question on phenolic spacers

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pjc360

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I bought a 1 inch phenolic caruretor spacer to put on my 360 magnum because the engine was showing symptoms of vapor lock, hving a hard time firing after been running for awhile and the fuel was extremley warm when exiting the carburetor. Anyways i put the spacer on tonight and started the engine just to make sure there was no leaks and that it would fire up, didnt get a chance to take it for a drive tho. My question is will this 1 inch spacer rob power from me? or will it benefit me by increasing power? and if so do spacers help incease torque? or horsepower? i thought i have heard tht carb spacers add torque, but aint 100 percent. Or i it robs power from me, does it rob horsepower or torque? because if it aint worth having on i will take it off, i was just looking for a way to help keep the carburetor cool and the fuel cool and hopefully gain a little moe power during the proscess.
 
Is it a 4 hole spacer or an open spacer? I have heard that a 4 hole helps torque and an open spacer helps hp.
 
Haven't used spacers on a Mopar SB. But have when I was building SB Chevy's (sorry guys & gals :geek:) more for strip oriented than street builds. Typically I found low end power to dip a bit, but picked it up on the top end. But on a strong running motor I found the low end losses negligible. Being a very simply mod, you may just want to give it a try and see how it works for your application.

Pat
 
It's a 4 hole 1 inch phenolic spacer, main reason i put it on is to try ns keep the fuel cool, because obviously the cooler the fuel the better its gonna burn. I hve heard it both ways as well, i hve heard the spacers add low and mid range torque and then i have heard they rob low end torque and give hp up high in the rpms. But i have herd of them adding low to mid range torque from more people then having heard they rob torque.
 
I put an open one inch spacer on my 318. I have less torque now and I no longer fry the tires off the line. It also gave me more horsepower because it pulled my mile per hour in the quarter mile over 100. It was a win situation at both ends of the track.
 
Soi should ditch the spacer? i certanly ccan not afford to lose any torque at all because my engine is in a 4 wheel drive truck. I had always heard they had torque but who really knows untill you throw it on the dyno right? i guess i will go run it and see how it is and then run it with it off and see how it is and hopefully i can tell a difference.
 
And i have heard its open hole for the single plane intake and 4 hole for the dual planes lol, i wish somebody would come clear up this carbuetor spacer debate and answer if it robs power or provides more and where, i'm sure somone on this site knows.
 
pjc360 said:
... answer if it robs power or provides more and where, i'm sure somone on this site knows.
Click to expand...
I don't know how anyone could answer that without very careful double-blind dyno tests, and who would pay for that? I work in aerospace testing and we don't have funding to study things to the nth degree. I suspect a 1" spacer would have negligible effect on air flow and atomization of the fuel. The main thing is insuring you maintain the carburetor to intake match, such as having a 4 hole spacer if a dual plane intake.

There certainly are intake effects, such as the long runners in most current production engines (or even Mopar's early 60's Ramchargers) for better mid-range torque, or the long tall plenums in after-market intakes for high rpm. However, do you really think 1" is noticeable? Anyone who says they notice a big difference, treat as "hearsay".
 
I have seen dyno sheets on a mopar and with adding a 4 hole phenolic carburetor spacer to a dual plane intake they gained 5 more horse power and 5 more ft lbs of torque. This was on a 408 stroker mopar engine. I guess it truely dpends on the engine and the intake and the carbuetor. I have a 300hp 375 ft lbs of torque engine wich is way under rated by mopar by the way... I read an article in a magazine where they got a 300hp 375 ft lbs of torque 360 magnum and all they did was add headers and a mopar m1 dual plane intake manifold with a demon 750 cfm carburetor and an msd ignition and they threw it on the dyno and it was putting out 319hp and 424 ft lbs of torque. I have headers on mine along with a dual plane edelbrock rpm air gap intake manifold and a 600cfm edelbrock manual choke carburetor and the mopar electronic distributer with vaccume advance. This is the set up i am running a 1 inch phenolic carb spacer on, and i am not running it to gain huge amounts of power, the main reason i decided i'd give a spacer a try is to keep the carburetor cooler (throttle plates) mainly and to keep the fuel cooler, and if running the phenolic spacer provides more power at the same time then thats great, thats all im trying to find out. And if it robs more power then its worth then i will take it off and find another way to keep the carb and fuel cooler. Thats why i posted this question, just trying to learn about it.
 
By the way i just put the 1 inch phenolic spacer on it tonight, didn't get the chance to go run it and find out. And this engine is in my 1991 dodge power ram 150 that is 4x4, thats another main reason i am asking about the spacer providing power or stealing it, because i can not afford to lose any torque at all.
 
I have a 1" Open Spacer under the 850 TQ on the 340 in my '74 Duster. Seems a little "hotter" on take off, and picked up some better throttle response. Butt-Dyno measurements :D 3.23's and 28x10-14" tires. I can burn the tires for a block (or until the next redlight, whichever comes first). I try not to though, 14" tires are getting hard to find.

and I've got a 1/2" Open Spacer on my '84 Dodge D50, with a 273 and a 800 TQ. Couldn't run a 1" because my filter almost rubs the hood at the moment. That baby will spin the tires like you wouldn't believe... 4.10's and 40x17-15" tires.
 
So the 4 hole spacer adds low end torque and better throttle response? and the open spacers add more hih end power?
 
4 hole, open, I dunno I haven't read anything disseminating the differences other than right now. I have read however that running a spacer will increase low end torque. I plan on running one myself, and will judge by the butt dyno, if I don't like it I'll pull it.
 
I just read an article by a man who does intakes that the phenolic spacers do cool the carburetor for a denser charge and does cool the fuel as well. The open spacers add high rpm horsepower and take away low end torque and mid range torque therefore open spacers are better suited to be ran on single plane manifolds. The 4 hole phenolic spacers increase low end and mid range torque by allowing my air to come thru the intake and it also allows the fuel to burn evenly in the intake.
Thats not what it said word for word but in a nut shell thats what it said about the phenolic carb spacers.
 
Running it on the dyno is just about the only way to see how it likes it.
Having said that, most big HP engines run spacers in the dyno competitions.
Definately run some kind of heat insulator spacer with an Eddy carb. They are known for heat/fuel issues. Either way your on the right path for cooling the carb/fuel.
I run a Edelbrock #9266 heat insulator with my Eddy carb and Eddy RPM intake. Works well.
 
Stop and think about this: You have a cam with overlap. The intake valve opens while the piston is not quite to TDC, helping the exhaust flow out the exhaust. Does any exhaust get in the intake? Probably not.

Do pulses from other cylinders affect flow at times? No one knows. Does slamming the exhaust shut, stopping the exhaust flow affect the incoming charge? Maybe. This changes the flow for a split second, maybe, affecting the signal to the carb. Times 8.

No, this is what I have been told, by an ex-racer and machinist that has shelves lined with NHRA trophies for national record holder.

Nobody knows what convoluted stuff is happening in the intake manifold. So if you use a spacer, you get the carb out of that mess, which keeps it from sensing the rock and roll going on. It feels a constant need for flow.

Any spacer good. 4 hole for bottom and mid; open for top end. He says he learned that just getting the carb up of the intake stabilized the signal.


Hope I explained it right, probably not.
 
You did, i understand more about the spacers now, i think i made the right choice concerning a spacer for my application, a 360 magnum in a 4x4. i got the 1 inch 4 hole spacer wich will add o low and mid range torque and i got the phenolic spacer wich will help cool the throttle plates on the carburetor among other parts of the carburetor and it will keep the fuel cooler.
 
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