The V8 Owners Forum -

Because of the heater pipe which runs underneath my SD1 EFI manifold leaking - again - I'm thinking of fitting a later one which doesn't use this arrangement. I have a 4 litre one from I think a Gems vehicle. Can I use that with my existing trumpet unit and plenum? And would the injectors be ok with a 3.5 - I'm running a MegaSquirt, so am happy to alter the mapping. There are other plumbing and electrical implications, but I think I can work round those.

The GEMS manifold doesn't have a thermostat. On those engines, the thermostat was in the bottom radiator hose. So you might have a challenge to get the cooling system plumbed in.

Chris.

ChrisJC wrote:The GEMS manifold doesn't have a thermostat. On those engines, the thermostat was in the bottom radiator hose. So you might have a challenge to get the cooling system plumbed in.

Chris.

Ah - this one does. (or rather has what appears to be a normal thermostat housing - I've not looked inside) I was assuming it was Gems as the wiring etc is very different from hotwire ones I've seen. The plenum is black - if that helps.
I'm not well up on Rover V8s made after about the mid 80s.

What I was mainly concerned with was if there were internal differences to the manifold - like say port sizes etc that wouldn't suit a 3.5.

Hi

GEMS manifold will take the thermostat, but the holes for injectors are different comparing to early flapper injectors. You might want to convert to later hotwire/GEMS injectors as well.

Cheers

Antti

FinVItesse wrote:Hi

GEMS manifold will take the thermostat, but the holes for injectors are different comparing to early flapper injectors. You might want to convert to later hotwire/GEMS injectors as well.

Cheers

Antti

I have the complete injection system, apart from ECU and AFM. Will the injectors for a 4 litre be ok with a 3.5 - I'm read over large injectors can cause idle problems.

I'm wondering what manifold I have. The casting round about the front end is different from my flapper one - it has a heater pipe which is to the side, rather than rear. I'll do some pics if it helps. It also has a different design of water temp sensor (for the gauge) which looks like the coollant one for the injection. There's also a temperature sensor in the fuel rail.

DaveEFI wrote:

FinVItesse wrote:Hi

GEMS manifold will take the thermostat, but the holes for injectors are different comparing to early flapper injectors. You might want to convert to later hotwire/GEMS injectors as well.

Cheers

Antti

I have the complete injection system, apart from ECU and AFM. Will the injectors for a 4 litre be ok with a 3.5 - I'm read over large injectors can cause idle problems.

Dave those inj's will cause you no problems size wise and they are high impedance like you need for your MS

I've been running low impedance injectors with no resistors for years - using PWM on the MS2. But obviously high impedance would make going sequential easier.

Here's the pics of the 'new' manifold, so perhaps someone could identify the injection and assist as to whether it would be easy to fit to a Vitesse unit - as regards the cooling system. Most other bits I think i can work round.

I am sure the port sizes are the same - they never changed them on the heads when they went to 4.0 / 4.6 litres, so I am sure they never changed the inlet manifold either.

Just check you can actually fit a thermostat inside that housing. So that flexible piece of pipe is the thermostat bypass (connected to the water pump). And the new pipe on the top is the heater feed.

Chris.

So on a gems unit there is still a bolt on thermostat housing - but no thermostat inside? I'll take it off and have a look.

DaveEFI wrote:So on a gems unit there is still a bolt on thermostat housing - but no thermostat inside? I'll take it off and have a look.

That is correct! I don't know if it is machined to take a 'stat.

Chris.