Why convert EFI to Carbs!?

[LJ851]

they make carbs with multiple barrels.

No.

[BlackbirdM3]

It would lose substantial power on one end of powerband, take your pick.

The Alfa example you mention is true, but ITB's would beat the webers in power and drivability hands down, every day.

The main reason your (or my) carbed cars start quicker is because there is nothing telling the car not to start until it "sees" a certain # of the required signals like most OEM injection systems do.


There are some carb setups can produce similar power levels across the RPM band compared to injection but it (unfortunately) will never be a sidedraft weber carb.

I sincerely wish this wasn't true because i love them and am using them on my M30.

Personally I'm a Mikuni guy, I've never gotten a set of Webers to run right 2 days in a row. I'll happily give up something below 1500 rpm to make gains up top any day of the week. My Datsun is a little sluggish below 1500 rpm ,but its not there long enough to make a difference. Oh yeah, I can light the back end up with race tires off idle any time I want. On the S14, I'd be interested in doing it just to be different. Set it up with a nice big open ITG airfilter over the correct sized velocity stacks and listen to the sound. Screw the carbon air box, I want the full sound with very little/nothing muffling it ;)

Sure, a set of TWM Induction ITBs would sound the same as a set of Weber/Mikunis, but you need a PhD in computer programming to deal with them so its totally not worth it to me. I also hate paying someone else to fix/tune a car. If I cant fix it or tune it myself, I shouldn't have bought it or screwed with it in the first place. The exception being when I flat out don't have and can't afford the tools to do it myself. Since I don't have a clue about computer programming, trying to tune EFI scares the crap out of me. Do I want bigger cams, the Miller Motorsports AFM to MAF conversion, and the WAR chip for my M3? You bet. Do I have a clue how to tune it? Nope. Hence the reason I haven't made the upgrade. I also don't have access to a chassis dyno. I like simple stupid, and I really dislike electrical gremlins. Modern engines are neither simple, and they are all electrical gremlins waiting to happen. To be honest, if something old school comes along that I really like, I'll trade the M3 for it in a heartbeat. A clean rust free E9 3.0Cs could be sweet, but it would have to be the right one. A '71 Skyline KGP10GT could be a no brainer as well. Either way, they will have a set of carbs on them that I can tune.

Will

[Beske]

Why? Why not!



Best thing I got for my car since I have it!

[SkiFree]

Why? Why not!

exactly!

For me it's the fun of working on something analogue vs. a computer. The sound doesn't hurt either!
Reference for M20 Triple Weber sound..... http://www.youtube.com/watch?v=UuatOtGmV_w

Explain how you can make a better race car with carburetors over Electronic Fuel injection.

You can't, if that's why your considering carbs, then you're barking up the wrong tree.

[BlackbirdM3]

exactly!

For me it's the fun of working on something analogue vs. a computer. The sound doesn't hurt either!
Reference for M20 Triple Weber sound..... http://www.youtube.com/watch?v=UuatOtGmV_w




You can't, if that's why your considering carbs, then you're barking up the wrong tree.

Sweet, I'm not the only person here with this mind set. As far as racing, I vintage race so EFI is illegal anyway. :) Heck, before I went overboard and made the race car 95% race car, 5% street car, it used to get about 30 mpg turning 5K rpm on the freeway. Oh yeah, same carbs, but less cam, and less venturi, I only had the stock 37s in them at the time as well as the stock cam.

Here (I hope) is a dyno sheet from before I went really overboard.

http://www.cardomain.com/ride/737676/1969-datsun-roadster/page-4#7376760011

Its got more power now. The power curve is about the same, there is just more of it. Carbs work fine for me. :)

Will

[Beske]

Hell yeah they sound awesome!

My 316 m10 with twin Dellorto DHLA 40's:

http://www.youtube.com/watch?v=fmYvsQatP_k&feature=player_embedded

My engine is dying and the carburettors aren't properly tuned (first test drive in the video) so the performance can be better but the sound is already amazing.

