Yep... fit and forget. Shape and angle of the tank, position of the fill neck & vent pipe, position of the outlet, position of the sender, fuel lines and type of fuel pump all make a difference to whether it may or may not be an issue. No need to for luck if you fit baffles in the tank.
The latest in HAMB topic response, go from a hot rod gas tank to surge tanks, tankers, foam, blip blop science and deep technology. "Mine never had one so you don't need it!" "Mine did so you do!" "Less filling!" "Tastes great!" Simple 16gal hot rod tank, is it a long skinny? Baffle it. If that shit can slosh side to side in a 30" wide tank I'd hate to be ½ tank on my skinny Firestones hitting freeway cloverleaf in the rain at any speed above 30. Even a single baffle cuts the momentary forces in half. Just because some get away with it doesnt make them a waste of effort, if there's an opportunity then do it. We don't need to know anything else. What harm is there? Given a choice I'm in the baffle line. And if that simple act is gonna make or break the project then you should build bicycles.
Some of the original factory engineers said they were needed, some said they weren’t. Take sides with whichever engineer you agree with and do or don’t put them in.
If nothing else, they give you a place to clamp the tank down tight with out crushing it, just as shown by oj above.
When it comes to debating baffles, I think there are a some considerations that come into play. Is the tank nearer the center or hanging off the back of the car? The shape of the tank and how that shape is oriented in the car. What percentage of the weight of the car is the weight of the fuel?
Which begs the question why would anyone design tank mounts so poorly that they'd be capable of " crushing" the tank ?
The way I look at it, if I'm fabbing a tank it will have baffles, if it's a stock tank, going into stock type position into a stock type vehicle then no problem with no baffles. If I plan on building something that will generate some good horsepower into a vehicle that will see some hard cornering or hard acceleration and/or braking then yep baffles can't hurt, especially if it's going to be mounted vertically. Had a 67 chevy truck with the behind the seat gas tank and I drive it hard, with 327 and 4:88 posi doing donuts you definitely could feel the gas banging back and forth across that gas tank. ..
Ever wonder how long your engine runs if the fuel supply is not sucking gas? In most cars a very long time, even if you're accelerating! So why would an occasional slosh make your carbs or engine starve of fuel? I've started my car up and forgotten to turn the electric fuel pump on. Revved it up a little and put it in gear, and gotten a couple blocks down the street before it begins to stumble, and I quickly flip the fuel pump switch on. If I can go that much time with a well built V8 and dual Holley carbs, I sure don't think even a few seconds of exposing the fuel outlet from no fuel is going to even make a blip I'd know about. That's the reality fellas, and you can turn off your gas lines and see just how long it takes to begin stumbling.
What you say is for the most part probably true, but something you should consider is that with an "in tank" electric fuel pump, if your fuel continually sloshes away from the pump it will be running dry for short periods of time which will eventually result in more wear and possibly early failure. Also in an acceleration situation, that could mean no pressure if someone is running fuel injection. With a carb there would still be fuel in the bowl till the pump caught up. Even a tank with a lot of fuel in it can leave the pump dry as it sloshes from side to side on a winding road or even some grades. Its one of those situations where you may never notice there is a problem until something fails.....and then you may not know that fuel starvation caused early failure. Not saying that always happens, but how would someone know ?
I added a sump to my stock tank. I’m only running a 120 gph Carter mechanical pump and have never had issue with fuel starvation or fuel pressure.
It maybe, carburettor cars 6 ilb fuel pressure outlet in on the bottom,, Fi cars are pulling up to the top of tank at 30 psi, the pumps in the tank have to have some kind of baffle but more over a tray with a bleed hole for the sock filter to lay in, or they suck in air into the lines, which is no good, as it's all about venting at the motor end which is done by the carburettor, unlike the fuel injector which is simply an electric switch which fires out the fuel at 30 psi. The fuel line pressurised from the tank, i.e it's why you cannot run rubber fuel lines from the tank as they see pressure of 30psi .....pop!
My old, now kids car, has a baffled tank. It’s EFI, with the pump and pickup in from the top to the bottom. My understanding for the use of baffling sis to minimize a weight shift, not fuel starvation. My old trucks were tanks behind the seat and never thought/etc, I needed a baffle in her tank. But these tanks sat “skinny side” up, and I never tried to carve a canyon in them. But if you are building a tank, or buying one and there’s a option for a baffle, why not? Your wallet may be a bit lighter, but I can’t see it being cost prohibitive.
How much fuel does a high performance 5-6-7-800 horsepower V8 consume in a second? How much less fuel than normal can there be in the carb bowl before the engine runs leaner? I agree most street cars with carbs driven sensibly won't have noticeable problems, but on the other hand high performance engines under full power are sensitive to running lean and can blow up due to it.
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