I've got a stock L24 and tore the intakes apart to polish them. I've got them mostly back together and setup but I don't have anything from the hole facing the firewall on the rear intake (opposite the balance tube). Can someone check their manifold and tell me what screws into that side? Thanks

If you are talking about the actual intakes and not the balance tube, it should be have a nipple connection for coolant line or possibly a thermostat switch with a coolant connection

Mike

somewhere is a connection to the brake booster.

Originally posted by Daniel

somewhere is a connection to the brake booster.

That would be on the balance tube assy, not on the intake manifold itself.

The hole at the rear of a 1972 E88 Intake would be for water to flow through passages in the intakes and the 3 screw SU's. Late 72's might have the thermostat valve, but early 72 Z's would just have a "nipple".

Originally posted by Bruskiz

If you are talking about the actual intakes and not the balance tube, it should be have a nipple connection for coolant line or possibly a thermostat switch with a coolant connection

Mike

Mike has it right! The fitting that threads into that hole is a thermo switch for coolant. It opens after the coolant is up to temp. to keep the intake manifold a constant temp.( the intake is designed to close to the exhaust manifold ).

- Jeff

On the front end of the intake manifold the fitting goes to the thermostat housing.

- Jeff

From the thermo switch the steel tube,connected to the switch with a short rubber line, goes around the back of the head to the heater hose.

- Jeff

My early 72 came from the factory without a Thermo switch in that location. It just has the same nipple fitting that is on the front end of the intake. Water constantly circulates through the manifold/carbs (or it would, if I hadn't blocked it off at both ends!)

***EDIT*** Err, I made a mistake, there is a Thermo Valve at the rear of the Intake Manifold on my car. I didn't recognize it as such. Sorry for any confusion I caused.

Ok, thanks. I'll take a look at that stuff in the morning. Just got all my front suspension together today.

Just another quick question since you guys brought up heater hoses. I got new hoses for the passenger side of the block and plugged them in where they seemed to want to go but I looked at a picture I had taken and written on referencing to the two hoses, and I think I may have hooked them up wrong. The hose that runs from the water inlet, down the length of the block and into the firewall goes into the heater? And the hose connected directly to the rear of the block is hooked up to a flow switch?

Originally posted by blitzkraig

.............The hose that runs from the water inlet, down the length of the block and into the firewall goes into the heater? And the hose connected directly to the rear of the block is hooked up to a flow switch?

AIR, The hose from the inlet that runs down the length of the block and goes to the firewall and into the heater has a metal pipe "T" (actually looks like a "Y") fitting that branches to a pipe that goes around the back of the engine to connect to the rear of the intake manifold. The other hose coming OUT of the heater, comes through the firewall and goes into the rear of the cylinder head.

Do you guys think it is necessary to connect the hose to the intake manifold? Supposedly the coolant was to flow through the intake manifold to bring the carbs up to operating temp then the thermostat (the one on the back between the manifold and the fire wall) would close when the temp is appropriate. Now wouldn't it be better to keep the carbs cool by not allowing the water flow through the manifolds? This would keep the intake air cooler.

Ok, so I've been eye balling pictures I took before I tore the engine apart and I've been rummaging through the hoses I tore off. I don't think the coolant was hooked up to the manifolds. My guess is when my dad had the smog equipment taken off maybe the mechanic took off those hoses too? Do I need the lines hooked up? Does it help or hinder performance?

On the other topic, I think I figured out why the heater hoses were switched around. I ordered those two hoses and the hose from the manifold to the vent tube on the driver's side from MSA. In the boxes I recieved I only got two twisted hoses, so I think I cut the PCV hose thinking that was one of the heater hoses.:stupid: Time to heckle the MSA staff again