Triple Webers: the low-down

[moyest]

I wish I had a photo, but it's too soon - I only got my car back from the mechanic last night... Brand new TRIPLE WEBERS on a TWM manifold, fitted and tuned~

Here's some info. for the punters out there considering a triple carb set-up (especially Webers), because I never found a "comprehensive" thread on the website that gives enough info about the topic. So here goes:

RESEARCH: The cost of Weber carbs varies greatly between different suppliers, wholesale and retail. I don't want to give any wholesalers or retailers a free "plug" here, especially because I didn't purchase through any. But I did do the research before I bought mine privately, and the price varies about US$200-$350 just for the carbs and manifold (and that's comparing the same brand manifold, because you can't compare a TWM manifold to a Cannon manifold, for example).

DCOE45's: I've seen a few threads about which size carb to use in the triple set-up. The conclusion in most of those threads seems to be to go for DCOE40's. That's probably correct if you are running a stock standard engine (L24 block), but I'm not. My L24 has a ported/polished head and a re-profiled cam (although still fairly "mild" and streetable), also with a sports exhaust. On my set-up the DCOE45's worked a treat!

CARB SPECS: When you buy your carbs, try to get a set that have been set up correctly for your engine. When sellers tell you that you'll only need to "re-jet" them, they're lying!!! There's jets, chokes, venturies, emulsion tubes... The jets are probably the cheaper items to replace and play with, but venturies and emulsion tubes can be very expensive to have to replace! Just remember, you need SIX OF EVERYTHING on the twin-choke triple carb set-ups. LUCKILY, I bought my carbs off a friendly chap in sunny Florida who had bought the right set-up. So close in fact that I only had to get different jets to have it running properly.

DYNO-TUNING: This is a must. You've got to get it right the first time, otherwise you'll have some expensive engine hardware that doesn't add to performance at all. The extra fee for time spent on the Dyno is minimal, compared to the cost of having to have them constantly re-tuned if you get it wrong.

:mad: MECHANICS: Obviously they have to have a Dyno! But it also helps if they've set up a Z before. Again, by sheer LUCK I used mechanics who knew their way around Z cars. The workshop owner's son drives a modified 240Z (turbo), and the owner drives an even MORE modified 240Z (RB26 engine from Skyline GTR). BUT, they were expensive. I must admit I felt "ripped off" when I got the bill for $1,300 (that's Australian dollars, but still!!!).

RACKING UP COSTS: Where I hit a "money pit" was because the TWM manifold would not bolt on above my extractors. So the extractors had to be heated and re-shaped to allow more room. Then heat insulation was wrapped around the extractors to stop the petrol boiling in the carbs (the insulation cost about $135). Finally, there were all the "pretty bits" and improvements on the stock linkage kits. For example, nylon locking nuts instead of nuts + washers. Still, I think $1,300 in ANYONE'S currency is a bit steep, considering my carbs did not need venturies, chokes, etc replaced.

SOUND: Wild! I'm sure I can hear every piston firing in the exhaust note. The engine is so much more willing to rev out, and the "urgency" of the exhaust note is more reminiscent of a Ferrari than a Nissan block. My engine's peak performance is now at about 5,000rpm - peak HP and peak torque!

LOOKS: triples look great, no question. With "sock" air filters (stuck on over each of the six air horns) it looks like a thoroughbred racing machine. I'm sure with a cold air box the exhaust note would be a bit milder, although the look is certainly not as "raw". Of course there are also the looks of passers by, who turn and stare when they hear me coming!

:sick: FUMES: Yup, if you had any fumes before you'll CERTAINLY have more now! I have to divert my exhaust tip away from... well... everything!!! I need a 10-foot extension (with separate wheels), so that my exhaust fumes only bother cars in neighbouring suburbs!!! Right now my car certainly does not pass the "girlfriend" test - i.e. my girlfriend gasps and chokes and begs me to pull over!

OTHER STUFF: You won't need your choke anymore, as it's like having six carbies on your engine - instant feed whenever you need it. But you might need shares in an oil company?! I might drop another thread on that later, once I know how the gas mileage has been effected (it's too early to tell). But with all those extra fumes, I can only guess that (a) it's running richer, or ( I'm using WAY more gas!

