old debate: 48 dells vs 48 IDA's

[nicolas]

i know there are the obvious visual differences, but has someone tested them both and come up with differences in performance, maybe one kind is better suited for one sort of engines and one for a different kind.

i am currently running 48 dells on my 2276 with an FK8 and CR is 8.7 (from memory), steve time stage 2 heads with 42x37 valves and i thnk they work great, but i haven't tested 48 IDA's so i can't compare. what would be the difference (advantages/disadvantages)

yes this topic is open for debate, but that is a good thing 

[65bug]

Nicolas,
      Those are great carbs bubba! I have 48 Dells on my motor and love them. IDA's do from what i understand have larger throttle bodies on them. They are bigger, even though both carbs are 48's. Unless you are just racing, the 48 dells should be more then ample! Very much so with those size heads you have! I have the same exact heads as you, but with a little larger ports, 5 angle valve job and blend ported manifolds. All the little things add up to more ponnies
        My motor is a 2165 with a Pauter cam. I run 9.7-1 on pump gas with no problems at all here in California.
Advantages: Maybe a bit more power with IDA's ??
Disadvantages: Transitions not as good. Not as smooth as Dells. More maintenance and adjusting more then likely with the Webers.
       But there are guys on here with alot more experience then me with carbs. DONT GET 48 CHINA CARBS. YOU WOULD BE VERY SORRY! Keep those Dells! Excellent carbs!
       

[LuftsickTero]

I am not racing anything and opt for driveability not the last HP from the given combination, the only problem with my 48 Dells was the Triple-D syndrome, Dreaded Dellorto Drip. Other than that I was perfectly happy with them, when they were in my 2161cc they were good enough for high 13-sec ETs but that's long time ago.

[rick m]

Contrary to what some may think....my IDAs are smooth as glass during the transition.  No stumbles, no popping, hesitation, etc.  I can drive them just like I could drive 48 dells.  In fact I have a set of 48 DELLS but I am using my IDAs on my next road trip just to see the variances in performance vs. a 48 Dell. They definitely make more motor noise with their thirsty throats!  LOL

Rick M

[65bug]

Rick,
     Would love to hear how they do on the long road trip! Did you have the modification done to your 48's to make them smoother at lower RPM's ? And what about power wise for Nicolas? Would he see a power difference with his size heads and cam? Hell, I am curious too! I really "Don't" know it all......................lol.
     
     LuftsickTero,
            I had a problem with one of mine where on of the plugs loosened or came out of it's passage. And it was probably my fault as the car was so out of tune it was backfiring! This caused fuel to run right out the float bowl down the throttle body into the manifold! I had to send it off to Art for a repair. Since then I have not had a single issue with them.

[Speed-Randy]

Rick,
     Would love to hear how they do on the long road trip! Did you have the modification done to your 48's to make them smoother at lower RPM's ? And what about power wise for Nicolas? Would he see a power difference with his size heads and cam? Hell, I am curious too! I really "Don't" know it all......................lol.
     
     LuftsickTero,
            I had a problem with one of mine where on of the plugs loosened or came out of it's passage. And it was probably my fault as the car was so out of tune it was backfiring! This caused fuel to run right out the float bowl down the throttle body into the manifold! I had to send it off to Art for a repair. Since then I have not had a single issue with them.

If you are refering to the 3rd progression hole, a properly jetted 48 Ida DOES NOT NEED IT!!! mine run great because they are jetted properly. I also have a set of the CHINESE 48's that I'm going to put on that car just to see how they run, because what I here is they actully produce a few MORE HP than the Italian IDA's.. We will see when I get around to it

[65bug]

Speed-Randy,
      Yes, I was referring to the third progression hole indeed. I have purchased a few Chinese parts in the past and was highly disappointed with the outcome. Total Junk! Maybe I am just not that lucky. I knew better with my crankshaft and other internal parts. Hope the carbs work well for you. Let us know.

[rick m]

I've had IDAs without the 3rd progression hole and with them and I can tell you that they do run smoother...regardless of the tune. Why do you think DELLORTO put 5 progression holes in their carbs?  The DELLORTO, in my opinion, is the smoothest running carb out there. I have owned everything from their 36's to the 48's and all of them ran smoother than any Weber I have ever run out of the box.  That being said,  I still like my IDAs and have a road trip that I will put about 2000 miles on them testing them at all elevations and heat ranges.  I have been driving them all over town the last 4-6 weeks refining the tune here in Arizona.

I just finished up putting a HAL meter and O2 sensor in my car.  The carbs are running right where I want them right now. I will keep track of their performance on this road trip. I have no reason to believe they will not perform flawlessly.  They are doing so now.  However, the $4 + dollar a gallon premium is not to my liking but we pay it if we want to enjoy using our cars.

RM

[Jesse/DVK]

You think $4 for a gallon is much? I pay $10 for a gallon..

One thing that I noticed during my dyno session that it is very important with IDA's to have a look at the idle jet holder size which make it much more driveable.

