Triple Dellortos ready to install

[modular9]

sulio : Dont want to thread jack so quick story Taken the dellortos off and put the SU's back on. engine is wheezing ( I actually saw oil leaking into the combustion chamber!! ) and cant use the power from the dellortos .

 

Very pleased that you got everything sorted. Take some youtube video so we can hear it !

[Toecutter]

Mike,

 

I ran my carbs on a fresh set of plugs and they worked fine but fouled after a few short start and stops. I then installed the return line as I found the mechanical pump was pressurising the the carbs. The fella at a local Alpha garage that sets up Dellortos quite a bit advised the return line orifice/restrictor should be at least 3mm the stock rail has approx 1mm hole so I drilled it out to 3mm, (he advised that when they are set up on Alphas they have a return line with no orifice plate and still fine, and thats with 500cc per carb throat). I've installed the old rail as for now as I did'nt have a through type banjo on the last carb. Anyhow the result is the same you get fuel return working with no pressure build up and running approx 2 to 2.5 psi. Dimitri (Zedman240) very kindly gave me a hand and Mick74 of coarse always ready to share his well of Dellorto knowledge has got me to a point where my carbs are running very nicely. I ran the car pretty hard for a couple of ten minute sessions and found all plugs to be burning nicely when inspected. I will however install the 55 idle jets as I think 60 are too big. I have also bought 5 off 7772.6 emmulsion tubes and looking for the last one if anybody has one to sell please advise.

 

Cheers,

Sulio

[Toecutter]

Well since last update I have installed the 7772.6 emmulsion tubes (previously 7772.10) and also 55 idle jets (previously 60's). The car is more responsive and more power from idle to 5000rpm. new emulsion tubes it's running richer mixture, Current power peaks at 5000rpm. I believe the 130 main jets are too small and need to go bigger. Perhaps 140's. See how she goes once they are installed but might even look at bigger air correcotrs.

 

 

An updated settings progress chart below:

 

2745_.pdf

[modular9]

Thanks for the updates. amazon delivered my how to powertune webers and dellortos and it has me thinking about those progression holes on the emission carbs. Say you were to block 2 of them up and get the progression holes down to the level of the non emission carbs ? and we got the restrictors in place then surely we would be closer to the non emission carbs ?

 

One last question : is yours a daily driver ? and if so do you have to sit in rush hour traffic ? the reason i ask is that my car chuffed while i was in traffic and i was talking to some guys about the triples and they reckon for the type of driving i do i should ditch em for efi +turbo.

[Toecutter]

Thanks for the updates. amazon delivered my how to powertune webers and dellortos and it has me thinking about those progression holes on the emission carbs. Say you were to block 2 of them up and get the progression holes down to the level of the non emission carbs ? and we got the restrictors in place then surely we would be closer to the non emission carbs ?

 

?

 

nah not my daily car. I'm pretty happy with how it drives though, will be keen to see it on a dyno once i'm done.

 

Sulio

[modular9]

Thats ok i was just brain farting on how to turn an emissions ( hard to tune + bad AFM problems ) to non emissions carb versions

 

Ahh so you dont need to sit in traffic for 1 hour in the morning and 1.5 hours at night. I need to find someone who is daily driving + rush hour traffic with triples. I think they just might be the wrong carbs.

[Toecutter]

Thats ok i was just brain farting on how to turn an emissions ( hard to tune + bad AFM problems ) to non emissions carb versions

 

hmmm...Mike, I think you have had some bad luck as I've found them pretty easy to tune seeing I've had no previous carb tuning experience other than tinkering with my SU's. The tripples actually start better than the SU's in the morning, just two pumps and she fires.

 

Ahh so you dont need to sit in traffic for 1 hour in the morning and 1.5 hours at night. I need to find someone who is daily driving + rush hour traffic with triples. I think they just might be the wrong carbs.

 

na, your right but my house is on the outskirts of the CBD and I've driven through the city from my office (where I keep my Z) to the house in stop start traffic and I had no issues. My only concern would be goign through fuel as a daily driver. I have'nt measured the diff between the SU's and tripples but I'm sure there would be a bit less economy there.

I agree with you that you will have less head aches with EFI and turbo. Expensive but if it's a daily driver I would see it as a good investment as it will behave nicely once set up running of an ECU.

 

 

[modular9]

Not so much as bad luck as over hyping the triples in my mind. I was really disappointed with the performance ( i come from v8 torana's,falcons and monaro's so you gotta keep that in mind when i say disappointed).

 

I think if i had my time again i would definitly counsel against triples for performance purposes. Especially after you see what can be done with EFI +turbo. When you say expensive it actually will work out ... wait for it ... at 2/3rds the price i have spent on the dellorto's so far. That is factoring in the decompression needed for the engine and standalone ECU plus turbo and routing hoses and so forth! If only there was a CTRL+Z for real life. But i digress...

