The V8 Owners Forum -

Opened a can of beer, sat on my spare block and looked at the almost-complete engine until the can was empty, and still couldn't figure the cooling system plumbing out for my RV8! NB I am not using a heater system; track car only. Also when I say 'right' or 'left' I mean as you look head on at the front of the engine. The main problem is I don't know the flow directions, esp. for the header tank etc.

Mine is a bit of a wierd system so bare with me, I'll try and cover everything;

1. Standard MGB V8 radiator: top hose (inlet), bottom hose (outlet) and a small connection right next to the top hose (is this overflow? Outlet or inlet?)

2. Header tank with a single small connection at the top (inlet?), and a larger connection at the bottom (outlet? To where?). The top connection is attached to the small connection on the rad, and also Tee'd with the small outlet on the right side of the inlet manifold. I assume that the top connection from the swirl pot should also be connected into this?

3. Custom swirl pot which is mounted directly where the thermostat is. This has an outlet on the side at the top (which goes to the rad top hose), a small outlet on the top (assume air release - goes to top of header tank), and a third connection near the bottom of the tank (outlet, but to where?!).

4. Vitesse timing cover, with large inlet from bottom of rad and two connections at the top of the pump. The right-hand of the two is currently connected to the inlet on the manifold. I don't know where the left one goes or whether it is inlet or outlet.

5. Hotwire Injection Manifold. Most of connections covered above, except from what looks like a bypass connection on the left hand side, just behind the 'stat. Now, does this connect to the left hand connection on the top of the pump?


So, the problem is plumbing in the outlet from the bottom of the header tank, the 'bypass' on the inlet manifold behind the 'stat, the left hand connection on top of the pump, and the lower outlet at the base of the swirl pot.

All very confusing I'm afraid! Google is no help.

On Tony's Capri V8 site it does appear as though the inlet manifold 'bypass' has a blanking plug? If so, then can I connect the header tank outlet to the left-hand water pump connection?

That would just leave the swirl pot connection - which could also be blanked off.

Finally - where is the best place for my Laminova heat exchanger to go (can't find any info on this whatsoever!)

Many, many thanks if you've read through this and understood it. More thanks if ya can help!

Sounds like you have a swirl tank which is designed to run in parallel with the radiator i.e. input from the top hose outlet to the bottom hose. It sounds as if you have lots of other small degas lines feeding into the swirl tank, you can connect as much stuff as you like into this. You should have two inlets to the top of the pump, one is the heater return (fed off the back of the inlet manifold and returned through a metal pipe under it) and the other the bypass from the front of he inlet manifold. Make sure you keep the bypass - what you do with the heater supply/return is up to you.

The other common addition is a small spigot on the top of the inlet manifold which feeds the throttle body heater, the return tees into the heater return pipe. This is best left disconnected i.e. blank off the small hoses or simply connect them to each other, so that the throttle body heater is left disconnected.

Cheers for the reply

So, I could take the outlet from the bottom of the header tank and return that to the pump (left hand side heater return connection). I might plumb in the Laminova on that line as well.

As for the other connection at the base of the swirl pot - still clueless lol! Prob best blanking that off to be honest, it jsut complecates things!

Will try and get some photos of everything over the weekend and stick them in my garage section.