Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) 4/4 Sigma 1600 Sports manifold and cat.

I tried something. One result is that even without the long tube at the 4/4 to the filter box a good torque at low speeds is achievable. A second result is that the open filter works better at high revs.
The position under the windshield is the best, but it is quite loud at full throttle.




The position to the side of the intake manifold is more tolerable. The car still drives very well but it is warmer and has a low pressure zone. But an air pipe to be added could help in the future.



Since I am overwhelmed from today how well my new gas pedal works I will install the standard air box again out of interest. At least on long journeys the sound of the open air filter annoys me a bit. I have to say that the standard airbox is not as stupidly positioned as you might think. Cold air is scooped up from under the car, even more since I have the bigger Mulfab aluminium radiator.

On the other hand, the air above the engine warms up unnecessarily in the long standard tube.
What I would like to recommend to all people, whatever you do, please reconnect the crankcase ventilation. The engine runs fuller and sounds rounder. The fuel consumption is significantly lower. The Sigma has this inlet in front of the maf sensor, so I did it in this order.

Pleased to hear that Heinz has the running issue sorted with a new throttle pedal. That's one for future reference.

Regarding cold air being scooped up from under the car ( original air box) I have modified mine to obtain a "ram-air" effect. Works really well.



The scoop is in direct line to the flow under the car and seems to work really well. I have since added a mesh grill to keep leaves etc from being sucked in.




A flexi pipe then ducts upto the original air box ( with K and N) filter installed. Air scoop was under £20 and the pipe was £7.99 so a really cost effective job.


I still have the long air pipe along the top so I may well experiment along the lines of Heinz in the future - I however understand Cain @ Wolf performance is working on an air - intake system so will likely see what he comes up with first.

I though Cain had disappeared off the planet ?

andymot, your scoop looks really well, it looks like a PA sound system horn tweeter:)
I had tried a similar configuration but just with a pipe connected to the filter box and without the scoop. My impression was regarding my try without the scoop that the car revs a bit more freely without the additional pipe but she is significantly faster at higher speeds in 5th gear with the pipe introduced..

Can you tell me where to purchase the scoop?
For the future I could think about a long pipe to the TB which is not longer than the original one but it could possibly run at the side of the engine near the intake manifold and not above the engine.

Anyway I believe that the cold air from down and then streaming up is more efficient than air from above the radiator.

Don't go through any deep puddles or drive when there is a lot of spray

Heinz - the scoop came via Cain @ Wolf performance.

A similar one is on ebay here -

https://www.ebay.co.uk/itm/Air-Funnel-Kit-Car-Styling-Auto-Front-Bumper-Universal-Lightweight-Intake-Pipe/133079607676?hash=item1efc29a97c:g:mIgAAOSwQXtc~XEV

Cain may have another the same as mine laying around? - best drop him an email

www.wolfperformance.co.uk

That‘s my concern Keith. TB very H now after the system is ok again with the new gas pedal, a remapped ECU, a sports manifold I will just install the original airbox because it is at a more moderate sound level. I cannot transform a 4/4 into a Ferrari. So this stage of altering as it is will be sufficient and I‘m happy with it.