Side drafts

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Scampin around

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How practical is a sidedraft set up for a daily driver? Same question for a duel carb set up? What would be the draw backs if any?
 
You're almost always going to be better off with a single appropriately-chosen, well-tuned carburetor than with two or more carbs, unless the primary main objective is to make people go "Whoah, cool" when you open the hood. Everything is more of a hassle with multiple carbs. Carburetor matching, tuning, and synchronisation, throttle linkage, choke linkage, kickdown linkage, air cleaners, etc.
 
How practical is a sidedraft set up for a daily driver? Same question for a duel carb set up? What would be the draw backs if any?
Depends on conditions, how brisk does it get out there in SF? Also depends on what You consider to be acceptable to qualify as practical. Any set-up once properly tuned &
installed, is just as practical as any other, other than warm-up times/cold driveability and associated fuel waste/contamination of the oil. Even a stock intake & carb is less
practical by far once headers etc. are installed, for year 'round driving, not to mention would need re-calibrated without any exhaust heat present.
 
No.. a side draft setup completely defies what a slant SIx best qualities are . Low end torque, reliability, and concrete usefulness You got 20-30 k to blow away ,have at it.
 
The biggest expense after buying the manifold and the carbs is the different jets, emulsion tubes, chokes, etc needed to tune your carbs for your engine. I have about $1300 in my setup: 3 matching Italian-made DCOE45’s and Australian slant manifold which included everything needed to hook up each carb to the main cross rod that’s mounted from one end of the manifold to the other end. This setup as bought will allow the engine to run.
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To optimize the carbs for the engine will no doubt require different idle and main jets, chokes, emulsion tubes etc and since you will need three each time when tuning, that can get expensive in a hurry. As Dan said much easier to run a single carb and cheaper as well. And again true when you open the hood - there’s the Wow factor.
 
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It costs just about as much for a triple weber setup as converting to EFI.
LOL, what kind of EFI ? With an inline pump maybe, and You'd better keep over 1/2 tank of fuel in it at all times unless You're driving like a 95 yr. old granny (Fitech system being the only exception).Any TBI
system is going to have the same fuel distribution issues any single carb set-up would have. Performance & cool factor wise forget it..............No way I'm buyin You can
do a proper MPFI EFI job anywhere near as cheap, and You've got one hell of a lot more work ahead of You than some hoses & linkages.
 
So you think it is easier to sync and tune triple webers, then punch numbers into a computer screen. Maybe it is, I didn't have much trouble with a weber on my old British sports car, certainly better then the dual SUs.

A triple weber setup is between $1200 and $1500 when done.

I will have around $1000 in the MP-EFI setup that I am installing. And yeah, I am using an inline fuel pump. It will sit under the surge tank that is being feed with a BBM fuel pump along with a complete return style system. When done, I will have complete control of fuel and ignition. Something that weber setup won't have.
 
I had a triple Weber setup on on old 240Z and like someone said they like rpms. I could stab my Z below 3000 and it would cough and spit then go but above 3 look out. Lol.
 
How practical is a sidedraft set up for a daily driver? Same question for a duel carb set up? What would be the draw backs if any?
How much time do you have to tune?I ask because I had side draft webers on my sprint car (street legal) and I had to constantly tune the engine. Not quite a daily driver but close, I drive it around town (Livermore) a lot. I finally solved the problem by going to EFI and keeping the carbs as throttle bodies.

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Quite a few vids of some nice smooth running fitech powered inlines on you tube.

If it runs as nice as the 67 pony i saw on there with the fitech go street tbi im gladly in over a 3 carb setup, **** for a daily driver if i spend the money and it runs cleaner, gains me mpg and gets a bit more hp, im 100% for tbi.
 
So you think it is easier to sync and tune triple webers, then punch numbers into a computer screen. I DIDN'T SAY ANY SUCH THING, BUT IT MIGHT DEPENDING ON WHAT COMES MORE NATURALLY TO THE TUNER. Maybe it is, I didn't have much trouble with a weber on my old British sports car, certainly better then the dual SUs.

