Radiator options

[Karl]

Originally Posted by Pete

Karl,5th and 6th gear issue is not the UD pulley, stock pulley has the same issue so lets not freak out here.

The UD pulley slows the pump down if you had cooling issues before Hib is right went the wrong way with the UD pulley.
The UnderDrive pulleys give you more RPM before it goes to bypass,the Road Racing guys like this.

Heck,my Z has no A/C condenser, no oil cooler, 160 T-Stat, fans on at 175*, stock pulley and still have the 5th 6th gear issue.
Like Dom said when she gets moving she cools faster.

The C4 is a bottom feeder sucks up a lot of crap, take radiator out clean it very good,usually you will find a birds nest in there you will be suprised i would suggest either take Dom's radiator and clean it up or buy new cause you don't wanna do the job twice not a fun job.

I have these pulleys on my Z (stock size).
What i like about the pulleys is they are aluminum, half the weight of the OE steel pieces between PS,WP & ALT i saved about 2-3 lbs and they look nicer then the OE pulleys and get them in any common color,even purple.

By the way you will not get her to run below 220* on a 90+* hot n humid Chicago parking lot traffic day, i tried everything this is why i don't have it anymore the ones that say there's stays at 200 or 210 they are talking at speeds not parking lot traffic.

Pete

I never had any overheating issues unless I was stuck in traffic with the AC on.

[Pete]

Originally Posted by Karl

I never had any overheating issues unless I was stuck in traffic with the AC on.

Karl,not overheating but cooling her down with A/C on in traffic.
I should've made it more clear with the A/C on in traffic i just thought it was understood.
A friend has a 1994 with 17k miles and has cooling issue with A/C on in traffic.
This is C4 issue.
I think a nice pusher fan could help.
Most BMW's,Mercedes, have pusher fans my Infiniti has belt driven fan and an electric pusher fan.

Pete

[XfireZ51]

And I swapped in a Fluidyne because I experienced overheating when driving in the Woodward Cruise. Ambient temps must have been over 90F. DID NOT have A/C on. Traffic was crawling. Took an hour to move 1 mile. With the Fluidyne installed, I actually raised the Fan Temps.

[Karl]

Originally Posted by Pete

Karl,not overheating but cooling her down with A/C on in traffic.
I should've made it more clear with the A/C on in traffic i just thought it was understood.
A friend has a 1994 with 17k miles and has cooling issue with A/C on in traffic.
This is C4 issue.
I think a nice pusher fan could help.
Most BMW's,Mercedes, have pusher fans my Infiniti has belt driven fan and an electric pusher fan.

Pete

Here is the thread we were texting about earlier

http://www.zr1.net/forum/showthread....ght=pusher+fan

[Pete]

Originally Posted by Karl

Here is the thread we were texting about earlier

http://www.zr1.net/forum/showthread....ght=pusher+fan

Thank You Mr. Davila
Now the question remains is it Frank Approved.

Pete

[Hib Halverson]

Originally Posted by Karl

I have noticed this.

It seems that your original comment implied the under drive water pump is not worth any type of performance gain versus stock. I have always thought a under drive pump will add some power to any engine.

So do you think there is any performance gain, hp wise, with using a under drive water pump?

Regardless of any power gain, why would I want to under drive my water pump and make cooling worse? But..I digress.

Do I think there is any power gain by under driving the coolant pump? At high rpm there might be a small gain.

[Hib Halverson]

Originally Posted by Pete

Karl,not overheating but cooling her down with A/C on in traffic.
I should've made it more clear with the A/C on in traffic i just thought it was understood.
A friend has a 1994 with 17k miles and has cooling issue with A/C on in traffic.
This is C4 issue.
I think a nice pusher fan could help.
Most BMW's,Mercedes, have pusher fans my Infiniti has belt driven fan and an electric pusher fan.

Pete

Why not solve the problem rather than adding "pusher fans"? It might be easier and less expensive.

[Pete]

Originally Posted by Hib Halverson

Why not solve the problem rather than adding "pusher fans"? It might be easier and less expensive.

