Dual carb on a 79

[fiat218]

my empi has not had one problem
each to there own

[MrJD]

And you're an EMPI believer right Mark?

Not sure of the tone you're taking here.
But if you aren't already aware if it. Mark has been and is a huge help to all on this forum.

Um, problem? We are all in the same boat here.

Mark knows what he is talking about, and sells the product; thus why I am asking him. I tend to trust the opinions of people that know more than me, and Mark is one of those people. If he says the Empi is an acceptable stand in for a perfect factory weber, then that is good enough for me.

[RoyBatty]

No problem,
Just the intricacies of text only comms on the internet.
The post I quoted you on looked as though there could have been some slight bit of venom with the use of the term,
"EMPI believer".
I was just asking.
And as you have probably noted, the EMPI should serve you well. Unless you have emission restrictions that prevent you from using it.

[bradartigue]

The 32 ADF is a bit restrictive on a 2.0 isn't it? My impression was that they changed from a 34 to the 32 to try to get the cars past emissions issues on a 1.8... so the 32adf isn't necessarily a "great carb"... it is simply better than the POS the 79 came with stock.

that being said, you will have trouble finding a 34adf whereas you can buy a 32/36 brand new (For not much money either)... which tells me you can get parts MUCH more readily and, as already pointed out, you can get one new with the right linkage and jetting for your particular set up.

Is a 34 really better than a 32-36? Air volume should be nearly identical on the face of things (at WOT)... but I bet the 32-36 will get better gas mileage when you're not running it hard.

Also, I have read that the 4-2-1 exhaust is just as good as most headers out there. I find this kinda hard to believe... anyone had both and feel like commenting? I tend to find that all cast manifolds are a bit restrictive by header standards.

On the first point, yes, the 32 is more restrictive than a 34ADF, but it also more available and has a hell of a lot more power than the ADHA the car came with. So it is a good solution for a nice driver, it's not a performance carb. 34ADF was a performance replacement from the get-go, and if you dare find one, the 36ADL is just awesome.

On the second point, you can buy them all day long new, but they're expensive - $600+ - and the relative difference between it and the 32/36 DFEV isn't worth the $.

On the third point, it is a completely different carb design, the ADFs (and ADLs, ADHs) are like a carb body sitting on a throttle body vs. an integrated compact unit, the performance characteristics are different, the torque curve you get is different. The D series is a 1950's design, the A series is a 1970's design, the seat of the pants difference is in there. Is it enough to justify the cost difference? I think so...but we're talking miniscule personal preferences here.

The 4-2-1 is a header. Either that or most of the tinny junk sold as "headers" are just manifolds with tubes poorly welded to them. The 4-2-1 is a nice improvement over the 4-1, mainly due to the abrupt stop-drop-and-turn of the 4-1 vs. the gradual curve and collection of the 4-2-1. Very, very, very few of us will ever have motors modified to the point that a header is even necessary; if you like the sound effects then get one. And a twin-tip ANSA and fog lights. In two years or so you'll be installing a 4-2-1 and a single tip exhaust and find the performance is identical, the note is much sweeter (because the stock stuff sounds Italian).

[bradartigue]

Weber Directs cheap carbs are also made in China, they put Weber decals on them. I expect they're made in the same factory that makes the EMPI carbs. At least EMPI is still doing R&D on their carbs and have improved the venturi boosters for better transitions. The EMPI carbs do have a one year warranty.

As for headers, I've posted my dyno results for both my Spider and X1/9 headers, proving our improvement claims. I've challenged every other header mfg to do the same and so far no other vendors or mfgs have responded

I find it ironic that the only guy here (Mark) who actually makes what anyone might deem a header is having to defend himself. I would bet most of the "headers" sold out there are leftover stock from the early 1980's, because no matter where you buy them they are all the same tinny, ill-fitting garbage. Hell most of the time the only people who get them to fit right are the vendors themselves.

The fact is that without modifications to the block or head you'll have limited positive results with a header. Slapping even Mark's header on an otherwise stock motor will provide minimal gains; you need to get more air on the input side to realize benefits throughout the system. This means something like:

A good carburetor -> on a good manifold -> on a good head -> with a good exhaust system

These days that means a rebuilt or new 32/36 DFEV or 32 ADF or 34 ADF or 36 ADF or 34 DMS -> on an 1800 manifold -> on a 1592 or 1800 or 2000FI head -> with a 4-2-1 or Mark's header

I know, people say the 2000 carb head is good, but it's to ugly and has too many holes and stuff to be good. It's an ogre. The other heads are cleaner and easier to work with.

My .02...I'm sure I'm mistaken.

B

[fiat218]

The 32 ADF is a bit restrictive on a 2.0 isn't it? My impression was that they changed from a 34 to the 32 to try to get the cars past emissions issues on a 1.8... so the 32adf isn't necessarily a "great carb"... it is simply better than the POS the 79 came with stock.

that being said, you will have trouble finding a 34adf whereas you can buy a 32/36 brand new (For not much money either)... which tells me you can get parts MUCH more readily and, as already pointed out, you can get one new with the right linkage and jetting for your particular set up.

Is a 34 really better than a 32-36? Air volume should be nearly identical on the face of things (at WOT)... but I bet the 32-36 will get better gas mileage when you're not running it hard.

Also, I have read that the 4-2-1 exhaust is just as good as most headers out there. I find this kinda hard to believe... anyone had both and feel like commenting? I tend to find that all cast manifolds are a bit restrictive by header standards.

