Probably jetted for a 2.0, it will struggle all the way through the rpm range. The primary jets are the critical fuel supply point. Look at the plugs, they should tell you how lean it has been running.Originally Posted by pennyman1
Probably jetted for a 2.0, it will struggle all the way through the rpm range. The primary jets are the critical fuel supply point. Look at the plugs, they should tell you how lean it has been running.
What are all the factory jet sizes? I still have the 1st knockoff clone I got. I could use the jets out of that carb?
UPDATE***
(geezer - The plugs looked lean from the 1st clone i had on here. I will clean them with carb cleaner and a light wire brush and recheck them.)
So i took the tops off both carbs and the jets were all the same, except for the air jets(? ones up top) were reversed from carb to carb.
Here is what they were when i pulled them apart;
Idle
Primary - 60
Secondary - 50
Main jets
Primary - 137
Secondary - 140
Air jets
Primary - 165
Secondary - 160
* These two were swapped 160/165 in the 1st clone.
I swapped both idle jets from the knockoff to the rebuilt weber thats on the truck now and it made no difference, but the knockoff idled much better about 2 turns out (idle mixture).
So for giggles I replaced the original 60 primary idle jet to a 50 from the other carb, and presto, perfect idle at 1-3/4 turns out instead of all the way in. Im thinking the knockoffs idle jet passage probably wasnt flowing more than what a 50 or 55 idle jet would, even if there was a 100 jet in it, if that makes sense.
I also replaced the primary main jet from 137 to a 140. so now both main jets are 140/140 instead of 137/140. This made what I can only call, a massive difference in part throttle acceleration. This was a much needed improvement, now I dont have to mat the pedal to accelerate with normal flow of light to light traffic.WOT didnt change much because I didnt mess with the secondary main jet (just have 2 137s and 2 140s).
It is very interesting how with the same exact jets, that they ran SO much different between the two. I have however come to the conclusion that this is a real weber body, with some of the parts being clones. I can only assume that it has been remanufactured at some point with inferior parts.
Does anyone here know what jets their redline weber 32/36 dfav came with from the factory, so I can compare? I cant get a solid answer from google.
So now you see why these knock offs are garbage. The metering galleries in the carb body aren't milled properly and it strangles the flow needed for the jets to pick up and atomise the fuel. The typical symptom is this lean/rich paradox that shouldn't exist under normal conditions.
Yes it is extremely frustrating. There are other issues that need attention but id like to have the engine running well before I go digging into other things. This is really slowing me down. lol
Now I'm debating on just buying a jet kit or biting the bullet and buying a new kit from redline.
These are the recommended jets for a 2.0 but the difference for the 2.6 will be in the primary/progressive being slightly bigger - http://www.mightyram50.net/vbulletin...ll=1#post44111
That is some good info. Thanks again.
I've been playing with this thing all evening. I've got it running pretty good. It is running the best it ever has, all the way around. Idle is smooth, snappy revs even after sitting at idle for 10 min. Changing the primary idle and main jet massively improved low end torque and worked wonders for throttle response and idle quality. It breaks the tires loose from a dead stop without using the brakes. Something it would not do before. Im at 1-1/2 turns on the idle mixture screw now.
I think i may just get a jet kit to try to squeeze a little more out of the top end, and I will be happy. I feel like trying to get my money back from this carb is a lost cause. Id rather not spend another $300 when this one is super close to what I expected.
You guys helped a ton with this. Thank you all so much!
Check for my upcoming post about setting valve lash. Its got some valve chatter on down revs and holding the rpm steady at higher rpm. Thinking it needs adjusted.
Out of curiosity, did you have a crack at using my tune method? I'm stoked that you have got the Weber working well now.
I can only add my experience, I'm not an expert and I'm still working out the bugs
atm I have
55 idles
145/140 prim/sec fuel
170/175 prim/sec air correctors
4g54, extractors, wideblock industrial bottom end, forged industrial crank, forklift oil pump (no balance shafts) m6 head, ported mani.
7 deg btdc at idle, roughly 32-35 at WOT
Ive been told by a few old petrol heads, but its all just here say so pull me up on any of it:
To run both idle jets the same size.
Fuel jets are large steps, air correctors are to fine tune.
Dropping a step in air correctors richens it, larger leans. vice versa for fuel jets.
Check and play with your timming every time you change a jet. At idle and WOT
Make sure you throats are as closed as possible when idling, and your throttle cable isn't to tight.
Go by what Redline/weber documents say about best lean mixture, experiment from there on
4g54s, being they are all torque, the secondary acts as a supplement to the primary
Even stock identical motors may need to be jetted slightly different
Its a 3 way balance of idle and WOT timming, idle jets, prime and sec throat jetting to find smooth transition, power and economy.
My ute was in storage for a few years, pulled it out and it had a noticeable lack of power, dieseling, bogging, allsorts.
Turns out my vac advance diaphragm was leaking, so I had to replace it.
In Australia misti bits are still plentiful (although no one really wants them) and theres a myriad of heads, piston, crank, dizzy and cam/valve train options.
I found between the 4g62, 4g63, 4g52 and 4g54 depending on the type of vehicle be it passenger, commercial or industrial, some had different numbered armatures into the dizzy, and I'm guessing this is how much the vac will pull the internal advance.
I know I have an old turbo hall effect dizzy somewhere, and I'm pretty sure that retards the spark as opposed to advances...
I'm yet to have the time to play around, and theres not too many out there left with the knowledge.
Make sure your diaphragm holds constant vac ^_^
I wish i could just throw a fitech plug and play efi setup on this. This would be sooo much easier. Im an efi guy. lol I tune my own race car (turboed sn95 cobra) with a laptop, but im a newbie with carbs. My limited carb experience has been on holley double pumpers. Same concept though.
I think the primary, and idle jets are pretty close. The secondary jets need some tuning still. I can feel the spot in the pedal when the secondary barrel starts to open up. Past this point isnt a huge difference from just the primary barrel being open. Like I said before, part throttle (primary barrel) is running very well.
Geezer, I havent yet. I still need to buy a cheap tach before I can do that. Its still at 7btdc at idle with no vac to the distributor. Would you recommend your method over buying the correct weights and springs for the advance? Or is this method just to get close with the factory springs and weights?
The Weber is a tricky beast. It generates more internal vac than the asthmatic Mikuni and as a consequence, ramps the advance. Seeming you can pick the point where the secondaries open up, this is the gateway to midrange power. If you can hold the engine at that point and swing the distributor through advance/retard and take note of where the rpm increases, then bump it back a tiny bit, this should improve engine performance. It does come at a price by affecting low down but you can't have your cake and eat it too. The engine needs a max total of 32-35 degrees advance when it's on it's feet. You will find it's base advance is going to be more than 7 degrees, but it will also run better. I think the amount of cash you'd throw at re-dialling a distributor would only be justified for competition.
Hello! I'm having the same possible jetting issue. 89 ram 50, 2.0, automatic with a brand new weber DFEV. Idle speed screw set at 1 1/2 in and mixture screw at 2 out. It barely idles enough to stay alive. I still need to check the timing, but it feels like more than that. Who knows about re jetting?
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