Radiator for C4
Burning Brakes
Joined: Sep 2017
Posts: 939
Likes: 168
I know this is probably a frequently asked question...
But... I have a 1989 that I frequently race, NCCC high speed and low speed AutoX, drag racing and some track days on road courses.
As most people know, C4's run hot. Keeping them running cool even in normal driving is a problem. Keeping one cool pushing it hard is an exercise in frustration. I've already done a few things... I bought a Z51 oil cooler, which has been pretty effective at keeping the oil temps under control. Before that I was seeing 260+ on the oil, now it rarely goes over 240. The fan not coming on until 232 is just way too late, so I also had a fan override installed for use when racing which helps on the coolant temp, but has unfortunately caused my fan to wear out. It is making a lot of noise, is wobbly and doesn't seem to be doing an adequate job. I have a used fan located I can put in, but I also have a dual fan setup from a 1993 I might try to fit if that might be a better choice. I also have a Z51 "pusher" fan which I bought off eBay that I was going to install. I'm not sure if the original style single large main fan plus the Z51 pusher is a better choice or the 1993 dual smaller fans... Or the 1993 fans + the Z51 pusher. And do I want to consider different sensors or combinations of manual overrides to wire this thing up. Anyway, looking for info an opinions on what way to go here.
Now -- the main reason for this post... Radiators... While my original radiator seems to be OK, it doesn't leak nor does it appear to be full of sediment and blocked or anything... But it just seems inadequate. I'm wondering what the best, or at least a really good aftermarket radiator would be? Something that will fit without a lot of modifications but offer better cooling. DeWitts? Griffin? Any others I should look at? Where's the best place to get something like that?
But... I have a 1989 that I frequently race, NCCC high speed and low speed AutoX, drag racing and some track days on road courses.
As most people know, C4's run hot. Keeping them running cool even in normal driving is a problem. Keeping one cool pushing it hard is an exercise in frustration. I've already done a few things... I bought a Z51 oil cooler, which has been pretty effective at keeping the oil temps under control. Before that I was seeing 260+ on the oil, now it rarely goes over 240. The fan not coming on until 232 is just way too late, so I also had a fan override installed for use when racing which helps on the coolant temp, but has unfortunately caused my fan to wear out. It is making a lot of noise, is wobbly and doesn't seem to be doing an adequate job. I have a used fan located I can put in, but I also have a dual fan setup from a 1993 I might try to fit if that might be a better choice. I also have a Z51 "pusher" fan which I bought off eBay that I was going to install. I'm not sure if the original style single large main fan plus the Z51 pusher is a better choice or the 1993 dual smaller fans... Or the 1993 fans + the Z51 pusher. And do I want to consider different sensors or combinations of manual overrides to wire this thing up. Anyway, looking for info an opinions on what way to go here.
Now -- the main reason for this post... Radiators... While my original radiator seems to be OK, it doesn't leak nor does it appear to be full of sediment and blocked or anything... But it just seems inadequate. I'm wondering what the best, or at least a really good aftermarket radiator would be? Something that will fit without a lot of modifications but offer better cooling. DeWitts? Griffin? Any others I should look at? Where's the best place to get something like that?
I installed larger radiator, also had to change to smaller condenser on 1984, 180* thermostat and a 200* fan on 185* off fan switch. run from 185* to 205* and trans 160*. I would try thermostat and fan switch first. dewitt radiators have custom rubber mounts
Le Mans Master
Joined: Aug 2017
Posts: 6,942
Likes: 1,490
From: New Jersey
No, this won't work to turn the fans on. Here's why:
The fans are not turned on by the position of the switches or controls for A/C. The fans are turned on by the ECM AFTER it receives a "fan request" signal from the high pressure switch when the pressure in the high-side / condenser gets high enough to need the airflow of the fans.
If the compressor is unplugged, there will never be enough high-side pressure to turn the fans on.
Now, there's "some thinking".
The fans are not turned on by the position of the switches or controls for A/C. The fans are turned on by the ECM AFTER it receives a "fan request" signal from the high pressure switch when the pressure in the high-side / condenser gets high enough to need the airflow of the fans.
If the compressor is unplugged, there will never be enough high-side pressure to turn the fans on.
Now, there's "some thinking".
Now... Could you also jumper or disconnect the high side call out switch then to have it work depending on if it's NO or NC? It may be possible that way?
Le Mans Master
Joined: Aug 2017
Posts: 6,942
Likes: 1,490
From: New Jersey