A triple weber setup is between $1200 and $1500 when done.
DEPENDS ON LOTS OF THINGS, BUT TAKEN AS KNOWN GOOD UNITS IN CURRENT RUNNING ORDER, SURE...SOUNDS REASONABLE.
I will have around $1000 in the MP-EFI setup that I am installing. And yeah, I am using an inline fuel pump. It will sit under the surge tank that is being feed with a BBM fuel pump along with a complete return style system. When done, I will have complete control of fuel and ignition. Something that weber setup won't have.
RIGHT, HOW LONG 'YA BEEN WORKIN' ON THAT?
 
How much time do you have to tune?I ask because I had side draft webers on my sprint car (street legal) and I had to constantly tune the engine. Not quite a daily driver but close, I drive it around town (Livermore) a lot. I finally solved the problem by going to EFI and keeping the carbs as throttle bodies.
And I hear that a lot, they constantly need fussing over, WHY? "I had to constantly tune the engine" is ridiculous, if that is the case these carbs aren't worth a S#*T, other
than linkage deficiencies needing re-sync'd too often what "goes out"?
 
I'm always a proponent of efi, but I've long thought that using cv carbs from motorcycles wouldn't be too bad with a stick shift. You could use three pairs of ninja 500 carbs, or pilfer two sets of four from a great many bikes.

Or even 6-bank carbs from a cbx or Kawasaki 1300.

That said, side draft EFI would be possible with bike throttle bodies as well.
 
And I hear that a lot, they constantly need fussing over, WHY? "I had to constantly tune the engine" is ridiculous

…and yet, we hear it a lot. From people who've been there and done that. Some of them just bit off more than they could chew and didn't know what they were getting into. Some of them tried to cheap out and use bad (worn out or Chinese) carburetors. Some of them had unrealistic expectations. But even if we ignore all those…we still hear, from people who know what the duck they're doing and saying, about the constant fiddlefutzing multiple carbs require, especially sidedrafts.

Multi-sidedraft-carb setups can work well, but it does require a great deal of fussing and fiddling and tuning and tweaking to get there, and a lesser but still notable amount to stay there.

other than linkage deficiencies needing re-sync'd too often what "goes out"?

Well, first you have to get "in" (all the way correctly dialled in, jetted, calibrated, adjusted) and that takes a lot more work than most people realise, and it can drag out long. You get the car running well, then it gets 10 degrees warmer out and you find a new batch of problems to fix, so you fix those, but then it gets another 15 degrees warmer out and you've got new driveability issues and you're still having fuel-consumption issues, so you work those out, but now the damn thing is a bіtch to get started and keep running until it's warmed up, then the weather changes again, etc. I think a lot of the constant tuning need we hear about isn't trying to keep it tuned, it's trying to get it tuned. (And then yeah, there are linkage issues, too.)

Then you've gotta figure that most of the kinds of carbs you might conceivably use in a multi-sidedraft setup—SUs, Webers, Dell'ortos, Zeniths—are entire fields of study all their own, with a whole lot of stuff to know and a few "rock star" specialists who can make 'em walk and talk and devoted fans who can keep 'em working well, and then a whole bunch of people who know just enough to get in trouble and as a result think the carbs are junk.

All that said, there are multi-sidedraft setups that run well. Factory ones (Volvo twin SU or Zenith, Datsun Z-cars with Hitachi carbs, etc) that reliably work great—have cubic mountains of factory R&D effort and expense behind them. There have been some thoughtful, skilled aftermarket multi-sidedraft setups that run well—but they need a lot of planning, work, and dialling-in, and are never the result of just grabbin' parts and tossin' 'em on.

As for motorcycle carbs: Yep, been done. See Fopar's '63 Dart here and here.
 
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RIGHT, HOW LONG 'YA BEEN WORKIN' ON THAT?
When I started collecting the parts, the megasquirt was at version one. So... money dosen't grow on trees around here.

