TheSamba.com :: View topic - What do you guy find wrong with the Chinese IDF copies?

Tue Jun 16, 2020 4:05 am

First time I start a thread here, - I think :roll:

Every once in a while we run into the discussion of issues with the chinese copy Idf´s. - I am aware that some of them actually works well, but to me it seems that the majority of them have issues. Just last week I had to toss a set of 44´s and replace them with some rebuilt Spanish.

Here is what I see most often, - (generally Empi IDF´s gen II & III excluded):

Discharge orifice for aux venturi in the wrong place, typically too low, and/or uneven from side to side.

"Something" wrong with the idle system, so you cannot control AFR in the cruise area. - Almost always way too rich. (Havent found out what it is exactly)

Seat surface angle for the main jet not correct, so the main jet is not sealing correct.

Slop at the throttle shaft bearings, - although that seems to become rarer.

Butterflys not closing correct because the angles on the butterfly are wrong.

Venturies have a wrong shape. (Means less unless you are chasing the very last. But still)

What do you guys see? And have you found the problem with the idle circuit?

T

Tue Jun 16, 2020 5:03 am

Gen 1, Porous castings.

Tue Jun 16, 2020 8:15 am

the only issue I had with mine were the booster vents not sealing to the main body and not square to the body, so i milled them flat&square and added gaskets to that joint. wow what a differance that makes. I think I had to jet down 2 idle size and 1 or 2 main sizes and oh so smooth transition now. just stick a carb cleaner straw down the air jet and spray a little and watch how bad the booster vent joints leek!! add gasket and no more keek. a lot less time for the fuel to be pulled and all 4 holes get the same signal. I wish i had done it years earlyer, other than that I had well over 150000 trubble free fun zinger miles with them on 1874cc,2332cc and 2028 cc engines when I sold the car. it was a true daily driver.in town& outa town my only car since 2002 till 3 months before I sold it last year .

Tue Jun 16, 2020 8:20 am

They seem to wear out much quicker after 2-3 years where I have use the same set of Webers for 25 years.

All the jets are not accurate sized.

The linkage and air cleaners that come in the kits is just pure junk on all the China clone carbs.

Tue Jun 16, 2020 8:30 am

vwracerdave wrote: They seem to wear out much quicker after 2-3 years where I have use the same set of Webers for 25 years.

All the jets are not accurate sized.

The linkage and air cleaners that come in the kits is just pure junk on all the China clone carbs.

This is the number one reason I don't buy those kits. The carbs are generally fine but I flat out refused to use the linkage. I ended up buying geniune redline weber and by that point, the price was almost the same as buying the redline kit.

Now, I just make it easy and only use the redline kits on all my engines.

Wed Jun 17, 2020 8:38 am

I've only messed around with 4 IDF 44s. Two of which I'm using on my Porsche 2 liter engine with 32mm Venturi's. Which was extremely difficult to jet. The other two I also used them on the Porsche engine but with the original 36mm venturi's. These were extremely easy to Jet correctly. I wonder why!🤣
What I found is the following.
All 4 carburetors, the Jets were incorrect. All also had the throttle body plates were not calibrated correctly, they would not close all the way. The easy fix was to loosen the throttle plate screws on the throttle shaft and then close the throttle by putting more pressure. When you do this you'll see that the throttle plates will actually move and rearrange themselves in the correct position and close even further. Then retighten and you're done. 🙂
I had to replace all the throttle bearings on all 4 IDF's. They were just too loose, they were all garbage. One IDF has a fuel weeping problem. For some reason in the morning the IDF has no fuel in the fuel boal.🤔 I still haven't figured that one out so I'm not using it, but runs wonderfully.
No problems on the IDF circuits did I can detect. All four IDF's that I have have a perfect transitioning between the idle and the main jet. Maybe I just got lucky.🙂
I also found that the interior was extremely dirty with metallic flakes probably aluminum due to the Machining, but yeah... you should not run these Straight Out of the Box without a thorough cleaning. All 4 needed a slight adjustment on the fuel pump adjustment nut just to remove the slight hesitation all 4 had.. but other than that the darn things run great with no hesitations. Again I think I got lucky.

Wed Jun 17, 2020 1:38 pm

Motor7710 wrote: All 4 carburetors, the Jets were incorrect. All also had the throttle body plates were not calibrated correctly, they would not close all the way. The easy fix was to loosen the throttle plate screws on the throttle shaft and then close the throttle by putting more pressure. When you do this you'll see that the throttle plates will actually move and rearrange themselves in the correct position and close even further. Then retighten and you're done. 🙂
I had to replace all the throttle bearings on all 4 IDF's. They were just too loose, they were all garbage.

