LT5 Cooling and Radiators

[XfireZ51]

Hib,

I installed what I believe would be the Flyidyne you guys developed. It does "drop in". We haven't had incredibly hot temps here in Chicagoland, but it does the job w typical coolant temps in the 85-88C range. Haven't seen anything over 95C. And have not yet tried A/C. Just no need to so far. The biggest issue I had was getting the motor up to operating temps w ambient air at 0-10C. Had it out last winter on a dry day and it would not go above 50C.

[Dynomite]

The Fluidyne All Aluminum Radiator is now in the Last 1990 sold to public #3032. It dropped right in with no issues. I wanted to keep this as stock as possible without having to shave the Fan Baffles for a Ron Davis Radiator Fit.

1990 ZR-1 (Number 3032 - The Last 1990 Sold)
TB Coolant Blocked at IH
Fluidyne Radiator
RC Injectors
Haibeck Chip
Billet Aluminum Belt Tensioner Pulley
Billet Aluminum Power Steering Pulley

Originally Posted by Hib Halverson

There was only one Fluidyne which fit all late C4s (i.e.: anything with the tilted back radiator) and that's the one I developed with Jim Van Dorn's help.

Actually, we did all the hot weather testing in Palm Desert working out of Jim's old shop. We did that in September and the OAT then was actually even hotter than it was in Indio last Saturday–115° stick in my mind, but I'll have to confirm that. We tested on CA SR74 going uphill at about 8/10s. You can find SR74 on Google Maps by looking for the junction between US 111 and CA SR74. Once that road get curvy on the west side of Palm Desert is where we tested. The locals call it "7-level hill". Running the engine that hard, believe it or not, had lower ECT because the RPMs were up in the area where the system actually cools better, however, our sustained rpm was not so high that the coolant bypass became a problem.

I made a lot of posts to the ZR-1 Net back then explaining the Fludiyne design and how we tested it. Back then, our target competitor was the Ron Davis. I don't know what Davis sells now, but back then his radiator for late C4s was not a bolt-in and required fabrication work to fit.

The Fluidyne not only cooled better than what Ron Davis was selling at the time, but it dropped right in the stock cooling stack.

I'll look around in my several 1TB hard drives to see if I have any of that old stuff.

Also, if there's anyone here who knows how to research old ZR1Net posts from the 1998-1999 period, you may find my discussions of the Fluidyne.

I am probably the last one to install (Re-Install) a Fluidyne Aluminum Radiator in May 2015. The Fluidyne was like new with very little trash on the front face. I simply removed it from 1990 ZR1 #2067 having SW Offroad Exhaust and intstalled it back into ZR1 #3032 having Stock Exhaust. I did check Fluidyne Radiators in May 2015 looking for that Fludyne Aluminum Radiator since it did not have any numbers on it. I could not find a Fluidyne Radiator for a 1990 ZR1 Corvette.

That Fluidyne Aluminum Radiator was a very nice Radiator (a bit thinner than the Ron Davis) and having the Fluidyne All Aluminum Radiator out on the floor I just decided to install it back into a Stock 1990 ZR1 since that Fluidyne required NO Fan Shroud Trimming and it was a Mint Condition ALL Aluminum Radiator. I removed the Fluidyne Aluminum Radiator from ZR1 #2067 for cleaning and identification (which it did not really need any cleaning and it did have the Name Fluidyne but no Numbers).

I did run the Fluidyne Aluminum Radiator in ZR1 #3032 but the ambient temperatures were only in the 70s so not a real test but it seemed to cool just fine.

It appears that Fluidyne Aluminum Radiator I installed in ZR1 #3032 is no longer made or is identical for another application and just not listed for a C4 ZR1 Corvette.

That Fluidyne Aluminum Radiator would definitely be a very nice ZR1 Radiator to replace the ZR1 Stock Radiator
if it were available from Fluidyne Fluidyne Radiators

[XfireZ51]

After installing the Fluidyne, I actually modified the calibration to RAISE THE fan temps.

[PhillipsLT5]

I bought a fluidyne years ago on Hibs suggestion/review, all good in HOT AZ

[mike100]

My contribution to this topic is that I gave the alternator and 12v system a break by offsetting fan1 and fan2 to turn on at 2 deg different temps so you don't get that massive lcd display dimming inductive load kick on all at once.

[Dynomite]

Originally Posted by PhillipsLT5

I bought a fluidyne years ago on Hibs suggestion/review, all good in HOT AZ

I did run the Fluidyne Aluminum Radiator in ZR1 #3032 but the ambient temperatures were only in the 70s so not a real test but it seemed to cool just fine.

It appears that Fluidyne Aluminum Radiator I installed in ZR1 #3032 is no longer made or is identical for another application and just not listed for a C4 ZR1 Corvette.

That Fluidyne Aluminum Radiator would definitely be a very nice ZR1 Radiator to replace the ZR1 Stock Radiator
if it were available from Fluidyne Fluidyne Radiators

[XfireZ51]

Originally Posted by mike100

My contribution to this topic is that I gave the alternator and 12v system a break by offsetting fan1 and fan2 to turn on at 2 deg different temps so you don't get that massive lcd display dimming inductive load kick on all at once.

Mine come on at 2 different temps also.

[Hib Halverson]

After a long search of two different computers, I found my original notes written to the management of Fluidyne in September of 1999, after Van Dorn and I finished our hot weather testing of the Fluidyne Radiator

My memory as to the ambient temperature during those few days of testing was not so good. In an earlier post, I said it was 115°. Actually the hottest OAT we observed during testing was 111°.

The memo to Fluidyne has been converted to a .pdf. It's an interesting insight to the kinds of stuff the original Auto Masters and myself were doing 16 years ago. At the end of the memo is all the testing data. Tests #8 and #9 were both done on CA SR74 in the "7-Level Hill" section and were run uphill at near racing speeds, i.e.: about as hard as I could drive given I had to stay on the right side of the road. The distance from my starting point to the top of 7-Level was 4.9-mi. I included a Google Maps screen shot of the course used in testing. All the mountain road testing was done uphill.

The radiator uses for that test is still in my car today. The only difference in my cooling set-up now is I use 100% water and RLWW rather than 75% water and 25% Dex-Cool.

If anyone has any questions, post them and I'll try and answer.

[Billy Mild]

http://www.corvetteforum.com/forums/...-radiator.html

I saw this post about a upgraded radiator from amazon. It is has more cores and appears to help with cooling.

[RussMcB]

Originally Posted by Billy Mild

http://www.corvetteforum.com/forums/...-radiator.html

I saw this post about a upgraded radiator from amazon. It is has more cores and appears to help with cooling.

Thanks for sharing. It's good to hear about all options. I read the reviews and they are mixed (with neither high praise or very negative). It appears to have the auto transmission cooler section, which I'd guess would take away from the total cooling ability.

It's probably a good choice for some C4 folks wanting to improve from stock, but I'd think most here would rather spend a bit more and get known high quality.