Hib,i have tried a lot of different ways to keep the temps from creeping up in traffic with A/C on, clean radiator,new radiator,big radiator,fans on early,low temp t-stats,and this is on multiple Z's.
So i yanked the A/C on my Z and decided if i'm going to drive in traffic on hot summer days i will take my other car with no worries,now my Z is just a toy/weekend warrior

If you have some input/suggestions on this please let me know i'm always open to suggestions/input that i can try,maybe i missed something.

I even tried a 55 GPM electric pump worked good with no A/C but again with A/C on in traffic temps would creep upwards soon as i get some speed it would drop like a rock my conclusion need more air thru the radiator in traffic.

I'm one guy that likes his temps down.
I don't like to see temps over 220-225 if we can keep them steady at 200 it would work for me (A/C on in traffic).

We have to understand when your in summer traffic it could take you
1 hour to go 2-3 miles (on the highway) it's stop n go you'll move 5 feet stop 2 minutes move another 5 feet it's ridiculous no air moving thru the radiator.

I'm pretty sure Mr Davila has also tried different things to keep temps down he's still trying from the looks of the install of a pusher fan,this was going to be my next move since Mr Davila did it with good results i don't have to experiment.

What got me thinking about the pusher is my Infiniti and other luxury cars have belt driven fans and an additional electric pusher fan when i turn my A/C on in the Infiniti the pusher fan comes on,this gets me to think if these high priced luxury cars (BMW & Mercedes) did not have cooling issue why add an extra part they could be saving millions,just a thought.


My set up now is no oil cooler to me it's a waste since t-stat doesn't fully open till 200*, no condenser, 160 t-stat,stock clean radiator,fans on at 175* off at 170*,70/30 mix, Redline water wetter i have been using Redline water wetter for many years even in my other cars, when my Z sits and idles you'll hear my fans come on and go off it will keep cycling like this no matter outside temps,in traffic she will stay steady at 180-185 soon as i get some speed she cools down fast but i would like to keep her steady at 175* no matter what.
Oil temps are always within 10* of coolant temps.
I do not road race my Z just 1/4 and 1/2 mile, love to do 1 mile.

Man i think i broke a finger typing all this.
Pete

[Dynomite]

Originally Posted by Pete

Hib,i have tried a lot of different ways to keep the temps from creeping up in traffic with A/C on, clean radiator,new radiator,big radiator,fans on early,low temp t-stats,and this is on multiple Z's.
So i yanked the A/C on my Z and decided if i'm going to drive in traffic on hot summer days i will take my other car with no worries,now my Z is just a toy/weekend warrior

If you have some input/suggestions on this please let me know i'm always open to suggestions/input that i can try,maybe i missed something.

I even tried a 55 GPM electric pump worked good with no A/C but again with A/C on in traffic temps would creep upwards soon as i get some speed it would drop like a rock my conclusion need more air thru the radiator in traffic.

I'm one guy that likes his temps down.
I don't like to see temps over 220-225 if we can keep them steady at 200 it would work for me (A/C on in traffic).

We have to understand when your in summer traffic it could take you
1 hour to go 2-3 miles (on the highway) it's stop n go you'll move 5 feet stop 2 minutes move another 5 feet it's ridiculous no air moving thru the radiator.

I'm pretty sure Mr Davila has also tried different things to keep temps down he's still trying from the looks of the install of a pusher fan,this was going to be my next move since Mr Davila did it with good results i don't have to experiment.

What got me thinking about the pusher is my Infiniti and other luxury cars have belt driven fans and an additional electric pusher fan when i turn my A/C on in the Infiniti the pusher fan comes on,this gets me to think if these high priced luxury cars (BMW & Mercedes) did not have cooling issue why add an extra part they could be saving millions,just a thought.

My set up now is no oil cooler to me it's a waste since t-stat doesn't fully open till 200*, no condenser, 160 t-stat,stock clean radiator,fans on at 175* off at 170*,70/30 mix, Redline water wetter i have been using Redline water wetter for many years even in my other cars, when my Z sits and idles you'll hear my fans come on and go off it will keep cycling like this no matter outside temps,in traffic she will stay steady at 180-185 soon as i get some speed she cools down fast but i would like to keep her steady at 175* no matter what.
Oil temps are always within 10* of coolant temps.
I do not road race my Z just 1/4 and 1/2 mile, love to do 1 mile.

