Ram Air intake

(Szerző: (), utoljára módosítva: 2007.01.19.)

Well known airbox layout is the socalled ram-air alignment. The efficienty of the combustion in the cylinders can be increased by feeding them with cold air from outside, instead of the hot air residing in the engine compartment. Hot air expands, this way the same volume contains less Oxygene than cold air. (This is why turbocharged engines have intercoolers!) You can apply ram-air to your Lada easily - or not. Check out the following FOUR examples.

1. Bal3 cut a hole on the fender of his 2107.

You need flexible metallic hose (seen on the pictures), diameter is 75mm (3"). The plastic intake scoop was prepared by a friend, but any plastic workshops may do it for you. This intake consists of two parts: the tube between the inner wing and the flexible hose: this can be replaced with the flexible hose itself, of course. The other part is the scoop behind the indicator light (see pictures).

Of course in the winter you also need an automatic cold/hot air switch diaphragm (from a Samara). It will exactly fit your airbox, and it mixes hot/cold air correctly. When it was raining like cats and dogs, I was afraid of getting rain into the carburettor and giving the pistons a hydrostatic shock. I drilled a little hole next to the big intake hole. This smaller hole is in the end of the "scoop", any moisture can spill out there.

2. Tyuiop put Fiat Ritmo grille on the hood of his 2107 - and gave a detailed recipe to you all

You will need the following:
- Fiat Ritmo air intake + grille / or choose any other type /
- Ford injector air filter box / or any matching type /
- flexible large-diameter hose
- 2107-airbox + hot/cold air switch
- hose ties, 2x
- M8 (or equivalent) nut+bolt, 4x
- handtools

First step: if your air filter box is not 2105/2107 type, drop it, and install a 2105/7 type. The 2105/7 and the other airboxes are totally equivalent on the carburettor side, but the 2105/7 has only one (big) air intake. This can be used for attaching the new air hose. Older models had the airbox with two intakes. Other advantage of the 2105/7 type is that the air intake to be used is heading towards the inner wing - just like we want it for this modification.

Next step is to fasten the EFI airbox somehow. This can be done by a sheet metal strip (15-20 cm long, 2 cm wide ~~ 6-8" long, 4/5" wide). Fasten the strip to the bottom of the airbox with bolts and nuts, then bend the strip towards the wing or the battery console. The height of the airbox has to be adjusted exactly to connect to the bonnet (engine bay lid). It should let the lid close 100%. Sounds a bit complicated, but it takes only five minutes to do. If everything is OK, the strip (holding the airbox) can be bolt on the body by self-drilling screws.

Now put some grease (or paint, etc) on the rim of the airbox and close the engine bay lid. Open the lid and there it is - the grease or the paint touched the lid and shown us what to cut out.

The cut has to be made from the outer side, and its diameter has to be smaller than the airbox. Of course the chosen air intake trim has to be bigger than the chosen airbox. You can copy the cutting line from inside to the outside surface as follows: draw 2 diagonals. Their section point is the center of the cirle. Drill it through the lid. Now you have the center point on the outside. Measure the radius of the circle which has been given by the grease or paint traces. Subtract 5mm (1/5"), and draw a circle with this radius on the outside surface of the lid. Take care not to include the lid's strengthening members.

Get the electric saw. Put a sheet metal cutter in it, and cut the circular piece out of the lid. Now put the Fiat Ritmo intake grille over the hole - be sure to avoid the intake's screws being in the way of the front wall when closing the lid!

Mark the position of the screws and drill them. Somehow you have to fit larger screws on the intake than the originals. One way of doing that is to drill matching holes into the M8 bolts, and prepare threads in them - now screw them on the Fiat intake's small bolts. The result: an intake with M8 screws. Fasten the nuts from inside and be sure the intake is correctly attached to the lid. If not, prepare a gasket for it: get an electric cable (matching colour), cut it along, and put it on around the edge of the intake.

The last step: prepare a connection between the 2105/7's airbox (hot/cold air switch) and the EFI airbox. If the hose diameter is larger than the airbox intake diameter, cut the hose in (a few cm's, or half an inch) on 2 or 3 positions, and tighten it with duck tape. Fasten the hose at both end and that's it!

What is this all good for? Heaven only knows!

3. Janusz Mendrala from the Polish Lada Club managed NOT to cut the fender or bonnet

It is a simple cold air inteake. If you look inside, on the left side of the cooler (looking from engine) there is a little more space and I used this to install cold air inteake. I have seen your modifications, but they need some more work and nice painting at the end. In my "design" everything is inside. On the original intake I installed has a thermoregulator from FSO Polonez instead of lada cold/hot switch (it is plugged during summer time). During winter time the cold air is plugged and air temperature is controlled automaticly (in Polonez it is approx. +32 C deg).

This year I also installed a mechanical Weber carburettor from Polonez with biggest available Venturi nozzles (it fit without major problems). The bolts in the inlet manifold must be cut a little and the filter box connection is to be modified). I have sport filter as well. In Poland there is a company producing sport filters, which fits in original Lada box (the some is in FSO 125 and Polonez) and flow resistance is 30-40% lower than in original one.

4. Imre Bóka sent photos only