gkmccready

Tomorrow I'm putting the DRM Ron Davis EOC+TOC radiator into my '06 C6 Z51. I'm planning on changing the fluids at the same time. Recommendations so far are:

• 6qts Redline 10w40 Engine Oil
• 2qts Redline 75w90 Diff Lube
• 4.1qts Redline MTL

6qts & 4.1qts are out of the service & owners manual. Does the larger radiator expand the capacities?

Also, the stock coolant is 50/50 DEX-COOL and "clean drinkable water." I was planning on getting distilled water from the grocery store. The question is whether I should stick with 50/50 DEX-COOL or not? The car gets driven near daily as well as on track. But keep in mind I live in Redwood City, California directly between San Francisco & San Jose. It might get a few degrees below freezing a few mornings a year. Same question here about capacity; stock was 12.6qts.

Thoughts?

lbarnard

I have the DRM Radiator w/EOC (C5 ZO6); I run 1 gal of the Dex-Cool that already is mixed with water. I fill the balance using distilled water + 1 bottle of Water Wetter (optional) a lot of varying opinions on that. I track the car in the SE and water temps rarely get above 225.

Is the MTL fluid correct? I thought you needed ATF? Maybe does not matter either way I use RedLine High Temp ATF see if they have that for the MTL if that is the correct fluid.

For the rear-end still add the GM Posi-Additive regardless if the gear fluid has it.

gkmccready

The Redline website says the MTL can be used in transmissions that can use the Racing or High-Temp ATF. I was looking at the ATF when I saw that and confirmed the original recommendation.

I'll keep the limited-slip additive in mind; was told not to bother unless the rear chattered.

Thanks for the response!

gkmccready

Had to settle for 10w30 ... local Redline dealer was out of 10w40.

0Randy@DRM

If the car is in the garage, during a few cold nights. You shouldn't have any problems. I forgot about the tranny cooler, you may need to run the extra quart to fill the cooler We run the MTL for high performance drivers, like Glen.

Run some extra oil in the pan just like any wet-sump car when at the track. 3/4 to a full quart.

Most tracks don't like antifreeze in the car for HPDE, and racing alike. It becomes like ice out on the track.

Randy

gkmccready

The stock owners manual says 4.1qts and doesn't call out the Z51 as different. I'll run back and grab another one just in case. Thanks Randy!

gkmccready

Nobody seems to get too worked up over it for the HPDE stuff. I fill the racecar with distilled and a bottle or two of water wetter. Is that what you'd recommend here, too? The 50/50 mix is good to -34F which is way way overkill.

mgarfias

Offical ron davis reco is 50/50 dexcool/water.

However, I have it on pretty good authority that I should run like 20-25% of the green stuff (not dexcool), plus water.

Bill Dearborn

I wouldn't do that. GM doesn't recommend the green stuff for the LS aluminum engines. I ran the DRM Ron Davis racing radiator with 50/50 Dex Cool with no problems in my 97 for 3 seasons and my 03Z for 6 seasons. You can still run a 195 degree thermostat. On the track at WOT even in 90 degree heat the engine will run at 200 degrees. Biggest problem I had was getting the oil temp high enough on cool days. On a 40 degree day the oil temp wouldn't go over 100 degrees unless I ran the car in third at highway speeds.


Bill

gkmccready

Install was 5.5 hours at TC Design Fab in Milpitas, CA. Joe and Tony doing great work as always. We topped up whatever was left in the system with distilled water and a bottle of water wetter. Changed the diff fluid while we were at it. Tranny with Redline MTL feels better than whatever the factory fill is.

The ride up 101N saw 240F/240F in traffic doing about 65mph; it's over 90F today. I'll know a bit more tomorrow when it's fairly clear sailing to work. Using the stock lines compared to the stock C6 Z51 radiator I don't think I'll have the trouble of the oil not warming up...

trackboss

240 seems way too hot cruising at 65 on the freeway. Check for air in the system.

gkmccready

Yeah, that was what I was waiting for somebody to say. I'll pop the lid tomorrow morning and top it up after it cools all night.

trackboss

When I bleed mine I leave the cap off and run the motor to until the thermostat opens then have someone rev the motor. All done with the coolant level low so it doesn't get all over the place. Then top off as necessary. For the most part these cars are self bleeding. On mine I run bleed lines from all four corners of the heads. If the heads are off I would recommend tapping the holes for 1/8" npt and install AN fittings with lines to bleed. Then there is no need to deal with the factory hard lines around the intake manifold.

mgarfias

I can't remember where I got them, but I found some aluminum deals that bolt up in place of the stock steam vents/block offs and provide 1/8" NPT. I was able to do that with the manifold in place.
If I ever put new heads on, I'll have them tapped directly.

mgarfias

Found em: http://s41657.storefront-solutions.c...l.aspx?ID=3289
Probably another $50-60 in hose and fittings to get it plumbed in.

meldog21

Mine water stays at 192 during normal (for me) driving in exactly the same area. Either it's air in the system or something else is not right.

Dog

gkmccready

Definitely a big air pocket. Car sucked down near another gallon of distilled water this morning. I'll take it to work and check it again tomorrow morning. That's water wetter, 2 full gallons yesterday, plus almost a full gallon today into a system that's 12.6qts so it's got to be close this time around. They did say to check it this morning after it sat and cooled overnight... I certainly wasn't expecting it to take another 4qts though.

gkmccready

Drive in never saw water go above 210, mostly hovered around 195. That looks much much better.

0Randy@DRM

trackboss

mgarfias, good find. Those fittings are cool. When I take the heads off I think I'll still tap them and install a normal ntp to an fitting just to simplify things and eliminate the gasket. In the mean time, those would be great.