1974 Air Cleaner and Carb Question

[scgstuff]

[Backstory]
We are in the process of trying to remove the starter on my son's '74. That third bolt I think will be the death of me. I have read all the posts here and tried the U-joints and extensions, etc. but still haven't been able to get the darned thing off.

Well, since it is giving us so much frustration, I figured I would get a gear reduction starter to replace it with regardless of whether it is the problem part. I know the gr starter is a bolt on, so no changes needed. Well, when we were on the page to order it (http://www.allisonsautomotive.com/products.html#engine), we noticed an air cleaner right above it he really likes.
[/Backstory]

So, I have a few question.....

• I see the '74 listed as having a 34 DMSA carb standard. I have not checked to verify that is what is still on there, but assuming it is, will the 32/36 work? Or do I need to find a different one?
• Would this be a simple bolt on part?
• Are there any other mods that need to be done with changing the air cleaner? I haven't planned on doing anything with the carbs right now. Will they need different size jets installed? (If so, he will probably need to wait.)
• After new air cleaner is installed, will there be any noticeable difference with the engine, or is it mostly a cosmetic enhancement?

[So Cal Mark]

the base of the air cleaner will need some trimming to fit the air horn on your stock carb. As for any difference, you will hear a difference. The "lunchbox" air cleaner has more surface area than the snorkel on your stock air cleaner, so the engine should breath easier

[scgstuff]

the base of the air cleaner will need some trimming to fit the air horn on your stock carb. As for any difference, you will hear a difference. The "lunchbox" air cleaner has more surface area than the snorkel on your stock air cleaner, so the engine should breath easier

Thanks! So no need to re-jet or anything with it breathing easier? That is what I was hoping to hear. Didn't want to introduce too much air and lean it out, but didn't know if it was enough of a difference.

[bradartigue]

I have found that the stock air cleaners are restrictive even with the stock carburetors, and much worse with the larger carbs. Whether you put on the DFEV or not, ditch that air cleaner assembly. It's hard to work on anything with it on there anyway.

The stock carb on a 74 is a DMS. If you have one consider sending it to a competent rebuilder as opposed to replacing it with a DFEV. The DMS is a workhorse, the last power carburetor ever installed on a Spider. I'm not sure a DFEV would be an upgrade, except that it would be new and may perform better because it is clean and tight vs. an old DMS.

[btoran]

brad - what air filter upgrade would you recommend for my 1975?

[124Germ]

I have the same question about air cleaners, but I have a 72 1608 with a DHSA (I think) and curious what cleaner would help out the best.

I have seen the short and tall "lunch box" style from Auto Ricambi, but now sure which would fit under the stock hood.

Thanks

[Dougieb]

I have a '72 with a DMSA carb on it.
I have an extra air cleaner assembly laying around... (who doesn't? ha ha)
I am considering taking one and drilling a bunch of holes around the sides to let it "breathe easier" but keeping
a quasi-original look.

Has anyone done that?
Did it work?

Thanks

[majicwrench]

Sure lots of people drill em full of holes. Are they really restrictive??? Why would the fiat engineers make a restrictive air clearner?? They work fine stock, and only somebody with a dyno could tell you if changing air filter housing actually improved anything other than making it noisier.The roar tend to make people think they are going faster.
Keith

[bradartigue]

Sure lots of people drill em full of holes. Are they really restrictive??? Why would the fiat engineers make a restrictive air clearner?? They work fine stock, and only somebody with a dyno could tell you if changing air filter housing actually improved anything other than making it noisier.The roar tend to make people think they are going faster.
Keith

I would agree that the roar makes people think they go faster, but they are pretty restrictive air cleaners. I always felt the foam type air cleaner that the Weber dealers sell was fine, and pretty cheap, and so was the "meaner cleaner" or whatever the old Bayless model is.

You can feel the difference in the top air, at max air requirements (WOT), but below that not really.

If you really want to hear a lot of noise that generates a disappointment in terms of actual power, put IDFs on your car.

[majicwrench]

I've always figured there must be a good reason (one that eludes me) for having somewhat restrictive air cleaner housings. Look at old chevys....396ci, and the air cleaner snorkel is about 1" ID.
I do have pretty strong faith in the engineers that built our cars, and if they gave it an air cleaner with a snorkel that was somewhat restrictive, they must have had a good reason to do so. If they could have opened up the air cleaner and got a few more HP, they would have done so. But they didn't. Hmmmm.

Keith

[bradartigue]

I've always figured there must be a good reason (one that eludes me) for having somewhat restrictive air cleaner housings. Look at old chevys....396ci, and the air cleaner snorkel is about 1" ID.
I do have pretty strong faith in the engineers that built our cars, and if they gave it an air cleaner with a snorkel that was somewhat restrictive, they must have had a good reason to do so. If they could have opened up the air cleaner and got a few more HP, they would have done so. But they didn't. Hmmmm.

Keith

Well that could be said about any car, and I don't think the decisions have much to do with engineering so much as reliability. A fully exposed air cleaner gets nasty quick on a daily driver, and (on a Spider) a high filter hits the hood bottom, so you have some issues. If it was purely up to the engineers the air cleaner would likely be omitted, as any such device creates a restriction that impedes maximum performance. For a FIAT engineer you probably had to either leave the thing off or take whatever part fit every other model, which is more or less what they did.

There is no nirvana though; the "free flowing" types have absolutely no chance of getting cooler air than whats in the engine bay, while the OEs did at least point in the right direction. And on a cold day the OEs could pull from directly over the exhaust manifold.

And what fun would it be if they did? We wouldn't have things called "Meaner Cleaner" and guys would be talking Fram parts. Yawn..