 Sensor; RC Engineering 550 Injectors; Turbonetics TO4B 60:1 Ball Bearing Turbo; Tial 46mm Wastegate and 50mm Blowoff Valve; GReddy EGT and Boost Warning Gauges; Holly 250 Forced Induction Fuel Pump; Oil Filter Relocation Kit with Stainless Steel Lines; Speedcraft Front Mounted Intercooler, Mandrel Bent Tubing, 3" Down Pipe, and 3" Stainless Exhaust; A'PEXi N1 Mufflers; Clutchmaster Stage 3 Clutch; Toda Lightweight Flywheel; Mugen Radiator Cap, Thermostat, and Fan Switch; Upgraded Oil Bolts; Spoon X-Brace; HeCash Brake Ducting; Competch Stainless Steel Brake Lines; WorkMeister S2R 18" Wheels; Lucid's Front and Rear Speakers; 2002 Stereo Head Unit; Rick's Front Badge; JDM Clear Side Markers and Shaved Badges; Muz Shift Knob; Uber Cool Nurburgring Decal

 

Have you thought of changing the coolant temperature sensor for one which reliable calibration figures are available for the EMS, before you change the radiator? I'm just thinking that you'd be able to compare figures under low load on the road to what you've seen with the questionable calibration with the stock sensor. I'm only curious to see how accurate the coolant temps you've logged to date are. I don't have an oil temp gauge on my car yet (keep meaning to get round to it...), so by knowing the coolant and oil temps where things are getting marginal, would give an idea of what the difference between coolant and oil temps is under those kind of circumstances. Just curious

-Brian.

 

thanks for the info cbender
keep us posted of your result on track

have you got any pics yet? could you kindly post 'em?

[QUOTE]Originally posted by cbender
2.

 

Brian: it's a good thought, and it certainly makes sense to first get good data and then make changes using that data as a baseline. That said, I'm completely certain that I'm running way too hot -- even with very aggressive fan settings on the EMS and the Mugen cooling mods -- because GilbertG actually measured his coolant temperatures and compared them to the sensor voltage readings in order to develop his own table for the EMS. Using these values, I'm still running well over 220 degrees on the track.

Honda9k: no photos, as the unit's still being built. Thanks for the tip about the VDO. I'm planning on using the drain plug adapter b/c there seems to be some consensus that it's desirable to measure oil temperature in the pan, rather than elsewhere.

CB

 

Are these high temps you are seeing the peak numbers recorded or some sort of average?

I use a CarChip when I go to the track and can log the coolant temp every five seconds. I have seen that it peaks at the end of the straight but drops immediately so that if varies about 7 or 8 degrees every lap. It is interesting to see on the straights the IAT drops and the ECT rises, and then it reverses in the back of the course.

I don't know how accurate the numbers from the ECU are but with the ambient of 65F I never see ECT over 189F (using the Mugen cooling mods) and in 95F ambient it still stays below a 203F peak most of the time.

Have been assuming that oil temp is running about 40-50F higher so I have not worried about more cooling for my sometimes track car.

With measurements being take in different places with different equipment we have a wide range of temp reports. Clearly some track cars (especially with FI) have needed extra cooling, but I am still not convinced there is a need for most with light track use.

It will be good to see the results from your serious endeavor to run cooler.

 

Hi CDelena,

Nice to hear from you.

These are peak numbers, as reported by the EMS using the inputs from the stock coolant sensor. Under very hard driving on the track -- when I'm at full boost coming out of most of the corners and the entire way down the next straight -- my temperatures aren't changing dramatically across a lap. That's clear from my EMS logs.

It's true that nobody really knows what to make of the EMS-reported temperatures -- my voltage calibration table is based on empirical measurements that GilbertG did with his car -- but it's clear that I'm running hotter than one would like. My oil, after one track day, is thin and black, which is probably a good indication that it's also getting too hot.

I'm convinced that I need this, but you may be right that it's not necessary for most people (although an oil cooler might be necessary for anyone tracking their car hard). In any case, my purpose in posting this thread was to solicit suggestions for finalizing the design and to also give some credit to C&R in case others are thinking they need cooling mods.

Best,
CB

 

Installation update: the new C&R radiator with integrated oil cooler arrived on Friday and looks really great. It's less bulky than I had expected and fits in the stock mounting holes as Kevin promised (he's been GREAT, by the way, and I highly recommend C&R on the basis of my very positive experience with them). For anyone who decides to do this, PM me, and I'll send you my notes on the installation (it's not that complicated, but I can share my parts list for the plumbing and some suggestions that will save you some time).

If all you're doing is replacing your radiator, it's pretty easy, although getting the coolant return line to fit around intercooler piping has been, for me at least, tricky, and I've yet to get it all plumbed together. I got stuck yesterday and quit after fussing, without success, to get the lines onto the radiator outlet. If you're also doing an oil filter relocation kit -- or, as in my case, switching from your existing oil filter relocation kit to a CM remote cannister filter -- the plumbing of oil lines is a PITA. In my case, the CM filter fits exactly where my old filter mounted (on the cross-brace that once supported the air box and still on the front side of the brace!), but my oil filter relocation kit was loose where it exited the block, and getting everything installed and tightened down with the turbo in the way of everything was a nightmare. That said, it all seems do-able, and I'm not worried yet.

As for the other things on my list (identified above), they're also coming along. I'm redoing my oil return line (from the turbo to the block) with A/N fittings and braided stainless lines. Again, the lack of space in which to work has been the biggest frustration. I've figured out that I can mount the t-junction -- which feeds the oil line to the turbo and the oil pressure sending unit -- to the back side of the cross-brace without having to extend the wiring for the oil pressure sending unit. So, I'm using that location rather than the strut tower brace. Given that I had some oil leaking where the t-junction used to be mounted directly on the block, this seems a good idea (thanks to DavePK, CJB80, and others who suggested this).

In short, it's all coming together -- just a bit more work than I had expected. I think I've also figured out how to get the EMS to read the voltages from the oil temperature sensor which I'll be mounting in the pan (using the GReddy drain bolt adapter), so that should be the last piece of that puzzle. Then, I'll start installing the Elda bar and, hopefully, if the seat and rail arrive in time, getting that all installed before heading to Laguna in a week and a half.

Best,
CB

 

[QUOTE]Originally posted by cbender
Installation update:

 

Do you know of an ECT sensor that will fit in the stock location and that has a documented cal table?

 

The coolant temperature sensor calibration figures for the stock sensor are correct, according to AEM, but I mistrust that conclusion frankly, based on my own experience and the experience of a couple of others on the boards.

That said, the new radiator certainly kept my temps within the normal operating limits using those calibrations -- perhaps a bit higher than I'd have liked on the track (210 degrees F) and perhaps a bit lower than I'd have liked (180 degrees F) on the street. But certainly within bounds.

Which leads me to conclude that the AEM calibrations may be right, afterall, but I'm still unsure.

CB