So this is timely for me as on a whim (because I just realized they exist) I bought one of the $73 40s and it came last night. My inspection was cursory, and I don’t even have something to put it on but I’m amazed. Yes dirty, we’ll see what comes out in the ultrasonic, definitely gray residue and some metal flakes. The casting and machining are amazing to me, on the surface no worse than the Spanish Weber I have sitting next to it. Particularly I figured the progression ports would be garbage but sure seem nice enough in appearance. My jets all measure fine (as symmetry goes) though I didn’t look at or care what they are marked, measure 2.0, 1.2, 0.55 air, main, idle respectively. I had read about nightmares about emulsion tube machining, mine look as good as Weber.

Float installed/adjusted by a drunk blind monkey. 8) My throttle action is crisp with no play and the plates center and close perfectly. I will say the plate screws have massive heads with split lock washers and are not peened nor threadlocked. I will trim those quite a bit, remove the washers, threadlock instead as they really stick in the flow. I had read about poor contour vents, mine appear as nice as Weber (and came 28s.) Now admittedly I haven’t run it, and I’ll likely be cussing 2 months from now when I do but as a one time mechanical design engineer and still hobby machinist I’m amazed this came to me for $73, with several arm choices included, reasonable base gaskets, reasonable velocity stacks. Enough to risk buying another so they will hopefully be matched in their jetting. I have plenty of manifolds and old CB hexbar linkages so with air cleaners I’ll be $200 into a running set.

I will take one more step to these as a precaution after some poor luck with a few $10 Chinese small engine carbs and Alodine the bodies as I’ve had small engine ones that looked/performed beautifully new but corroded within a month externally in only moderately humid indoor storage and internally from fuel.

I will take some pics this weekend of the $73 option vs the real Spanish Weber as I ultrasonic it and post pics.

Wed Jun 17, 2020 2:47 pm

is this also with the Empi ict 34 kit? currently running that setup drives waaaay better than stock but hey I came from an 31pict-3 on a 1600. never driven one with webers, neither real nor reps.

Wed Jun 17, 2020 2:50 pm

MitchS046 wrote: is this also with the Empi ict 34 kit? currently running that setup drives waaaay better than stock but hey I came from an 31pict-3 on a 1600. never driven one with webers, neither real nor reps.

You would be please with the unleashed additional 10-15 HP....

Dale

Wed Jun 17, 2020 2:52 pm

I just got a $211 set of 48 IDFs. I haven't opened the tops yet. One thing I do notice is the throttle shafts seem a tad loose.

Wed Jun 17, 2020 3:57 pm

I wonder why mine didnt wear out ? what si there to wear out?? the stacks need reshaping so they do not eat the filters.after that the filters work good and no issues,of coarse I dod always run outer wears on mine so that may of helped as well as I know how to clean a filter and not fuck it up. I also sized my own jets. I bought a pile of 115 mains and sized them to what I needed.
Ive installed somany new carbs in my life time I cant even to begin to think of howmany. race cars, street cars,trucks,race trucks, std passanger cars and more.I dont recall ever having a carb out of the box that was "right" or bolt on ready to go. I think tomany people think that carbs are a fix for whate ver ails thier vehicle without any work or tuning. IMHO like everything else most issues are inflicted on the carb...by somebody.and somebody will never addmit it.and probably never learn.
yes some carbs do have issues.and first run stuff is usually the worst.

Wed Jun 17, 2020 8:13 pm

So far I’m pleased with my 45 emportos. But I’m running a mechanic. Advance distributor, so keep things on the rich side.

Wed Jun 17, 2020 10:20 pm

The competition is so high for these IDF carburetors that all that is left is tier 2 quality. Nobody bought enough of the Tier 1 quality from China, They were selling them, but everyone shopped price, competition heated up, so they sell lesser quality idf's only now for cheaper to answers everyones demand for lower price. Thats whats wrong with them. But yes, it would be good to log the LATEST details from what people have been having. (Not from carbs of 5+years ago).

Tabari, would love to see how yours turn out. How bad are those throttle shafts?

80% of the no name idf's come from the same factory in Taizhou(Pro-nounced Tai-Joe) China. FAJS/EMPI and anything with a name on the carburetor itself will come from different factories.

A big heads up, The same thing that happened to the idf clones is about to happen to the IDA clones that have been out for only a year. There is tier 1 great quality IDA style carbs that are out, and now there is tier 2 junk ida's in the mix because people ask for lower prices no matter what, price being the ultimate factor. Sellers are lowering the prices and making deals with the distributors/factory to sell the tier 2 carbs instead. They look the same on the outside. The price comes down, you sort ebay by price, they look the same, so you think, man, this one is a little cheaper, it must be fine, bam, you been sold. You turn a blind eye to the fact that the seller has 97% or whatever horrible feedback and hope for the best. The crazy thing is, its not enough that they are HALF the cost of webers, people have to get the price halved again, thats where the problem is.

For those of you that have cheap idf's and take them apart and they are nasty, things messed up, I can guarantee you that these ida tier 1 clones come from the same factory as yours, but look at the finish and cleanliness inside and you will see the difference between tier 1 and tier 2 and see why your carb cost $75-$100 each and this one is $300 each.

