To re-Snorkel or not?

[MN_Stang]

When I first got my car, I had the engine rebuilt by an older drag racer. He did a great job bringing the stock engine up to easily double the horsepower. In addition to boring/new pistons, he installed a higher performance cam, upgraded to a four barrel carb, added headers and a high rise intake. Once installed, the mechanic said only an 8” open-air air cleaner would fit under the hood vs. the stock larger cleaner within the snorkel.

So my questions are, did losing the larger, snorkel-fed air cleaner take more power away than the high-rise intake added?
What is the basic gain and benefit of a high-rise intake?
Would it be worth reversing back to the lower intake and snorkel (I still have the snorkel enclosure).
Would it be easy to marry the old snorkel with the new four barrel carb? (I’m not totally certain where/how those vacuum lines hook up)
Would a larger low-profile air cleaner be better than my little 8”? -I’ve read that the design of the low profiles can also restrict air flow, so maybe the benefit is a wash.

Appreciate any advice!

[droopie85gt]

I was at test n tune one time with my 85. I ran 6 passes. 3 with the snorkel air cleaner on and 3 with the lid off. There wasn't .2mph difference between any of the runs and the difference was split, so it was a moot point.

People talk about it get cooler air or the open element sucks in hot air. Yeah, at a stand still. Going down the road the air under the hood is all washed around. Probably can't tell a huge difference if you had a thermocouple and tested the temp. Now, if you modified your snorkel inlets to say remove the high beams and pick up ram air there or maybe from the air dam where the fog lights are, you might begin to see some difference above 50mph.

For me it comes down to looks. I like the snorkel.

[homer302]

Must SNORKEL! OEM cold air way back in 1982. It's just too cool. I'm no even casual racer though.

[dagassa]

When I first got my car, I had the engine rebuilt by an older drag racer. He did a great job bringing the stock engine up to easily double the horsepower. In addition to boring/new pistons, he installed a higher performance cam, upgraded to a four barrel carb, added headers and a high rise intake. Once installed, the mechanic said only an 8” open-air air cleaner would fit under the hood vs. the stock larger cleaner within the snorkel.

So my questions are, did losing the larger, snorkel-fed air cleaner take more power away than the high-rise intake added?
What is the basic gain and benefit of a high-rise intake?
Would it be worth reversing back to the lower intake and snorkel (I still have the snorkel enclosure).
Would it be easy to marry the old snorkel with the new four barrel carb? (I’m not totally certain where/how those vacuum lines hook up)
Would a larger low-profile air cleaner be better than my little 8”? -I’ve read that the design of the low profiles can also restrict air flow, so maybe the benefit is a wash.

Appreciate any advice!

If you have Motor Trend on Demand, watch the Engine Masters Air Filter Shootout episode. They test 19 different filters and of the 19, the dual snorkel design is pretty much the worst option you can use! It killed a TON of power versus using no air filter at all. To be fair, it's a bigger motor but still, the results were eye opening!

[devittjl]

When I dynoed my 82 Capri RS (crate 306) headers I was getting a major air flow restriction at high rpm with the snorkel. We did the last pull with the top of the air clearner removed and added 10HP to the top end!

[gr79]

Do both.
Stock dual for everyday driving. Looks good. Dresses up engine look. Can hide mods to some extent. Base sits low over carb.
Track- Common to bring along parts for race duty. Fresh element for track only. All open, or taller element for stock dual.
High rise manifolds a key component for adding power and or torque. Best results when matched correctly with other mods.
But they take away vertical space for tall air filters.
Benefit of open element is easy to adjust filter height to tallest one that clears hood with lid on.

Stock snorkel should fit on new carb. Usually std hole size. Hoses are mainly for emissions, v/c breather, hot air doors.
Air flow in low profile air cleaners bends sharply over the top of carb due to the low height of top cover above carb venturis.
The ones that sit flat on top of carb with short elements. Need room over top of carb for air to move easy as possible.
A base that fits down on the carb, not on top, sort of adds a 'stack' to help smooth out air flow above carb. Straighter flow is better.
Smooth flow is best for max power. Another area where air flow adds or subtracts some power. A little here and there adds up.
Plenty of muscle cars had 'restrictive air cleaners' but were fast. Some did have chrome open element that looked cool (Chevy, some Ford).
Some factory ram air setups and scoops did add some power but most were mainly for looks.

[Matt J]

Keep in mind that if you remove the filter completely, of course it's going to flow better. That's fine on a dyno, but if you're going to drive it you'll need to run a filter, and I'd expect the stock filter to not flow as well as one designed for racing. The only purpose of the snorkels was, at least in theory, to draw cooler air from outside the engine compartment, which it does. It was also designed for engines that topped out at I believe 210 HP in 1985, and the numbers I always hear thrown around the forum is 10-15 HP gained by doing this. No clue if that's real or not, but K&N has made a living with cold air intakes, and pretty much every car has a cold air intake on it now (probably because there isn't room under the hood for an old school filter anymore, but there must be something to it).