Also during that period, i have designed and built 3 intakes to suport a GM M90. Since the m90 uses a serpentine belt, i had to design a serpentine belt system. Since ready available headers won't fit around the manifold I built my own.

What have you been doing?
 
I can tell you as a motorcyclist, the headache of a 4 cylinder carbed motorcycle is irritating. Add syncing carbs with a rack of 4 vacuum guages to your list of maintenance.

Jetting was always a constant once sorted, but on a slant six, 6 carbs, with six mains, 6 floats, 6 pilot jets and 6 pilot screws to tune, then make sure they dont crud up.....6 vacuum guages

I wouldnt go back from my newer efi bikes...
 
I can tell you as a motorcyclist, the headache of a 4 cylinder carbed motorcycle is irritating. Add syncing carbs with a rack of 4 vacuum guages to your list of maintenance.

Jetting was always a constant once sorted, but on a slant six, 6 carbs, with six mains, 6 floats, 6 pilot jets and 6 pilot screws to tune, then make sure they dont crud up.....6 vacuum guages

I wouldnt go back from my newer efi bikes...
I can tell you as a motorcyclist, the headache of a 4 cylinder carbed motorcycle is irritating.

As an owner of a Suzuki GS550 in my younger days, I drove it everywhere while stationed on Guam and shipped it back to Virginia when I got transferred. I commuted from where I lived in VA to Andrews AFB for 4 years Spring, Summer and Fall and got it out sometimes during the winter if it wasn’t too hateful out. Never once touched the carbs on that bike.
 
My kz650 never really liked to stay in sync super long

Should note, my cv carbed bikes were pretty good, the vm34 i had on my xs650 were dual throttle cable, and synced that way. Awful, i cant imagine 6. Linkage is a ton more stable
 
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A pair of HS6 SU's on a mild slant would be a wonderful setup. A pair of bog-proof carbs with no accelerator pump, what's not to like.
 
When I started collecting the parts, the megasquirt was at version one. So... money dosen't grow on trees around here.

Also during that period, i have designed and built 3 intakes to suport a GM M90. Since the m90 uses a serpentine belt, i had to design a serpentine belt system. Since ready available headers won't fit around the manifold I built my own.

What have you been doing?
Artfully dodging the question, how long has the project taken? It's admirable that You are motivated & capable, I designed a slanty intake years ago for a 4bbl, to find it
by accident 8 yrs. later masquerading as a short runner AussiSpeed Hurricane. Lol. My plan was sheetmetal 6061-T6 tho', made the patterns, have the sheet of
al-u-minimum. I have been kicking ideas around to make it an "active" intake, so I haven't committed to cutting it all out yet & borrowing My friends TIG, wheels still
turning..........
The problem here is, practicality is determined by a number of things, reliability being one of the most important facets. Driveability being the other top priority, it depends
largely on local climate/conditions, and functional aids such as chokes, intake heat or lack thereof, heated air to prevent icing etc. The last large determining factor is the
owner's tolerance for less than perfect behavior under all conditions, high,low,somewhere in between?
I'll be frank, I know SanFran can be brisk, I DO know that I left Vegas in July at 7:00AM & 85deg, and landed in SanJose in the low 50's...DAMN!! So I don't know what
temp swings occur out there, but sidedrafts are no different than any other setup with an unheated intake and needing rejetted to be "perfect" with temp & baro changes.
Fuel injection is wonderful, and I'm not recommending against it by any stretch, but if You're trying to tell Me it's easier to home engineer,set-up and get functional an
EFI system than bolt on the mannys & set up fuel supply and linkages.....BEFORE one starts tuning..............I gotta disagree with Ya on that one.

As far as what have I been doing, You don't wanna hear about all of it,.....& most of it's not for Me! I have gotten some of My toys to progress along, but right now I need
to get back to My Friends 452 heads, 1st crack at doing 2.18's w/the 1.81's.......before I'm not so good a Friend...LOL!!
 
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