This is out of the box:

These I purchased 3 sets, as they are tier 1. Kept 1 for myself, Sold 1 set, and still have 1 set left. I did this simply cause i seen the writing on the wall. I located the factory in China, My wife is Chinese, and able to go back and forth with them and make sure i get tier 1 carbs while interpreting some other in/outs of the industry that is, lets just say unique to the culture.

The future of IDA clones will end up like IDF's in no time flat. They will ALL be tier 2 with issues just like the idf's pretty quick.

The exact ones i got didnt need anything. Connected gas lines, adjusted mixture screws and ripped. Perfect bearings, throttle shafts, not a speck of shavings, metal, or anything. I want to show this, because Chinese can make anything they want, with great quality, if people ask for it and demand it. But there is a shitload of people that say, "half the price of webers is still too much, i need them to be cheaper then that before i will buy them" . For this reason, the companies will crank out the Shit just for them.

Fri Jun 19, 2020 9:19 am

When I need carbs I buy old IDF's in poor but rebuildable shape. Most of the time am able to make them run like new. Cheaper than buying a new China clones and will last a lot longer. Dan

Fri Jun 19, 2020 9:33 am

Maybe around where you live Dan. Here they are just about gone, and when we locate some, half of them are corroded so bad that they are not worth spending time on.

Fri Jun 19, 2020 10:43 am

Alstrup wrote: Maybe around where you live Dan. Here they are just about gone, and when we locate some, half of them are corroded so bad that they are not worth spending time on.

x 2 :cry:

Mon Aug 17, 2020 8:57 am

DANG!
It happened.
This morning I had a customers 2165 type 1 on the rolls. CB 2288 cam, 044´s that I have ported w. 44/37,5 valves in proper seats,, 10-1. Magnaspark dizzy w. HV coil and CB Black box. A1 1 5/8" sidewinder with 2 in line 2½" mufflers, one on each side of the engine,,,,,,, AND Fajs 44 IDF´s.
Initially I was like, ohh well, that´ll take the full morning and then some if we can even get the thing to run decent. BUT, to my great surprise it was not so this time. After intial setting of the float height to 12 mm. they responded very well. A couple of cruise pulls and we decided on 50 idle jets. and went on to the main system. This particular engine is a little mean, it pulls HARD for what it is. I ran into te typical IDF afr dip in the 2900 -3400 rpm range, so I decided to drill 1 hole in the E tube second row. That made it significantly better, but not quite where I wanted it. So I replaced the Chinese venturies with a set of my own that have a better and more precise throat and it was just about spot on. I could maintain AFR in a 12,4 - 13 window on WOT from 2500 to 500 rpm after max hp. Amazing. This particular set of Fajs is the best set I have ever worked with. They were so easy to dial in that I almost came to think Dellorto quality... No, I did´nt say that. But out of the maybe 25 engines with these copy IDf´s that I have had on the rolls these were by far the best. Generally it is about 20% that will never work, 60% that can be made to work with some persuation and 20% that are fairly easy to get to work. Now I need to change that to 18% and 2% that works well :roll: :D
Ohh, for the numbers people it pulls 172 hp @ 6300 (Din) and 232 Nm peak torque. I wohnt post a data sheet because it is not "my" engine.

Mon Aug 17, 2020 9:21 am

FreeBug wrote: Alstrup wrote: Maybe around where you live Dan. Here they are just about gone, and when we locate some, half of them are corroded so bad that they are not worth spending time on.

x 2 :cry:

X3😭
Maybe they are just gone in Europe?🤔

Mon Aug 17, 2020 9:49 am

I built a 1986cc bus engine with real Spanish IDF's, brand new from CB. They worked pretty good. Slight transition hesitation that was later worked out
.
The next engine was a budget 1835cc bus engine. I used some no brand china IDF's with CB linkage, and they worked awesome. Same amount of crap in the float bowl's, and the floats were just as far off when received as the real ones.

I have a shelf full of decent rebuild-able 44IDF's, and various DCNF's. They have been there for years. No reason to rebuild a mystery carb when you can get these now. Add a $200 CB linkage and manifold kit, and for under $400 you have a near perfect set of very usable carbs.

Brian

Mon Aug 17, 2020 12:22 pm

The girl I met when I went out to watch the off road buggies has been talking about buying a set of the low cost carbs from amazon or e bay.

Anyone know what exactly to look out for when trying the ones around 90 to 120. I noticed they do have some with names but I don’t know which might be better or worse.

I have Empi copies that run good and a few sets of real Webber’s that have all been flawless so other than telling her to just get what I did, I can’t offer any help. But know I will be the one dealing with helping to get them to run correctly.

The last ones she showed me had a name anglewide and were 44 copies.
I have a good linkage I would be able to give her but hate to see her waste any money.