 

I dont think you have taken the obligatory "rev the tits out of my engine induction sound" youtube yet. What gives ?

[Toecutter]

I dont think you have taken the obligatory "rev the tits out of my engine induction sound" youtube yet. What gives ?

 

Yer induction sound is ok but I expected a more re induction sound to be honest. Yes I do have to get some video of it, the problem is the car is currently stored down stairs in our work shop at work which is convinient but I generally do what I need to do and clear out of there as it starts to feel like I'm at the office night and day. Will get some vid when I get back from work trip next Monday.

 

Sulio

[ZD44TT]

anyhow updated sheet attached below...

 

that info is gold bud.........hope I never have to use it, for my liquidity sakes.

 

LOL.

 

 

[Toecutter]

that info is gold bud.........hope I never have to use it, for my liquidity sakes.

 

LOL.

 

are thinking about going down the tripple path?

 

Sulio

[Toecutter]

Michael,

 

Data sheet for the LSM-11 we were discussing, (just in case others are inetersted it is to be coupled to AFR gauge to give real time AFR readings and help tuning carbs, pretty accurate way to know how they are running under load and fine tune adjsutmets if necassary).

 

SUlio

2762_.pdf

[Toecutter]

Just out of curiosity I thought I'd install the spare 155 main jets i had. Obviously made mixture very rich and power dropped right off on both mid range and top end. Stopped pulling after 4000rpm with the 155's.

 

Sulio

2794_.pdf

[luvemfast]

Great info Sulio.

Maybe it should be a sticky?

[Toecutter]

Great info Sulio.

Maybe it should be a sticky?

 

Done Simon! I need to update the sheet with Warrenz config but I'll wait til he has his fianl set up as he's still tinkering although very close.

 

Sulio

[Toecutter]

Well my final set up. Sulio Final Settings, 06/10/2008

L28

DHLA40L

chokes 32mm

7848.3

main jets 130

air correctors 195

emmulsion tubes 7772.6

idels 49

air bleeds reduced to 0.9mm from 2.0mm*

pump jets 38

 

Stock L28, N42/N42, elec dizzy, headers

NOTES:

46 idle was too lean at 2500rpm. Gradually leaned out so was'nt far out. 49's provide a great progression. No hesitation any where does'nt matter how it's driven or what rev range with what should be the best possible economy as any lower on jetting mains or idle runs it too lean.

 

No further tinkering required.

 

Sulio

4306_.pdf

[warrenz]

For the record my final set up is:-

 

L24

DHLA40G

Chokes 32mm

Venturi 7848.3

main jets 125

air correctors 190

emmulsion tubes 7772.8

idle jets 46

air bleeds reduced to 0.9mm from 2.0mm*

Acc pump jets 35

 

Stock L24, Standard distributor with Pertronix Electronic ignition, headers, 2.25" exhaust.

One carby is modified to connect vacuum advance.

 

Pretty happy with that.

 

Warren

 

[Glen]

Hi, i just put my dellortos on yesterday and today took them for a bit of a spin. So far some hesitation when you first put the pedal down. Running 2psi in fuel with a restricted return line.

I get a lot of popping but it gets better the more i open the fuel mixture. I have read to start with 2 1/2 turns out but im more like 4 turns out. heres a list of what i am running. I sometimes have to nurse it through the revs at the bottom end. If i was to cruise in 5th the motor would more likely die then rev out. it feels like its drowning a little down low.

 

All carbys have been balanced and a new set of plugs have been fitted.

 

L26 stock

extractors and elect dizzy:-

 

L26

DHLA40

Chokes 30mm

Idle holder/emmulsion tube 7850.1

main jets 132

air correctors 180

emmulsion tubes 7772.5

idle jets 45

air bleeds dont need to be restricted on my carbys

Acc pump jets 40

 

Is there anything that stands out to anyone?, which jet should i be looking at to improve my hesitation. Im not after super performance, just trying to get the best out of em with out spending big as these carbs are really for my next motor and most of the jets/chokes will get changed out of these.

 

BTW i love the induction sound

 

[Scoota G]

Is the popping through the exhaust or the carbies?

[Toecutter]

From my limited observations if it's popping at the carbs then your running lean if at the exhaust then rich as it's unburnt fuel. It's very hard to guess from just that but looking at the jets your running I'd try 125 mains and see if you get an improvement as you also have 7772.5 emmulsions which are pretty rich re fuel. I think of it as sort of a ratio, ie there a stoich point that will work best re O2 mixture, you can acheive the same result by using richer emmulsion tubes and smaller mains or vise versa.

