Air cleaner performance testing

[Keith V]

So i took the ol beast out to test my air cleaner, does it affect performance?
This is a Specter aluminum hat, 1 3/4" gm spacer, 4" flex hose and a duramax filter.
Short answer is no difference
I did 3 1/8 mile, 0 to 50 runs with the air cleaner on, and 2 more with the air cleaner off.
60' times ranged from 2.6 to 3.0
330' times 8.3 to 8.7
1/8 times from13.1 to 13.5
Most of the delta was probably me feathering the throttle to keep wheelspin under control, even on asphalt on a warm summer day with posi, she can light em up!
Keith vasilakes

 

[Richard RV]

An 1.75" spacer...? Do you have a 403 or an engine hatch doghouse?
I have a 3/4" spacer with my 455 and there's definitely not an extra 1" clearance to be had.
Richard

So i took the ol beast out to test my air cleaner, does it affect performance?
This is a Specter aluminum hat, 1 3/4" gm spacer, 4" flex hose and a duramax filter.
Short answer is no difference
I did 3 1/8 mile, 0 to 50 runs with the air cleaner on, and 2 more with the air cleaner off.
60' times ranged from 2.6 to 3.0
330' times 8.3 to 8.7
1/8 times from13.1 to 13.5
Most of the delta was probably me feathering the throttle to keep wheelspin under control, even on asphalt on a warm summer day with posi, she can light em up!
Keith vasilakes

 

[Richard RV]

An 1.75" spacer...? Do you have a 403 or an engine hatch doghouse?
I have a 3/4" spacer with my 455 and there's definitely not an extra 1" clearance to be had.
Richard

So i took the ol beast out to test my air cleaner, does it affect performance?
This is a Specter aluminum hat, 1 3/4" gm spacer, 4" flex hose and a duramax filter.
Short answer is no difference
I did 3 1/8 mile, 0 to 50 runs with the air cleaner on, and 2 more with the air cleaner off.
60' times ranged from 2.6 to 3.0
330' times 8.3 to 8.7
1/8 times from13.1 to 13.5
Most of the delta was probably me feathering the throttle to keep wheelspin under control, even on asphalt on a warm summer day with posi, she can light em up!
Keith vasilakes

 

[Keith V]

um, maybe I mean 3/4" I didn't actually measure it.
Here's a picture of it

"]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner.jpeg[/IMG][/url]
[ http://www.gmcmhphotos.com/photos/data/7303/AirCleaner.jpeg]
And how it fits under the hatch

"]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner2.jpeg[/IMG][/url]
[ http://www.gmcmhphotos.com/photos/data/7303/AirCleaner2.jpeg]
________________________________
From: 'Richard' via GMCMH EFI
Sent: Saturday, July 10, 2021 2:48 PM
To: gmcmh-efi
Subject: Re: [GMCMH-EFI] Air cleaner performance testing
An 1.75" spacer...? Do you have a 403 or an engine hatch doghouse?
I have a 3/4" spacer with my 455 and there's definitely not an extra 1" clearance to be had.
Richard
So i took the ol beast out to test my air cleaner, does it affect performance?
This is a Specter aluminum hat, 1 3/4" gm spacer, 4" flex hose and a duramax filter.
Short answer is no difference
I did 3 1/8 mile, 0 to 50 runs with the air cleaner on, and 2 more with the air cleaner off.
60' times ranged from 2.6 to 3.0
330' times 8.3 to 8.7
1/8 times from13.1 to 13.5
Most of the delta was probably me feathering the throttle to keep wheelspin under control, even on asphalt on a warm summer day with posi, she can light em up!
Keith vasilakes
--


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[Richard RV]

Your spacer is definitely taller than mine. I'll have to revisit the clearance as I'd like a taller spacer to help straighten out the airflow.
I like how you plumbed the nipples on the spacer and bonnet. I have neither of those connections. What line is connected to the spacer nipple?

um, maybe I mean 3/4" I didn't actually measure it.
Here's a picture of it
http://www.gmcmhphotos.com/photos/data/7303/AirCleaner.jpeg"]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner.jpeg]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner.jpeg[/url][/url][/url]

And how it fits under the hatch
http://www.gmcmhphotos.com/photos/data/7303/AirCleaner2.jpeg"]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner2.jpeg]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner2.jpeg[/url][/url][/url]

 

[Keith V]

those spacers were all over the junk yard, there were even some plastic ones if you're into that...
The spacer nipple is fresh air for the vapor canister. I have a new ( junk yard ) vapor canister that has the option of using fresh air.
It's taller but fits in the same bracket. I figure this way a check valve failure won't dump fuel on the ground.
The fresh air breather required bending the tube a little with my map gas torch and I ground the hat thinner so the rubber grommet would fit
________________________________
From: 'Richard' via GMCMH EFI
Sent: Monday, July 12, 2021 11:23 AM
To: gmcmh-efi
Subject: Re: [GMCMH-EFI] Air cleaner performance testing
Your spacer is definitely taller than mine. I'll have to revisit the clearance as I'd like a taller spacer to help straighten out the airflow.
I like how you plumbed the nipples on the spacer and bonnet. I have neither of those connections. What line is connected to the spacer nipple?
um, maybe I mean 3/4" I didn't actually measure it.
Here's a picture of it

"]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner.jpeg[/IMG][/url]
[X]
And how it fits under the hatch

"]http://www.gmcmhphotos.com/photos/data/7303/AirCleaner2.jpeg[/IMG][/url]
[X]
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[MikeB]

Maybe it’s more of an air temperature benefit rather than intake volume. Or
maybe the computer didn’t have enough learning time to adjust increase fuel
to take advantage of increase air volume.