How this impacts a high performance engine making 400HP, I don't know, but we can agree that the dual snorkel wasn't built with the intention of flowing that kind of air through it. I'd guess the limiting factor is the size of the filter not the snorkels themselves. So what I'd say is that for the average roughly stock setup the snorkels help, but for high performance ones most likely not unless you can modify it to fit a wider filter, which then probably wouldn't fit under the hood.

Either way, I think we all agree it's cool...

[erratic50]

The discussion with air cleaners should focus on CFM. You can make massive power at lower RPM but run out of air up high, etc.

[mudgepondexpress]

The question to me is easy... are you going to set up ram air? Cool Air? Or are you just going to let the snorkles dangle? Unless you are setting up a ram air system (hopefully a little better than stock cold air system), go with the snorkles... if not, the biggest open air cleaner you can fit.

As an aside, I do like them to look stock, but run much, much better... the sleeper syndrome.

Kenny

[homer302]

People that are comparing tests of other cars have little to do with yours. I also watched a 306 on a dyno and it had an open element (non snorkel) air cleaner on it. It gained 14 HP with a SOLID metal lid over a K&N filter lid (do they even still make those?) with a Mighty Demon carb. Does that mean anything to you? No, of course not. You have to be strapped down to the lie detector and even then, as someone above mentioned, driving down the road even the results may differ. Test results of some other combination...ANY other combination other than yours are maybe not useless but are merely a guide or suggestion at best.

[78futura]

My futura has a single snorkel and a very small like 1 1/2" paper element. Not sure what to do.. without cutting the hood.. prob best bet is do a ram air with the high beams out... at least a big scoop won't give it away... factory hubcaps and hood ornament help. Lol

[bwguardian]

The op didn't state what year Stang he has...but the statement: "upgraded to a four barrel carb," tells me it may be an 82. On my ole 82 GT of years past, I took the end of the snorkel pipes inside the fender wells and connected them up to the outer air scoops in the factory front spoiler. There was a noticeable difference at highway speeds but that was about it. K&N also made a black air transition stubstack that went down over the filter housing base which the filter lid stud secured it and smoothed out the air flow into the venturies...I had one of these on my 82. Here is what it looks like: https://www.knfilters.com/racing/stubstacks.htm The 82 dual snorkel filter housing utilizes a smaller filter as compared to the late 83 to 85 models.

On my now 85 GT vert I have a K&N filter element in the stock dual snorkel filter housing, on top of a stock four barrel carb, on top of a plastic 1" open phenolic spacer, on top of a Ford Racing high rise dual plane intake manifold. This all fits under the hood even with the stock hood insulation with no issues. It does so because the convertible engine mounts are not only stronger that the regular ones...but they are also shorter, thus lowering the engine in the engine bay a bit. So if you don't have the clearance, you may think about changing out the motor mounts to the vert style for more clearance.

[78futura]

The op didn't state what year Stang he has...but the statement: "upgraded to a four barrel carb," tells me it may be an 82. On my ole 82 GT of years past, I took the end of the snorkel pipes inside the fender wells and connected them up to the outer air scoops in the factory front spoiler. There was a noticeable difference at highway speeds but that was about it. K&N also made a black air transition stubstack that went down over the filter housing base which the filter lid stud secured it and smoothed out the air flow into the venturies...I had one of these on my 82. Here is what it looks like: https://www.knfilters.com/racing/stubstacks.htm The 82 dual snorkel filter housing utilizes a smaller filter as compared to the late 83 to 85 models.

On my now 85 GT vert I have a K&N filter element in the stock dual snorkel filter housing, on top of a stock four barrel carb, on top of a plastic 1" open phenolic spacer, on top of a Ford Racing high rise dual plane intake manifold. This all fits under the hood even with the stock hood insulation with no issues. It does so because the convertible engine mounts are not only stronger that the regular ones...but they are also shorter, thus lowering the engine in the engine bay a bit. So if you don't have the clearance, you may think about changing out the motor mounts to the vert style for more clearance.

Yeah thats what I put in too the vert mounts. With the air gap it is very tight. I have no spacer over the carb. I think i have an inch and a half clearance...

[brianj]

I made the hood scoop functional, just for this reason. It gained me over 2"of room for a filter.

[78futura]

Anyone ever use or know it you can use a factory fod air cleaner housing like a dual snorkel and add a
K an n power top lid dealio? Would be a great way to add cfm and still get some cool air and also use a pcv from a valvecover all in one shot!

[emerygt350]

In mine it wouldn't matter since it pretty much rests against the sound deadening material.

[homer302]

Anyone ever use or know it you can use a factory fod air cleaner housing like a dual snorkel and add a
K an n power top lid dealio? Would be a great way to add cfm and still get some cool air and also use a pcv from a valvecover all in one shot!

I watched a Cobra kit car strapped down to a dyno on back to back runs GAIN 14 HP by swapping out one of those K&N lids for a solid steel one. That is irrelevant for your car though. Just information for thought. The K&N lid would fit but it would only cover the diameter of the air filter, not the whole housing. Which may or may not be a good or bad thing. You'd have to run a back to back test to see for sure. They don't make a lid as large as the OEM lid is. It just covers the filter.