Cold Air Intake/filter!

Lowtechprime

True Classic
I didn't want to just suck in hot underhood air into the carb and this is what I've come up with.. After looking at how the heater pulls in air from the hood, I thought I could adapt a heater box on the other unused vent on the driver side but ultimately the box was too tall to use as is, + I needed an air filter that won't get wet in the rain. I got a Saab 9000 filter box at the pick a part, (It looked to be the right size/shape+I could get a flat K&N element for it) I thought I could use ABS glue but both boxes seem to be a more waxy, polypropylene type of plastic so adhesive wouldn't work. I ended up using a heat gun with a focusing tip and I plastic welded the two boxes together. It's super strong, airtight, and even looks fairly factory. I cut down the Fiat heater box and made a new top rain tray on the computer and had it 3d printed.(the tray in the pics is a cheap Low res print for testing, final one is on the way) Then it gets the rubber seal around the top edge to seal against the hood...
 

Attachments

  • IMG_20210712_191830008.jpg
    IMG_20210712_191830008.jpg
    564.3 KB · Views: 72
  • IMG_20210712_191902296.jpg
    IMG_20210712_191902296.jpg
    560.1 KB · Views: 71
  • IMG_20210712_191814636.jpg
    IMG_20210712_191814636.jpg
    543.2 KB · Views: 71

kmead

Glutton for punishment
That was a great idea. The next time you have it apart could you take pics of the parts that make this up?

I presume it has a water drain somewhere down in there?
 

Lowtechprime

True Classic
Yes, the front part is the 128 heater box so there's a drain in the bottom. Will take some pics later on today of the assembly..
 

ernie42

Daily Driver
On my RHD I wanted a cold air ram intake but wanted to still have the tyre in the engine bay so I went the forward route. Squared up the round opening in the front panel. Made a enclosure for a K&N out of 3mm sign-writers PVC sheet . Like you ,finding the right plastic was a hassle- cheap super glue welds this stuff in about 5secs. Once I found a fiat carb Hat I think it looks pretty stock
 

Attachments

  • aug3w.jpg
    aug3w.jpg
    186.6 KB · Views: 37
  • engine_bay_13.jpg
    engine_bay_13.jpg
    285.9 KB · Views: 37
  • P1070137.jpg
    P1070137.jpg
    219.3 KB · Views: 38
  • PW1219.JPG
    PW1219.JPG
    207.5 KB · Views: 36

kmead

Glutton for punishment
On my RHD I wanted a cold air ram intake but wanted to still have the tyre in the engine bay so I went the forward route. Squared up the round opening in the front panel. Made a enclosure for a K&N out of 3mm sign-writers PVC sheet . Like you ,finding the right plastic was a hassle- cheap super glue welds this stuff in about 5secs. Once I found a fiat carb Hat I think it looks pretty stock
You might consider a water baffle/stand off plate to keep a rogue amount of water from going right up the tube, I know it is a steep hill you have there up to the actual carb.

It would be better for the air cleaner as well to reduce bugs etc being driven right into it.

A box behind the front opening with the filter on top of the box and a 90° to the carb top would work well. Just a thought.
 

ernie42

Daily Driver
I have been running it for about 5 years now with no water ingress ( and thats in wet NZ) .
Have checked the filter yearly and cleaned it once -even though it didn't need it and thats with a lot of gravel rd driving-
A 90 degree angle defeats the purpose of a ram air feed. I am running a modded engine so the more air the better.
Also the structure I have made is utilising the most space available any more construction and it would need to be removed each time to check plugs etc
 

Lowtechprime

True Classic
Nice! I like the ram air idea but I've run into problems before on my Datsun with the ram effect pressurizing the airbox and I was getting weird carb fluctuations.. Those are bike carbs though.. Also though, what else was I gonna do with all that empty space where the tire was? That's got to be the worst feature of the 128. It's already nose heavy, has a large rear trunk, and that engine heat can't be any good for that tire...
 

ernie42

Daily Driver
Yes I agree wish they had put the spare in the rear. I was wondering what carb you are using and how did you deal with the engine vapour pipe that usually goes to the air cleaner?
 

Lowtechprime

True Classic
Yes I agree wish they had put the spare in the rear. I was wondering what carb you are using and how did you deal with the engine vapour pipe that usually goes to the air cleaner?
34 DTMR... Do you mean the crankcase vent hose? It's now just venting to atmosphere, under the car..
 

carl

True Classic
In that case, I'd put the end of the breather right next to the chassis under the battery box.
 

Lowtechprime

True Classic
In that case, I'd put the end of the breather right next to the chassis under the battery box.
My car had the battery box removed, and the battery relocated to the trunk.. The battery only weighs 5lb, so it doesn't redistribute any real weight to the rear, but it does remove 45 or so lbs from the front..😁
 

carl

True Classic
What I was referring to was the usual heavy rust directly under the battery which can really trash the frame rail, inner fender and sway bar mount. I too moved the battery to the back on all my 128s.
 

Lowtechprime

True Classic
Here is the final! The paper element gets replaced by a K&N filter. I still need to paint it and I was going to put some insulation on the front to keep the hot radiator exhaust off it...
 

Attachments

  • IMG_20210906_160655377_HDR~2.jpg
    IMG_20210906_160655377_HDR~2.jpg
    341.1 KB · Views: 23
  • IMG_20210906_160542516_HDR~2.jpg
    IMG_20210906_160542516_HDR~2.jpg
    354.9 KB · Views: 23
  • IMG_20210906_181906508~2.jpg
    IMG_20210906_181906508~2.jpg
    250.2 KB · Views: 22
  • IMG_20210906_181822828~2.jpg
    IMG_20210906_181822828~2.jpg
    290.7 KB · Views: 22
Top