CONCLUSION: I'm done gagging at the cost of this exercise, and now I have nothing else but enjoyment. I always wanted six air horns sucking air into my engine, so I'm extremely happy with the result. Suddenly I'm driving a 150mph car! Now that's a sports car baby, yeah!!!

[Chino 240Z]

Just plain SICK I say!

Oh, and the girlfriend approval?

NEXT!

[Gav240z]

Im curious if you looked into the Fuel Injection system that uses multiple throttle boddies like those at http://www.speed-technology.com/efi_intro_animation.html

I would like to venture into the idea of tripple carbs but I think it might be better off getting it fuel injected.

Any thoughts.

[moyest]

Well, after a weekend of burning up the streets with the new triple Weber set-up, I am happy to say the fuel efficiency is not too bad!

Sure, if you drive the car with a lead foot you'll go through a tank of gas in no time, but just cruising the highway at legal speeds seemed fine.

I hate to mix metric with imperial, but I travelled about 220kms at 65mph over two days. I couldn't help knocking it down into third gear and stomping on it a few times and still the fuel consumption was good.

I went through appox. 1 full tank of gas after travelling about 315kms. I've got NO IDEA what that equates to in miles per gallon, but I know it's not much worse than when I was running a standard set-up.

SUMMARY: WHO THE HELL CARES!?!?!?! It's a sports car, man! Built to be driven! If you're really that worried about getting good gas mileage, buy one of those Toyota hybrid petrol-electric contraptions that does 1,000kms on the smell of an oily rag!

[ozlime240z]

Originally posted by moyest

I wish I had a photo, but it's too soon - I only got my car back from the mechanic last night... Brand new TRIPLE WEBERS on a TWM manifold, fitted and tuned~

A couple of photos would be great.

DYNO-TUNING: This is a must. You've got to get it right the first time, otherwise you'll have some expensive engine hardware that doesn't add to performance at all. The extra fee for time spent on the Dyno is minimal, compared to the cost of having to have them constantly re-tuned if you get it wrong.

Couldn't agree more! I have a Triple Delhorto setup and once they were tuned properly I haven't touched them for 14 months since! Here's a photo of my Triple Dell 44 setup

http://www.classiczcars.com/photopost/showphoto.php?photo=2105&size=big&password=&sort=7&thecat=500

:mad: MECHANICS: Obviously they have to have a Dyno! But it also helps if they've set up a Z before. Again, by sheer LUCK I used mechanics who knew their way around Z cars. The workshop owner's son drives a modified 240Z (turbo), and the owner drives an even MORE modified 240Z (RB26 engine from Skyline GTR). BUT, they were expensive. I must admit I felt "ripped off" when I got the bill for $1,300 (that's Australian dollars, but still!!!).

Hmm.... that shop sounds familiar. They wouldn't happen to be at Woolloongabba in Brisbane would they? That's where I took my car to get tuned. They did an excellent job. For a dyno tune and re-jet (the PO got it wrong) cost $AU380. I don't consider what you got charged excessive if they did a good job. Figure it out, how long did they have the car, how many hours did they work on it and what was the invoiced labour rate?

RACKING UP COSTS: Where I hit a "money pit" was because the TWM manifold would not bolt on above my extractors. So the extractors had to be heated and re-shaped to allow more room. Then heat insulation was wrapped around the extractors to stop the petrol boiling in the carbs (the insulation cost about $135). Finally, there were all the "pretty bits" and improvements on the stock linkage kits. For example, nylon locking nuts instead of nuts + washers. Still, I think $1,300 in ANYONE'S currency is a bit steep, considering my carbs did not need venturies, chokes, etc replaced.

That's allot of work you've got them to do... if you wanted to save $ you could have done it yourself....

SOUND: Wild! I'm sure I can hear every piston firing in the exhaust note. The engine is so much more willing to rev out, and the "urgency" of the exhaust note is more reminiscent of a Ferrari than a Nissan block. My engine's peak performance is now at about 5,000rpm - peak HP and peak torque!