On the first point, yes, the 32 is more restrictive than a 34ADF, but it also more available and has a hell of a lot more power than the ADHA the car came with. So it is a good solution for a nice driver, it's not a performance carb. 34ADF was a performance replacement from the get-go, and if you dare find one, the 36ADL is just awesome.

On the second point, you can buy them all day long new, but they're expensive - $600+ - and the relative difference between it and the 32/36 DFEV isn't worth the $.

On the third point, it is a completely different carb design, the ADFs (and ADLs, ADHs) are like a carb body sitting on a throttle body vs. an integrated compact unit, the performance characteristics are different, the torque curve you get is different. The D series is a 1950's design, the A series is a 1970's design, the seat of the pants difference is in there. Is it enough to justify the cost difference? I think so...but we're talking miniscule personal preferences here.

The 4-2-1 is a header. Either that or most of the tinny junk sold as "headers" are just manifolds with tubes poorly welded to them. The 4-2-1 is a nice improvement over the 4-1, mainly due to the abrupt stop-drop-and-turn of the 4-1 vs. the gradual curve and collection of the 4-2-1. Very, very, very few of us will ever have motors modified to the point that a header is even necessary; if you like the sound effects then get one. And a twin-tip ANSA and fog lights. In two years or so you'll be installing a 4-2-1 and a single tip exhaust and find the performance is identical, the note is much sweeter (because the stock stuff sounds Italian).

Damn it and I was going to get a header , but my engine will need the best one out there

[bradartigue]

Damn it and I was going to get a header , but my engine will need the best one out there

I wish I had back the money I spent on "headers" in the 90's. If you have header money, spend it instead on new tires, they'll likely give you as much of a performance increase...

Of course I'd like to have a lot of money back - like the money I spent on IDFs for a Spider 2000. Which is really what this thread was about, IDFs on a 1979. So back to the point of the thread:

I really like twin carburetors, to the extent that the only reason I owned any 70's Alfa Spiders was because of the straight-shot DCOE carburetors (and the dash layout is like flying a fighter). In order to enjoy this on a FIAT there is really only the 1608, which seems to me the only stock (operative word) motor that works well with IDFs. I had a 1438 with IDFs and it worked nicely as well, but above that...too many sacrifices with quality of idle, top end, or low end, plugs fouling, lousy burning, etc.

[fiat218]

Damn it and I was going to get a header , but my engine will need the best one out there

I wish I had back the money I spent on "headers" in the 90's. If you have header money, spend it instead on new tires, they'll likely give you as much of a performance increase...

Of course I'd like to have a lot of money back - like the money I spent on IDFs for a Spider 2000. Which is really what this thread was about, IDFs on a 1979. So back to the point of the thread:

I really like twin carburetors, to the extent that the only reason I owned any 70's Alfa Spiders was because of the straight-shot DCOE carburetors (and the dash layout is like flying a fighter). In order to enjoy this on a FIAT there is really only the 1608, which seems to me the only stock (operative word) motor that works well with IDFs. I had a 1438 with IDFs and it worked nicely as well, but above that...too many sacrifices with quality of idle, top end, or low end, plugs fouling, lousy burning, etc.

And your opinion on a 2.0 with duels

[bradartigue]

And your opinion on a 2.0 with duels

Odd, where did that paragraph go?

My view is that the 2 liter needs too much other modification to make the IDFs deliver fuel and burn it correctly. At the very least people seem to alter the ignition with a ton of static advance (and on the stock distributor they eliminate the dynamic nature of the device), which robs performance on the top end to gain a decent idle. In doing this they spent around $1,500 to make the car run worse than it did with a single carburetor. The next step is to change the cams, which better match the fuel delivery of the IDFs, and help quite a bit, but not really enough, so then you are into larger valves and/or higher compression pistons, etc. At some point you end up with a hot motor and the finicky nature of high performance modifications just so you could run twin carbs.

I'd spend the IDF money on installing a 34 ADF or 36 ADL with the 1800 intake and a "clean" head - 1592, 1800, 2000FI. I could stop there or would still have the money to get some mild head work done and maybe install higher compression pistons. The car would be more reliable, have more power throughout the entire curve (more than an IDF setup on stock for sure), get good gas mileage and probably even pass emissions if it had to.

Another perspective - IDFs are a tinkerer's toy. They add complexity to a fairly simple motor, which is something you may enjoy.

[Exit98]

Brad,

Glad you hang around here. Keep your comments coming.

[bradartigue]

Brad,

Glad you hang around here. Keep your comments coming.

Sure thing, love these cars.

[MrJD]

im not doing major internal work to my 79 2.0 any time soon. Looks like im going 32 and single plane.

[bradartigue]

Go with the bull:

http://www.ebay.com/itm/LANCIA-GAMMA-20 ... 3a4f71101f

Bolt it onto an 1800 manifold and hold on to your seat.

[fiat218]

I'm going with duels
Maybe I can do something to. My 80 and make it faster, it a 2.0

[Redline]

What is it about the 1608 that makes it work well with the IDFs? After so many years of horror stories about dual carbs, I've been amazed at how well my (Euro) 1608 runs. The IDFs have really been "set it and forget it". Apart from a tiny hiccup through 3000 rpm on part throttle, they pull cleanly and strongly, I average about 27 mpg (US), they sound great and posted quite good values on the last emissions test.