[Shane Noone]

One thing that I noticed during my dyno session that it is very important with IDA's to have a look at the idle jet holder size which make it much more driveable.
[/quote]

Hi Jesse, up until recently I have always ran with Dellorto DRLA's on the street and strip and really liked their smooth and totally trouble free performance. I had a set of 45's and then a set of 48's on two different motors. However on the motor with the 48's I was advised by the guy that built my motors, the power potential of the combination was being held back by the DRLA carb andI should really at that point go IDA. However I held off. Now with my new motor I have decided to give IDA's a go and been extremely frustrated by their performance on the road.( I know they are not really meant for road use but they say that about a lot of cam / head combo's and I always adapted my driving to cope ) However my IDA's are very hard to live with on the road. They were "set-up" by the guy that built and dyno'd the motor so the jetting should be right ( no reason for me to assume they are not ) In fact he played with the jetting and choke sizes a fair bit it seems on dyno sessions and adjusted the float settings etc a couple of times. But still the carbs seem incredibly rich at idle and low down RPM's -have a horrible flat spot between 2- 3500 rpm where you literally have to try and accelerate quickly through that band. If your in it at slow speed and try to pull away, the motor resists,carbs pop and spit and and the motor labours it's way until you pass 3500 and then it starts to clean up and past 4000rpm it's all fine. Trouble is on the road you would spend a lot of time between 2-3500 rpm's when cruising.


So I notice you commented on the change in idle jet holder to a 110 which made a great difference.

My idle jet holder is 120. Could this be a cause to my problems ?

Cheers, Shane.

[Jesse/DVK]

We dynoed two cars last Saturday. My friend has 2276 with IDA's 3 progression holes and 120 holders. I have 2176cc IDA's with 2 progression holes and we tried 110 idle jet holders. With my engine the hick up is lesser than my friends 2276. It drives smooth on the street and highway. When I drive a 2800 rpms for example and I just step on it offcourse it is running a bit 'heavy' but picks up quickly and certainly no carbs popping and spitting.

Just try and see if it works for you, combination of head and cam also have an effect on this.

Search for ALFA1750 on Ebay he sells idle jet holders in all sizes. Also search on here on idle jet holder a few topics discussed this.

[Shane Noone]

We dynoed two cars last Saturday. My friend has 2276 with IDA's 3 progression holes and 120 holders. I have 2176cc IDA's with 2 progression holes and we tried 110 idle jet holders. With my engine the hick up is lesser than my friends 2276. It drives smooth on the street and highway. When I drive a 2800 rpms for example and I just step on it offcourse it is running a bit 'heavy' but picks up quickly and certainly no carbs popping and spitting.

Just try and see if it works for you, combination of head and cam also have an effect on this.

Search for ALFA1750 on Ebay he sells idle jet holders in all sizes. Also search on here on idle jet holder a few topics discussed this.

Thanks Jesse. That info is interesting. So if your friends motor and yours are similar in spec, the smaller size idle jet holder must be an improvement for smooth driving as you don't have the 3rd progression hole, which I am sure I do have.  I certainly cannot step on it at 2800 rpm's That is completely in my "dead zone" .

Got to be worth a try as you say. Thanks.

[rick m]

Art Thraen, of ACE VW, is a master with IDAs.  He ran them on his 2 liter motor in his 66 bug.  Gary Berg also knows how to set up your carbs for street use.  Yes, the idle jet holders do matter.  My motor is a 2276 also.  K8 cam, 42x37.5 valves and 37mm vents.  I run 34 degrees advance in my motor.  It has "NO" flat spots anywhere.  I can stab it in any gear at almost any rpm and no flat spots. Compression is 8.7. I run a COMPUFIRE DIS ignition system. Plugs are gapped at .050.

Play with your idle jet holders and idle jets since your motor runs on them up to about 2600-3000 rpms.  I use my HAL METER to make sure things are where I want them in terms of the A/f/ ratio.  I run slightly rich to help control the temps in the motor.  I will post a shot of my HAL Meter and engine later.

RM

[Shane Noone]

Art Thraen, of ACE VW, is a master with IDAs.  He ran them on his 2 liter motor in his 66 bug.  Gary Berg also knows how to set up your carbs for street use.  Yes, the idle jet holders do matter.  My motor is a 2276 also.  K8 cam, 42x37.5 valves and 37mm vents.  I run 34 degrees advance in my motor.  It has "NO" flat spots anywhere.  I can stab it in any gear at almost any rpm and no flat spots. Compression is 8.7. I run a COMPUFIRE DIS ignition system. Plugs are gapped at .050.

Play with your idle jet holders and idle jets since your motor runs on them up to about 2600-3000 rpms.  I use my HAL METER to make sure things are where I want them in terms of the A/f/ ratio.  I run slightly rich to help control the temps in the motor.  I will post a shot of my HAL Meter and engine later.

RM

Hey Rick, thanks for that advice and info also. My motor is a little wilder component wise but it was always my intention and instruction to have a motor that I could drive reasonable smoothly on the street and be a terror at the strip. I know this is possible and have achieved it before with a similar spec 2276 on 48 DRLA's.