 

Also does the hesistation happen at wide open throttle or when you just gear down and smoothly try and take off. Remember when you pump the accelerator/pump jets kick it with a squirt. You have a transitional rev range where you move from feeding off idle jets to main jets. I beleive that roughly about 2000revs and people often get falt spots there because the idles might be too small. You can also fine tune your idle mixture with the air corrector on the idles. As you have the performance carbs there more room for you to piss fart around unlike you mates carb that require the reducer ie air bleed.

 

Just keep in mind that those idle jets are not reallr for idle as much as that they are for the sub 2000rev drving including the transition.

 

Another thing that can get you those flat spots is if the carbs are not in sync re air flow and also opening at the same time.

 

I'm no expert on these carbs, just stuff people on this forum have told me and my own tinkering so the points above are just based on trial and error.

 

I have a spare set of 125 mains you can try out with a few sets of idles and 7222.10 emmuslion tubes. I think Sachi has got them atm. He might chime in on when he might be finished with them.

 

Sulio   

[ol_skl_jp]

Sulio, i have got your 46 idle jets. Unfortunately the setup Warren and i tested (and worked so beautifully when testing) wasn't so hot on the way home.

 

Probably spend the whole day tomorrow tuning:

DHLA40

Chokes 32mm

Idle holder/emmulsion tube 7850.1

main jets 130

air correctors 200

emmulsion tubes 7772.5

idle jets 46

Acc pump jets 33

 

Sach

[Scoota G]

I'm thinking under load, up the pump jets, i think they are too small.

[Glen]

From my limited observations if it's popping at the carbs then your running lean if at the exhaust then rich as it's unburnt fuel. It's very hard to guess from just that but looking at the jets your running I'd try 125 mains and see if you get an improvement as you also have 7772.5 emmulsions which are pretty rich re fuel. I think of it as sort of a ratio, ie there a stoich point that will work best re O2 mixture, you can acheive the same result by using richer emmulsion tubes and smaller mains or vise versa.

 

Also does the hesistation happen at wide open throttle or when you just gear down and smoothly try and take off. Remember when you pump the accelerator/pump jets kick it with a squirt. You have a transitional rev range where you move from feeding off idle jets to main jets. I beleive that roughly about 2000revs and people often get falt spots there because the idles might be too small. You can also fine tune your idle mixture with the air corrector on the idles. As you have the performance carbs there more room for you to piss fart around unlike you mates carb that require the reducer ie air bleed.

 

Just keep in mind that those idle jets are not reallr for idle as much as that they are for the sub 2000rev drving including the transition.

 

Another thing that can get you those flat spots is if the carbs are not in sync re air flow and also opening at the same time.

 

I'm no expert on these carbs, just stuff people on this forum have told me and my own tinkering so the points above are just based on trial and error.

 

I have a spare set of 125 mains you can try out with a few sets of idles and 7222.10 emmuslion tubes. I think Sachi has got them atm. He might chime in on when he might be finished with them.

 

Sulio   

 

I shall have another look and drive tomorrow, hesitation is there full time but, i have to see if it hesitates after cruising on 3500rpm or under 2000rpm. I can see where your going i think

I get popping through the exhaust on decompression and a little on acceleration. Should i just keep letting the mixture out til the popping stops through the carbs or is that making things worse. I fear more pooping in the exhaust on decompression. But it sounds good and im going for some decent flame out of the exhaust  jks.

 

More trial and error tomorrow Ended up getting to warm today thrashing the poor 2.6 At one stage my eyeballs were stuck to the windscreen thinking my carby's were on fire and panicked even further when one realsied there was no extinguisher in the car. Its always my fear when fitting carbys.

 

Thanks scoota will have a look for some jets.

 

Cheers lads

[Scoota G]

This is a good time to catch me because i have a shite load of carbs at the moment with a lot of tuning variables. I will list what i have in "The Dellorto Pool" tomorrow.

[warrenz]

Sulio - I have the rest of your jets etc, Sach only has the 46 idles. I can drop them round Monday night if needed as I'm off to SA over xmas.

 

From the experiences I went through I can only stress what Sulio said, all carby's need to be in sync, ie linkages operating all butterflies at the same time, all butterflies coming back to the same point every time, all pump jets starting to squirt fuel into the venturis at the same time.

 

Check the pump jets in case it is blocked on one choke and not squirting fuel (use a mirror)

 

Also if you are using soft mounts make sure there are no air leaks (that was one of the problems I had). If there is no noticeable change in the idle when you wind the idle screws in and out then their is a fair chance air is getting sucked in somewhere else. I think Sach has got that issue.

 

I know how frustrating this can be, but perseverance and methodically eliminating possibilities is the way to go.

 

Warren