Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Cold air hose for open K&N

Button, or anyone, can you give more details of the rubber curtain please ? Size, exact location on the cross head and fixing please ? I'd like to try it.

I am planning to make something similar to Craig's car with the addition of the air scoop of Series 1.
At the moment I'm still using the original air filter.
I would like to change it to a K&N but in the original air filter box, or isn't that a good idea?

Dirk, I have the K&N filter mat for the original airbox and it revs more freely up. Before you make more changes than that, the original air pipe is not too bad, it delivers good torque in the mid range. There is a huge cooling water hose below the input of the original box. I have gently bent it out of the way towards the front using two cable ties.

To get the best of the original system remove the 57mm rubber hose which fixes the metal tube to the throttle body. And then remount the tube and have a look and touch with your fingers if the transient is smooth between the tube and the TB and if the angle is correct. The angle can be altered by using more or less washer at the mounting point of the tube. In my case it was about 2mm out of a straight line which causes nasty turbulences at the now existing edges. So I had to widen the hole where the tube is mounted to the intake manifold. This makes really a signifikant difference if the pipe is in line. The engine sounds smoother and low range torque is better.

Do not widen the plastic hole of the intake manifold but the metal hole of the mounting bar which is welded to the tube.

When you dismount this pipe have a look if the output which connects to the TB is round. My pipe was very oval possibly due to inner tension after they welded the pieces of the tube together. I clamped it in a vice and made it round again. A weak part of the original system is in my view the plastic hose which connects the filter box to the metal pipe. It has a 60mm input and a 57mm output. It looks harmless but it is important that it is Very parallel mounted to the metal pipe. At the airbox I have experienced that the engine runs better if you put it also very parallel to the box but leave a space of one or two mm. Just try it which distance gives the best result. The reason, I think is that directly in front of this plastic hose the MAF sensor is mounted and it benefits if the way to the harmonica tube is a small tad longer to avoid turbulences. Since the connection to the TB can better the low rev trque the connection to the airbox can better the will to rev high in a more effortless way. The best would be to replace this plastic tube (which in a Fiesta goes directly from the airbox to the TB) but I have not found a pipe with this dimensions of tapering and angle.

It may sound too pedantic, but the light car thanks you for such small improvements in sum with a nice driving feeling and a bit more agility.

BTW I had mixed results by mounting a hose as an extension to the input of the airbox. The top speed was better when this hose is mounted into the drive direction but the engine revs more freely without it.

Oh sorry, Dirk, now I see you are not talking about the Sigma 4/4...May be someone else who owns a Sigma 4/4 can try out or check what I have described.

The chassis ends dictated the length. The width/height from lower cross tube to upper cross tube dictated the width (I added about 2" to the width. I sourced the rubber mat at the local rubber store this that I used was about 3/16" thick. It can get expensive so I let price dictate quality. I used 2- 1"X1/8" flat bar and sandwiched the top of the rubber mat between the 2 strips of flat bar using 10/24 stainless bolts and nuts. I hung this assy using the rad perches to hole the top into place. I let the bottom remain unattached. I have Gemmer Steering not sure how this would be done with R&P.

Button, a photo would be very helpful if possible.

I hate to admit it but I have never been able to "get to terms" with TM's photo routine.

I sent a PM to Button and he mailed the following 3 photos to me. He writes:

„These are 3 I have in My archives. Looks like they used either plywood or alloy instead of rubber. Not critical, use Your imagination.“

Here are his photos:

Thanks Heinz. Not sure what the two holes are for but suspect they are used to pipe fresh air into the footwell.

I accomplished by drilling a 3" (?) hole in the back of the bonnet and bulkhead and installed a bildge blower to accomplish this. Finished off with Boat Fittings. But I have no problems cutting up My bonnet, I can always sheet metal weld it back together and paint it. Mrs. Button's comfort was paramount.

Dirk,
Have a look at page one. My P4 had an ITG filter as you can see. You could try that.