[LJ851]

Personally I'm a Mikuni guy, I've never gotten a set of Webers to run right 2 days in a row. I'll happily give up something below 1500 rpm to make gains up top any day of the week. My Datsun is a little sluggish below 1500 rpm ,but its not there long enough to make a difference. Oh yeah, I can light the back end up with race tires off idle any time I want. On the S14, I'd be interested in doing it just to be different. Set it up with a nice big open ITG airfilter over the correct sized velocity stacks and listen to the sound. Screw the carbon air box, I want the full sound with very little/nothing muffling it ;)

Sure, a set of TWM Induction ITBs would sound the same as a set of Weber/Mikunis, but you need a PhD in computer programming to deal with them so its totally not worth it to me. I also hate paying someone else to fix/tune a car. If I cant fix it or tune it myself, I shouldn't have bought it or screwed with it in the first place. The exception being when I flat out don't have and can't afford the tools to do it myself. Since I don't have a clue about computer programming, trying to tune EFI scares the crap out of me. Do I want bigger cams, the Miller Motorsports AFM to MAF conversion, and the WAR chip for my M3? You bet. Do I have a clue how to tune it? Nope. Hence the reason I haven't made the upgrade. I also don't have access to a chassis dyno. I like simple stupid, and I really dislike electrical gremlins. Modern engines are neither simple, and they are all electrical gremlins waiting to happen. To be honest, if something old school comes along that I really like, I'll trade the M3 for it in a heartbeat. A clean rust free E9 3.0Cs could be sweet, but it would have to be the right one. A '71 Skyline KGP10GT could be a no brainer as well. Either way, they will have a set of carbs on them that I can tune.

Will

I agree with all of this except the fear of EFI and EFI tuning although i used to feel exactly the same way. Spending the last 15 years or so wrenching on motorcycles for a living and spending many,many hours dyno tuning carbed and injected machines cured me of that. Standalone EFI really is not difficult to tune once you get your head around it (and have a wide band of course). I am not computer savvy at all and i can do it!

My E30 is the newest car i have ever owned and it's electrical complexity bothers me as well, even though it is supremely simple compared to todays offerings. My 3 other vehicles are all from the 1960's and they are way more my style.

There was/is a guy around here running an E9 with a sidedraft equipped S38 engine in it that was fairly awesome. I might have a picture of the engine somewhere...

[AndrewBird]

Carbs will generally have much better throttle response then a single throttle body style EFI setup. But if you go individual throttle bodies, it becomes null.

[BMC227]

Because people are stupid, that's why.

You're being stupid, i bet you haven't got a clue about cars/motors.


To the OP,

Carbs are good only if you've got a wide range of jetting on hand and if you know what you're doing.

Here are some pics of my heavily modified M30 triple carb engine

[xwill112x]

Carbs will make more peak power at WOT than a FI setup, And you can get away with way more than 850 cfm in a "850 cfm" carb. They're all generic so to speak. You're not winning if you're not cheating on the racetrack. Oh and their easy to jet up or down for weather conditions to correct the horsepower vs a FI setup. Get your self a flow bench and dyno and you will see.

They both have pros and cons, the FI setup will be more street friendly and have less maintenance for a daily driver or street car. And before anyone calls BS, I have credits in courses of specific training, have talking to the old goats who know their shit in nascar, as well as had many hours on the flow benches with heads with carbs, etc.

[Roysneon]

12v charging system is also bullshit, I'm currently shopping for some simple points for my new flathead I8 swap.

[e30s50dan]

because RAUH WELT BEGRIFF

Been there....done that!

[EThirty318i]

Because an M20 with triple webers is a glorious thing.

^ This

[e30s50dan]

Oh and I got like 10-12mpg on a 2.5l ...but what glorious sound

[Fusion]

Because Nascar.