Adding Intercooler w/o Computer Swap

[grantolson87]

Hey Guys,

Newbie here, Just purchased a 1984 Hatchback 20th Anniversary Edition with the 2.3 EFI Turbo. I have been scouring this site as well as another turbo ford site and to find some info regarding adding an SVO intercooler.

I just purchased an SVO intercooler on eBay for 25.00 and it looked to be in good shape. My question is whether I can add this intercooler without upgrading to the 35lph injectors and SVO computer (not sure if VAM would have to be changed too?) or would I be ok just modifying the turbo oulet to fit the intercooler?

Would there be any harm to the engine in adding this intercooler without making the other upgrades? Do you think it may acutally have a negative effect on performance without the mods?

Also (havent researched this one as much) my car overheats anytime im sitting still. I have the electric fan but it doesnt kick on (or does so at a really high temp that I dont let it get to,) is it easy to change the temp that it comes on at? Am I better off just buying a universal one from summit/etc?

Thank you for any help you can offer. I am a big fan of this site and I'm sure I'll be spending alot of time here.

-Grant

[MAPSVO]

No issue adding intercooler, however the turbo compressor housing would have to be changed. The SVO intercooler attaches to the turbo with large hose connections, the stock non-intercooled turbo has a flange and a solid pipe that goes up to the throttle body connector. Without having a source of fresh air to blow through the intercooler it might not help much at all.

The temp controller could be a bad controller which is located under the steering column and to the left (I think) inside the car above your left knee/ankle or possibly a bad fan motor. Unhook the plug at the fan and jump 12volts and ground to the two terminals and see if the fan runs, then go from there.

There are inexpensive adjustable fan control systems ($30-$40) available at autozone, advance, or about any auto parts store that work pretty well and totally mount out in the engine compartment to keep all the wiring out from inside the car. I have used these more than once with good results. The original control system cannot be adjusted.

Hope this helps some.

[2eyed4eyes]

The intercooler does not require any upgrades at all. it's sole function is to lower air temp as air flows through it and into the throttle body. An intercooler actually does not increase HP but the cooler air does significantly decrease detonation and can allow more boost. I would recommend a front mount intercooler because they are larger and more efficient at cooling than the top mounted SVO and TC intercoolers. The TC intercooler is also a better option. They are bigger than the SVO version.

[Turbo_Pace]

If your fan is bad I have one that I'll let go, was on my car that I got from an 85 svo I think they are the same but not sure just let me know, thanks.

[Jimmy2.3Mustang]

The housing on the left is the stock GT Turbo, early Turbocoupe, or Merkur compressor housing. The one on the right is the style used on the SVO. The SVO type usually goes for $50-100, and they aren't all that hard to find, but it's still not worth the trouble to add the stock intercooler since it sits right on top of the exhaust manifold and turbocharger. Remember, warm air rises. A heat exchanger isn't going to be too effective when the air on the outside is hotter than the air flowing through the cooler.

The stock fan system is a really poor design. Take a look at the controller/harness under the dash on the drivers side. It's not unusual for the harness to melt. If it's not melted, you can bypass the fan switch by back-probing the yellow wire with the red stripe to ground and the fan should come on with the ignition on. If the fan doesn't come on, check for 12v at the fan harness. If you have voltage and the fan doesn't run, it's the fan motor. If you don't have voltage, it's either the controller module, or the wiring in between.


There are several ways to work around the stock fan control issue. A pair of normal heavy duty relays can be wired up to take the place of the IC, or you can make a circuit from scratch, or use a later computer with built in fan control, etc... A search would bring up several solutions. The stock setup can work, but it fails often.

[grantolson87]

It doesnt sound like I will gain much with the intercooler I ordered, I think I will hold off on the top mount SVO intercooler and save up for a front mount.

I pulled what I believe to be the fan temp controller (underneath drivers lower dash panel) and it was all hacked up with wire spliced and such. I think my best best is going to be with an aftermarket fan temp setup that is adjustable, since the factory unit is not.

Thanks for your help guys, it gets me going in the right direction.

-Grant

[Jimmy2.3Mustang]

The fan on/off point in the factory system can only be adjusted by replacing the fan switch with one that switches on/switches off at a lower temp. Trouble is an aftermarket switch that works at reasonably lower temps is about $40, and it would still be a generic part, it wouldn't plug right into the harness without modifications. It's probably easier and cheaper just to use an aftermarket control.

The other alternative is using the 87-88 Turbocoupe computer. Many people make the change just for the large VAM and injectors, or increased performance, but the later computers have built in control for two fans. Connecting the computer to control the fans, is just a matter of wiring up a couple relays, and connecting a couple wires to the computer. Of course without computer tweaking tools, you still can't adjust the on/off temps. I want to say the LA3 turns the fans on at 200* on one circuit, and 220* on the other, in stock form.

[grantolson87]

If I use the aftermarket cooling kit, is there any harm in leaving the original module unplugged? Does it send any data to the ECU to run the EFI or any other guages/sensors?

[Jimmy2.3Mustang]

Deja vu... No, all it does is control the fan. Leaving it disconnected won't hurt anything.

[grantolson87]

Thanks Jimmy2.3