What Spal fan?

[Naplm00]

Well im about to start my M42 rad swapout.

I dont have AC or condensor up there and id like to put in a fan up front, a pusher.

What Spal model should I go with? do they come with the mounting studs for the Rad?

also if i have no AC components in my car how can i wire this bad boy so it comes on automaticly?

[jlevie]

A 16" fan rated for at least 1800cfm will be sufficient. Do not try to mount the fan via the radiator fins. That type of mount can eat a hole in a radiator tube. Fab up some sort of bracket to mount fan to either the car body or radiator top and bottom plates.

Use a 82-83C thermo switch in the radiator to control a relay to operate the fan. A SPA relay kit has everything you need except the thermo switch.

[NC325iC]

summit sells a 16" flexalite reversible fan for $122ish

or a slimline fan for $145ish

both flow over 2k cfm, the reversible one is a curved blade so its quieter

[Naplm00]

ok cool, what is the stock thermo switch rated at?

88 325ic

[jlevie]

The stock temp switches for an E30 are 91/99C. If you substitute an electric fan for the engine driven fan you need a thermo switch that operates just a bit above the rating of the thermostat (80C). So an 82-83C thermos switch is just right.

[StereoInstaller1]

I want one of these (one of these days)

[ldsbeaker]

that's pretty dang cool. (no pun)

[Naplm00]

The stock temp switches for an E30 are 91/99C. If you substitute an electric fan for the engine driven fan you need a thermo switch that operates just a bit above the rating of the thermostat (80C). So an 82-83C thermos switch is just right.

Well shit, the thermo i juts bought from pelican is the wrong themp then

I just bought a 75 degree from pelican


Also while looking through pelican I could not find this thermo switch that mounts in the rad with the 3 prong plugs

little more help for a amatuer?

[jlevie]

The stock thermostat for an M20 engine is an 80C unit. You can use a 75C thermostat an still use an 82-83C thermo switch. BavAuto has an 82C thermo switch that mounts in the radiator where the OE dual thermo switch would normally be.

In a northern climate, you probably want an 80C thermostat to provide more cabin heat.

[Naplm00]

Ugh, ok thanks for the update, ill order another thermo and switch

[Naplm00]

thanks for the great info, ill be sticking with the 75c because now that I think of it...i have a 75 c in there now and my heat is plenty hot.


I ordered that thermo switch and a flexlite curved reversable pusher fan and some stand offs so i dont have to mount it in the core.


A question on the wiring, can I just wire the fan to the stock harness that the aux fan was wired to? so i dont have to install any relays or anything? seems beefy enough

Ill write up a nice how to when i finish this lil project

[jlevie]

You can use the existing low speed relay to operate the fan. Some mods to the existing wiring will be necessary. A nice feature of adding a relay kit is the ability to add a manual override switch in the cabin allowing you to turn on the fan even if the thermo switch doesn't.

[Naplm00]

ok sounds good,

did some research; for the record in a 88 vert:

Fan wiring:
Brown = Ground
Black (at the fan) or Black/Green (after fan connnector) = low speed positive feed

Thermo switch:
Green/Black = power feed (must be connected)
Black = Low speed relay feed (the one you want to connect to the new hermo switch)
Black/Brown = High speed relay feed (do not connect)

[StereoInstaller1]

I use a switch and the stock relays etc.

I just like being able to turn it on when I want.

[Naplm00]

when you say stock relays, you mean how i describd above or did you wire in your own switch?