dumping fuel?
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Joined: Oct 2008
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I completely agree with Harte on removing the spacer. Especially if it's an open spacer but even if it's a four hole spacer I would still remove it. Your 300 doesn't rev high enough to see hardly anything but adding it and it's dampening the vacuum your boosters would otherwise be building by completely negating the effects of the split runners of your manifold (if it's an open style anyway), this results in poorer fuel atomization than you would otherwise see. And that's the whole reason you put on that smaller carburetor in the first place.
Running heat to the manifold will prevent carb icing in the winter but it's also for stabilizing the inlet air temperature so your carburetor calibration stays accurate instead of fluctuating with air temp changes. Under perfect tuning conditions warmer air causes power loss but almost nobody runs with perfect tuning.
Putting something together to heat the plenum is a good idea but first thing (I would do anyway, only my humble opinion) is to ditch the spacer.
BTW is it an open spacer or a four hole?
Running heat to the manifold will prevent carb icing in the winter but it's also for stabilizing the inlet air temperature so your carburetor calibration stays accurate instead of fluctuating with air temp changes. Under perfect tuning conditions warmer air causes power loss but almost nobody runs with perfect tuning.
Putting something together to heat the plenum is a good idea but first thing (I would do anyway, only my humble opinion) is to ditch the spacer.
BTW is it an open spacer or a four hole?
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Joined: Dec 2007
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From: Boise, Idaho
i was at the gas station tonight filling up and iv developed this new problem since its been getting colder here in pa, when i come up to a stop light and i press the clutch in and the rpms drop the engine goes super lean to the point where it wants to stall, while refueling i popped the hood and the spacer was ice cold, so im figuring im having some carb icing going on because after you drive the truck for a good 30 mins it doesnt do it as bad. I want to keep the spacer but i am in the process of making a plate for the bottom of the intake to run coolant to. my question is will this be enough because up here it easily gets down to the single digits in the winter and i need this truck to run day in day out. should i also go back to the stock air cleaner and run some drier tubing down to the header to get some heat that way, only problem is iv read about with too much heat you sacrifice power and can end up with a enriched a/f ratio than you would like. i dont want overkill but i dont want to be stallling all the time in the dead of winter
With my setup, the only provision for heat of any kind is the heated spacer. (Also, if it wasn't heated, I wouldn't run a spacer at all.)
Without it, it consistently ran lean at takeoff and bogged a lot. With it, however, I hardly notice the effects of the below freezing, and often single digit, weather we get here in the winter, and it helps to stabilize the tuning in the summer.
Personally, I would think that the heated spacer would be more beneficial than an underside intake warmer, but someone may be able to guide in that better.
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the spacer is the four hole, the spacer increases the velocity of the mixture to the intake valve(s) and it also creates more area due to the increased travel for better fuel mixture, my question is why do guys dislike the spacer, if you think its not helping at all, its certainly not hurting. it runs cold because i have no heat to the intake and my header is wrapped with DEI, when the truck warms it runs good.. i always had the bog while changing gears and giving it gas with or without the spacer.. i believe the real problem is the heat and summit sells a air raid jr intake for the 300 and i plan on extending the air filter element down to the header area to suck in some heat, that along with the bottom heated plate should help me out. i do though like the heated spacer idea, but iv heard you have to jb weld something or you have a big vac leak, does anyone know where to get one or have a link?
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Joined: Dec 2007
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From: Boise, Idaho
Hey 8525ford,
If you want a spacer, and carb heat this is simply the way to go.
FORD 1968 Mustang TORINO FAIRLANE GT 4BL Carb SPACER: eBay Motors (item 180559530615 end time Oct-10-10 20:41:08 PDT)
I usually just type in "Carb spacer" and click "used" and scroll through until I see a picture with noticeable tubes sticking out the sides. I think I've found one almost every time.
Sealing it off is pretty easy. The way I did it was fill the port with JB weld (I put small rocks in it first just to take up some volume, and use less JB weld
) Then let it set up until it doesn't run anymore but is still "gooey" but NOT sticky. Then just press it against something else flat, such as the current spacer you have, and stand on it to flatten it perfectly. Let it dry. And it's filled and no leak.
If you have more money, fill it with JB weld, and then have it planed to smooth flat at a shop.
You also don't need to fill the WHOLE channel, just the part exposed.
Put the spacer in place of your current one and cut the line coming from your heater core and run one side into the spacer, and the other out, and you're done. Spacer and carb heat.
If you want a spacer, and carb heat this is simply the way to go.
FORD 1968 Mustang TORINO FAIRLANE GT 4BL Carb SPACER: eBay Motors (item 180559530615 end time Oct-10-10 20:41:08 PDT)
I usually just type in "Carb spacer" and click "used" and scroll through until I see a picture with noticeable tubes sticking out the sides. I think I've found one almost every time.
Sealing it off is pretty easy. The way I did it was fill the port with JB weld (I put small rocks in it first just to take up some volume, and use less JB weld
) Then let it set up until it doesn't run anymore but is still "gooey" but NOT sticky. Then just press it against something else flat, such as the current spacer you have, and stand on it to flatten it perfectly. Let it dry. And it's filled and no leak.If you have more money, fill it with JB weld, and then have it planed to smooth flat at a shop.
You also don't need to fill the WHOLE channel, just the part exposed.
Put the spacer in place of your current one and cut the line coming from your heater core and run one side into the spacer, and the other out, and you're done. Spacer and carb heat.
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