Your donations help keep this valuable resource free and growing. Thank you.
|
Phenolic Spacers |
Post Reply | Page 123 5> |
Author | |
IB Sorgn
Supporter of TheAMCForum Joined: Dec/17/2012 Location: Kentucky Status: Offline Points: 192 |
Post Options
Thanks(0)
Posted: Jun/19/2021 at 6:57pm |
Wanted a way to reduce the heat soak on my carburetor so I decided to give a Phenolic Spacer a try, although I have never read anything concerning their performance. I thought that I would share my findings with you all for what it might be worth. First let me describe my intake setup and the temperatures I recorded before installing the spacer. I run a pretty common setup. My intake manifold is a Edelbrock performer, running a performer series Edelbrock AVS2 carburetor, iron heads, and ceramic coded headers, should that make a difference to some. Ran the motor until I got to a operating temperature of 185 degrees and shot the intake manifold at various areas until I decided that 160 degrees was a good representation. I then shot the carburetor, trying to stay away from the bowls, and got a representation of just a little over 140 degrees. With temperatures dancing around a bit, I decided that a 20 degree difference was as close as I was going to get with this unscientific test. I then removed the carburetor and installed a
1" phenolic spacer sandwiched between to gaskets (cellulose/nitrile/rubber
composites). I then warmed the motor back up to operating temperature and
reshot the same areas with my laser gun and got approximately the same
temperatures for the intake manifold but the carburetor showed a drop of over
20 degrees at 117 with the fuel bowls dancing around 3 degrees cooler. |
|
Madd X
|
|
304-dude
AMC Addicted Joined: Sep/29/2008 Location: Central Illinoi Status: Offline Points: 9081 |
Post Options
Thanks(0)
|
Back in the day I used a MrGasket adjustable multi plate spacer for heat soak. Mostly because it was needed to space my carburator, without fitment limitations with height. Never had heat soak while in Redding CA, where it was 110+ degrees for a week straight.
Yes phenolic spacers work, just winter driving could make icing happen, with todays fuel. A bottle of Heat may help, as i had to use it a few times on my 95 van in Illinois winter weather. |
|
71 Javelin SST body
390 69 crank, 70 block & heads NASCAR SB2 rods & pistons 78 Jeep TH400 w/ 2.76 Low 50/50 Ford-AMC Suspension 79 F150 rear & 8.8 axles Ford Racing 3.25 gears & 9" /w Detroit locker |
|
billd
Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
|
Hmmm, that's exactly what AMC used STOCK on 2 and 4bbl carburetors for years. Think of the 390 with the 4300, or the 290 with the Motorcraft 2bbl. (among others - including 1bbl carburetors)
So AMC and other car makers knew of their effect. "Heat" won't necessarily prevent carburetor icing, problems with water in the fuel and fuel line freezing, yeah - icing occurs because the expanding air below the venturi removes heat from the carburetor, and fuel being atomized, it all results in freezing moisture in the air. Decrease air pressure and the container it's in cools - such as the carburetor throat. When I put headers on my first Javelin I had the throttle stick at about 2,000 RPM one humid fall day - shut it off and dropped the clutch in gear to kill the engine and got out to see the lower half of the carburetor covered in - yeah, ICE droplets and the throttle shaft was frozen solid. This was in the 1970s, pre-ethanol, etc. Fuel line icing - yeah, heat - but then you should buy fuel from a better place and store your car with a fully full and sealed tank to prevent moisture in the fuel. But it will do nothing for real carburetor icing. |
|
Trader
AMC Addicted Joined: May/15/2018 Location: Ontario Status: Offline Points: 6752 |
Post Options
Thanks(0)
|
My first experience with a carburetor icing was in a snow storm. 50 MPH winds and blinding snow. I opened the hood and could only see the top of the breather, the rest was packed snow and ice. Plugged the snorkel with a rag and jammed the heat riser open. 10 minutes to thaw and start, 15 more minutes of hellish drive, do it again and again .... It was a long trip and little in the way of places to stop in 1978 Bruce County Ontario.
The 68 Javelin got me there, finally!
|
|
billd
Moderator Group Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
|
Yeah, up there don't you guys have some interesting snows? |
|
Trader
AMC Addicted Joined: May/15/2018 Location: Ontario Status: Offline Points: 6752 |
Post Options
Thanks(0)
|
Yup, this was one of the roads I was on, just not the year pictured:
|
|
ccowx
AMC Addicted Joined: Nov/03/2010 Location: Yukon Status: Offline Points: 3510 |
Post Options
Thanks(0)
|
Thanks, that is useful information. I do have minor heat soak issues, where the car doesn't want to start for about 5 or 6 seconds of cranking if it shuts down hot and sits for 10 minutes or so. I have long suspected that heat soak and the infamous Holley issues with that are happening. I don't have any spacer at all between my Holley and an R4B intake, due to a Ram air hood.
I unfortunately don't have much room for a full spacer, but I wonder how thick the spacer would actually need to be? Perhaps a 1/8" insulating layer of something would do it? Chris
|
|
Trader
AMC Addicted Joined: May/15/2018 Location: Ontario Status: Offline Points: 6752 |
Post Options
Thanks(0)
|
You need gaskets both sides of a phenolic spacer to seal and phenolic is brittle. 1/8" would crack quite easily. For your case, a single 1/4" nitrile/rubber gasket would be the better option. Edelbrock sells them pre made, but you can buy sheet and make your own.
|
|
Heavy 488
AMC Addicted Joined: Apr/27/2019 Location: In the Status: Offline Points: 3529 |
Post Options
Thanks(0)
|
the factory heat isolator/ gasket is closer to 3/8". Just like the one sold by Edelbrock#9266. They don't need to be over an inch to be effective. It has the grommets on all 4 corners so it can't be over torqued.
|
|
304-dude
AMC Addicted Joined: Sep/29/2008 Location: Central Illinoi Status: Offline Points: 9081 |
Post Options
Thanks(0)
|
Because of the topic, I dug into my stash. For someone who can't have enough spacer, how about a 2" spacer? Mwhahahahahahahahaha!
|
|
71 Javelin SST body
390 69 crank, 70 block & heads NASCAR SB2 rods & pistons 78 Jeep TH400 w/ 2.76 Low 50/50 Ford-AMC Suspension 79 F150 rear & 8.8 axles Ford Racing 3.25 gears & 9" /w Detroit locker |
|
Post Reply | Page 123 5> |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |