Topic: PD carbs intake decision...

[wannabridin]

Hey guys.  I have a set of '77 PD carbs with accelerator pumps and adjustable needles awaiting cleaning and installation on my build, but i want some "definitive" answers on what intake i should run...

if i had it my way, i'd run velocity stacks, because of the looks.  but the lack of effective filtration worries me.  I had UNI pods on the bike before i started taking it down, and it ran great up in CO and down in TX.  a little bit boggy down low, but nothing a small handful of throttle and some clutch magic couldn't overcome!

so pods really look great with the cafe theme, but if they're a #$%* to tune, keep in sync and perform well overall, then i don't want them...  i have the airbox for the set of carbs and i can use that in the build, but those boxes are so big, heavy and ugly!!! 

can i get some advice on which to use, pods vs. stock airbox and why??  also, any tips or tricks as to make the airbox not look as ugly, or at least to hide it a little better??  thanks guys!

[TwoTired]

Do you have access to an engine/chassis dyno, that will give you a fuel map?
Or, a test track, spark plug deposit reading knowledge, and the time to do test runs/reading plugs/adjust, and repeat until, your track times are the best and the plug deposit are correct?

Do you know that you need to fiddle with the slide needle, main jet and pilot circuits?

[wannabridin]

i don't have access to a dyno or test track.  this project is about to be set in motion, so it will be an entire rebuild. 

i know how to fiddle with carbs, why did you ask about everything else?

[TwoTired]

i know how to fiddle with carbs, why did you ask about everything else?

Because carbs are adjusted to engine needs, given the existing breathing characteristics.  Changing those characteristics, even for cosmetic reasons, means determining what the new needs are. Then you adjust the carbs to provide what it requires.  Honda engineered all those bits to work together.  Your proposed "cosmetic" changes are actually engineering changes.
Test tracks or Dynos allow you to determine engine needs for the breathing conditions you've subjected the machine to.
Without "definitive" engine run data (from dyno, or plug reads), you just keep fiddling with the carbs until it's run characteristics stop annoying you. ...or you give up and sell it off.

[wannabridin]

oh i understand all this TT, but i was just wondering more or less with an overall opinion on pods vs. the stock airbox.  looks are important, but not as important as a properly tuned machine, so if looks have to be sacrificed somewhat in one area, then so be it! 

from what i know, the airbox will be easier to tune since it's engineered to work very well with the carbs, and you're not overcoming certain tuning hurdles that other forms of intakes can cause...  i've read that some people have had really good luck tuning pods to work, and i had pods on my bike before i put it up to start the rebuild and it ran great!  but i've also heard (a lot more of these people out there) that a lot of people would run pods, get pissed off at the tuning difficulties and then throw the airbox back on and BAM, great running bike with more power everywhere!  plus, i'm still on the edge about the sucking sound from pods...

[TwoTired]

...About the "data" point ;

i've read that some people have had really good luck tuning pods to work,...

Sometimes you have to qualify/disqualify this type of data, as there are different values of "work" and this is subjected to the interpretation of the those that report it.

How did they know it "worked".
Did they drive it around the block for the first time in 20 years after being "cafe'd" and declare victory?

Do they have any real numbers like an air fuel map, or track times showing an improvement over stock?  (at what RPMs and power settings?.

Just how accurate is their "Butt dyno"?

Was the POD change done in isolation from other changes?

What brand/style of "PODs" were they using (Does one size brand really fit all?.  If it's beer, it's all the same, right?)

How many of the POD proponents are just trying to convince themselves (and others) they did the right thing so they don't feel foolish about the choice they made?

There is only a couple of forum members that have any quantitative data on pod use, and those were on engines that a number of other mods made to the engine.
All the rest have been based on "I like the way it looks, so it must run better", camp.

IMO

[NickC]

If you like the look of pods, run pods. Tune it to where you are happy with it, and ride it.
Will it run perfect? probably not.
Will it perform as Honda had designed it? Probably not.
Will it implode when you put PODS on it? Probably not.

[wannabridin]

haha, nice way to put it!

TT, i thoroughly enjoy your posts as you overthink things just like me!  i'd rather have a well performing bike than a perfect looking bike, so i think the general consensus in my head is to keep the stock airbox and clean it up some to where it looks halfway acceptable 

i feel that i can tune this a lot more precisely because i'm working with what Honda had to make it better, rather than trying to reinvent the wheel my making one side flat and going from there...