I agree triples are great, Mine are on an L28 and don't peak quite that high. A scan of your dyno graph would be nice, here's mine.

http://www.classiczcars.com/photopost/showphoto.php?photo=2291&password=&sort=7&thecat=500

LOOKS: triples look great, no question. With "sock" air filters (stuck on over each of the six air horns) it looks like a thoroughbred racing machine. I'm sure with a cold air box the exhaust note would be a bit milder, although the look is certainly not as "raw". Of course there are also the looks of passers by, who turn and stare when they hear me coming!

Tripples do indeed look awesome and sound awesome!

:sick: FUMES: Yup, if you had any fumes before you'll CERTAINLY have more now! I have to divert my exhaust tip away from... well... everything!!! I need a 10-foot extension (with separate wheels), so that my exhaust fumes only bother cars in neighbouring suburbs!!! Right now my car certainly does not pass the "girlfriend" test - i.e. my girlfriend gasps and chokes and begs me to pull over!

Get out the silicon sealant! I've found opening the footwell vent and trying to keep the windows closed is a huge advantage. Of course my 240Z is also AirConed

OTHER STUFF: You won't need your choke anymore, as it's like having six carbies on your engine - instant feed whenever you need it. But you might need shares in an oil company?! I might drop another thread on that later, once I know how the gas mileage has been effected (it's too early to tell). But with all those extra fumes, I can only guess that (a) it's running richer, or ( I'm using WAY more gas!

Yeah triples don't really seem to need a choke, they don't like accelerating with high throttle until they are warmed up but they will start and run fine.

My fuel consumption with the triple 44 Dells is:

12.75 L per 100km or

18.45 MPG in the old talk

That's averaged over 6000kms (3700 miles). Not to bad really. Just under the fuel consumption of a stock Commodore!

CONCLUSION: I'm done gagging at the cost of this exercise, and now I have nothing else but enjoyment. I always wanted six air horns sucking air into my engine, so I'm extremely happy with the result. Suddenly I'm driving a 150mph car! Now that's a sports car baby, yeah!!!

What's done is done, no use crying over spilt milk. Just enjoy!

OzLime240Z

[moyest]

THanks for the comprehensive reply.

I was a bit confused by my DYNO results, and by YOURS ozlime240Z.

My print-out suggests I have something like 523NM of torque! And yours suggests 581NM! That seems WAY too high, considering that a 7.0 litre Dodge Viper V10 has about 500-odd??

Can that be correct??

[Travel'n Man]

CONCLUSION: I'm done gagging at the cost of this exercise, and now I have nothing else but enjoyment. I always wanted six air horns sucking air into my engine, so I'm extremely happy with the result. Suddenly I'm driving a 150mph car! Now that's a sports car baby, yeah!!!

Some of these older threads are great............damn, it makes me want to order a triple shot and get in the garage!!

[Hakosuka 69]

My first response on this site is this old old thread. You can probably see my opinion of triples by my profile pic. LOVE THEM!! Wouldnt drive a L motor without em. I prefer the Mikunis myself, seem to stay in tune much better.

[FoxyZ]

The triple webers look great, but considering the work that has gone into these, I am thinking of going back to SUs. I have a 1970 240Z with oversized flat top pistons and mild cam. I would appreciate any thoughts.

Jeff

FoxyZ

[d240zx2]

The sexy look of your Z DEMANDS triple carbs!

[Curtis240Z]

Im curious if you looked into the Fuel Injection system that uses multiple throttle boddies like those at http://www.speed-technology.com/efi_intro_animation.html

I would like to venture into the idea of tripple carbs but I think it might be better off getting it fuel injected.

Any thoughts.

Individual throttle body (ITB) fuel injection is better than triple carbs, but then again it is more work and more money. Plus you need to be able to make you fuel maps or pay a tuning shop more money. I had triple Mikuni 44s (that were running great) and made the jump to ITBs and will never go back. The throttle response is SO much faster and the high end is even better because there are no chokes/venturis to reduce the flow. You can see a couple of pictures in my Z photos.

Edited July 2, 2010 by Curtis240Z