My motor now is 2332 with FK87 cam, 46 x 40 valves, and 44 vents, CR at 11:1, petronix billet dizzy with ignitor1 installed.

[65bug]

Rick,
    Would love to see a pic! I have a LM1 meter and once Mark Harney taught me how to use it over the phone and emails I got my Dell's dialed in pretty good. Slightly rich as well for street use! My 2165 runs soooo cool! I got schooled in proper engine tin work and hoover bits too! My 2165 at 9.7-1 CR runs so much more cooler then my last 1600 stock engine ever did! I can drive my car anywhere! On 87 octane 76 gasoline!
    I can totally relate to you on the engine tins! I purchased and had to modify some parts to get them to fit properly. Some of these posts I see on here I find hard to believe. But I am trying to be nice to everyone. You can even shoot spit wads at me and I will just smile............................lol
   

[Dano382]

Art Thraen, of ACE VW, is a master with IDAs.  He ran them on his 2 liter motor in his 66 bug.  Gary Berg also knows how to set up your carbs for street use.  Yes, the idle jet holders do matter.  My motor is a 2276 also.  K8 cam, 42x37.5 valves and 37mm vents.  I run 34 degrees advance in my motor.  It has "NO" flat spots anywhere.  I can stab it in any gear at almost any rpm and no flat spots. Compression is 8.7. I run a COMPUFIRE DIS ignition system. Plugs are gapped at .050.

Play with your idle jet holders and idle jets since your motor runs on them up to about 2600-3000 rpms.  I use my HAL METER to make sure things are where I want them in terms of the A/f/ ratio.  I run slightly rich to help control the temps in the motor.  I will post a shot of my HAL Meter and engine later.

RM

Hey Rick, thanks for that advice and info also. My motor is a little wilder component wise but it was always my intention and instruction to have a motor that I could drive reasonable smoothly on the street and be a terror at the strip. I know this is possible and have achieved it before with a similar spec 2276 on 48 DRLA's.


My motor now is 2332 with FK87 cam, 46 x 40 valves, and 44 vents, CR at 11:1, petronix billet dizzy with ignitor1 installed.

Shane, a smaller idle jet holder 100-110 will keep the idle circuit on longer and help with the transition to mains. Your main jet, and air jet have alot to do with that transition too, what jets and emulsion tubes are you running? Sounds like you are running lean, and that can cause it to run hotter as well.

[Shane Noone]

Dano,

To the best of my knowledge the emulsion tubes are F7 - the main is 180 and the air is 170.

It doesn't seem lean, quite the opposite.....

Interesting how the smaller idle holder helps smooth the transition - I am wondering if part of the trouble is slow air speed through the IDA's and into big intake ports and valves at low engine speeds....

[Dano382]

Dano,

To the best of my knowledge the emulsion tubes are F7 - the main is 180 and the air is 170.

It doesn't seem lean, quite the opposite.....

Interesting how the smaller idle holder helps smooth the transition - I am wondering if part of the trouble is slow air speed through the IDA's and into big intake ports and valves at low engine speeds....

Shane, could be with the 44mm chokes but you are running big valves. for the street it might like a 42mm choke. Not sure what your altitude is where you live but, I was running F7 too and went to a F2 with better results. I have seen the "squared" jetting your running but if you think its running rich then a 170 air jet is the wrong way and will cause the main to come in to early. Best way is to runit on a chassis dyno with a AFR meter to monitor whats going on. My 2332 is running f2 170m, 200a or 210a. 

[Cornpanzer]

I think that compression and port velocity play a big part in this as well. My 2276 w' FK8 and 10:1 was smooth as silk in transition. I had a tiny burble early on, but solved that by going up one size on idle jets.

[Shane Noone]

Hey Dano, someone else suggested F2's also so maybe that will help ? I will probably get the car down to a chassis dyno as you say to see what's going on low down the rpm range as I doubt much attention was paid to this on the stuska dyno as usually jetted correctly for maximum power at the high end range.

Cornpanzer. Yes, have been wondering about port velocity with big carbs / big ports and big valves....................also as you say CR versus cam profile with a street and strip motor.

Thanks.

[rick m]

I run F11s. They are smooth as glass off the idle circut during and through the transition into the 3000+ rpm range. (K8 Cam, 65idles, 165 Mains, 190 airs)

RM

[nicolas]

i start to assume that the FK8 is the hot ticket here!! 

as i run dells with that cam and everything is smooth too 

[rick m]

I picked up a friend at Sky Harbor tonight. Flew into town to complete the purchase of a 59 speedster for one of his clients. Picked him up from the airport in my Chop Top with IDAs.  He was stunned how smooth and drivable they were. No coughing, sputtering during the transition.  Can drive it like a stocker.  :-)  Will drive all weekend to the different VW activities we will be attending.

Rick M

[65bug]

SO I hear the weber copies come with the 5 progression holes! Is that true?

[Jesse/DVK]

Which copies? Empi?