Man i think i broke a finger typing all this.
Pete

I concur.........mostly

I am talking 100+ deg F days and stop and go traffic or long stop lights in succession.

I like my LT5 running around 190 deg F to 200 deg F on the HOT days for condensation and best performance. I use the Haibeck LT5 Performance Chips in ALL ZR-1s which turn Fans ON at 205 deg F and OFF at 200 deg F.

Now also keep in mind you are pulling air through a three stack set up including the Oil Cooler, AC condenser, and Radiator. That is where the pusher fan concept will help in stop and go traffic or at stop lights if you want to go that route. I think Daryll (AKA Goldcylon) experimented with higher flow rate dual fans which would also help keep LT5 Coolant temperatures down on HOT days.

A. Now where I think concepts are over blown.............
The steady state of the coolant flow is identical at HOT ambient temperatures (100+ deg F) no matter when the fans first came on and no matter when the thermostat first opened. (kind of like using lighter weight front of engine pulleys or lighter weight flywheels where the hp gain is only on rotational acceleration and not on the steady state of engine RPM).

Using 165 deg F or anything less than 180 deg F thermostats is a bit of a waste and a negative on colder days. A 180 deg F and a 165 deg F thermostat are both fully open at the LT5 operational temperatures I am seeking of 190 deg F - 200 deg F (maybe 215 deg F on HOT 100+ deg F days). Yes you may if other modifications allow it on 100 deg F days drive around at 175 deg F and approach a stop and go situation with a cooler engine buying you some time at the stop and go. But that is about the only difference.

Same goes with turning fans on at lower temperatures than 205 deg F. I do not want to run around on cooler days with the fans always running when they do not have to in view of my 180 deg F thermostat and in view of the 190 deg F - 200 deg F LT5 temperatures I am seeking (maybe 215 deg F on HOT 100+ deg F days).

B. What to do to keep the LT5 Cooler in Stop and Go or Long Stop Lights on HOT (100+ deg F) days..................
So....if you want to get serious and like Pete suggests....do all the normal maintenance like clean radiator, oil cooler, and AC condenser of trash (keep the stack clean and that includes keep the stacks clean of any oil). If you want additional LT5 performance get yourself one of the Haibeck LT5 Performance Chips which turn Fans ON at 205 deg F and OFF at 200 deg F.

If you really want to get serious......install an auxiliary electric pusher fan or higher flow rate dual fans. And/or install an Aluminum After Market Radiator that offers greater cooling effect with the same coolant flow rate (but at the same time may be a bit more restrictive on the air flow rate).

If you really really want to get serious.....remove the oil cooler and AC condener. But when I am that serious I just turn AC off and if I have to .....turn the engine off.

C. Underdrive and Overdrive Water Pump Pulleys as they relate to Engine Cooling...............
Oh.....just to complete this little discussion I am having
Using a larger diameter water pump pulley (Underdrive) may buy you some engine cooling at higher RPMs if you are in the 6000-7000 rpm zone for very long where the water pump may be cavitating at that high rpms with a standard diameter water pump pulley. On the other hand, using a smaller diameter water pump pulley (Overdrive) may buy you some engine cooling at lower rpms in stop and go traffic where the coolant flow rate is normally low with a standard diameter water pump pulley.

See LT5 Engine Cooling Issues on Hot Days

See LT5 Engine Optimum Operating Temperatures

See Primary Cooling Fan Operation Criteria TIPS

[Karl]

Pete hit the nail on the head.

I have got caught in rush hour traffic on hot and humid days and as long as the car is moving there are no worries but once stuck and not moving things begin to heat up.

I am 100% convinced that air flow is the key and like Hib said earlier GM half assed on the LT-5 cooling with the standard C4 radiator. Either higher CFM fans (like that in the Ford Taurus, Crown Vic, or Dodge Vper) or a simple pusher fan up front. Seems like Tony's test results confirm it works.

I never had cooling problems with the under drive water pump pulley. Just standard C4 warming up while not moving in traffic with the A/C on. I would like my car to run in the 180*- 190* range all the time if I had it my way. My new 3 core aluminum radiator should be here soon and in the car right away.