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Good day ladies and gents Wondering if anyone can help. My Ra23 celica passed compliance, and now working on getting it to drive properly. currently setup with 40phh mikuni sidedrafts with 18r-geu engine converted from EFI. When the celica was fresh off the boat from Perth, it was running on 3 cylinders and had no spark on cy 1. with fouled plugs. as black as you can get them. I put in new ignition coil, leads, dizzy cap and rotor, spark plugs. had it running on all 4 cylinders to adjust timing. I adjusted the timing to slightly advanced as it wasn't running well in neutral. in retarded timing, the engine gagged like it was gonna stall... With abit of advance timing, it idled and rev'd fine but under load there were some bangs and pops especially uphills. Sparks started to foul up again.. only cy 3 plug was burning ok. Carbs have not been tuned yet which may be one reason why this girl ain;t running properly. If anyone who knows what they are doing with carbs and can lend me a hand, I am happy to pay in beer Any other advice on where I should look/check from here would be great. Thanks Min
I have a Weber 32/36 downdraft and i want to delete the power bypass circuit diaphragm on the side if that's what it is most race prepped Webers seem to have it removed but I'm not sure what exactly needs to be done like block a hole or something bypass something has any one done this?
This is essentially a abridged version of many books and the minds of people I have been picking over the last few weeks trying to sort out my carbs. As I finish mine, I'll post up more. People often complain that SU carbs are hard to tune. This is not necessarily true, however tuning worn carbs is nigh on impossible. Below is a list of the few things that commonly go wrong after extended periods of time. All this is assuming that your ignition, valves etc are in reasonable condition. This is in order of easiest things, what you should be checking first. Symptoms: Running too rich or too lean throughout the rev range, will make it hard to tune. Problem: Incorrect float level Diagnosis: Hold float upside down, measure gap with a drill bit or calipers, space to factory specs. With dual carbs, the floats must be the same level! Not like the ones below! If you want to get fancy, turn the ignition on until the fuel bowls fill up and measure them with an eyedropper or something Note: If the float appears to have stuff inside it, replace it. Checking the levels with a drill bit: Some terribly balanced floats :/ Symptoms: Fuel starvation and lack of power OR overflowing float and flooding/running rich Problem: Sticky float jets (also called needle valves, ball and needle valves) Diagnosis: Take the float out, play with the needle valve, if it doesn't move smoothly, take it out and replace. Symptoms: Uncertain idle (it never seems to reset to the same idle speed), lean idle and run-on. Problem: Spindle bushing wear Diagnosis: If in half and full throttle, you can see up and down movement in the spindle/throttle butterfly, the bushes are worn and must be replaced. Give it a wiggle! Problem: Worn needle Symptoms: Surging at constant speed Diagnosis: Surging at a certain throttle position under load indicates a wear in the needles corresponding to that throttle position. Any visible ridging means the needle must be replaced, however the needle could be worn and the wear not able to be seen. Problem: Worn jet Symptoms: Constantly too rich Notes: While you can just adjust this out, there comes a point where the jet is starting to poke into the throat too much and push the piston up. Time for new jets. Other checks you should do: Remove the piston damper from the top of the vacuum chamber, and lift the piston. It should fall back with a clunk. If it doesn't, you need to centre the jet. Workshop manual or youtube has plenty of info on how to fix that. <Stuff about piston levels> If you don't have any of the symptoms associated with a problem, your car runs OK, then it's probably fine. Unless you want to spend tons of money chasing that last 0.259 hp, don't bother replacing everything. For further reading, speed sports motorbooks has a "Tuning SU carburettors" (pdf available online) that has excellent (dis)assembly instructions. "The SU carburettor: High-Performance manual" by Des Hammill is also a reasonable reference on how things work. There are plenty of tuning articles out there, however they will be folly if they are improperly set up and/or worn. Haynes also has a manual, but I haven't found a copy of that yet.
Hey guys, I've decided the next thing my car needs is a better carb. It's a 1300 mkII escort currently with the stock carb. I'm planning on eventually dropping in a 1600 so don't want to get too carried away now, but could definitely do with a bit more power and a carb seems like a cheap and easy upgrade which could eventually bolt onto the new engine to begin with. I've done a bit of research and it seems that a Weber 28/32 or a 32/36 is probably my best bet. Anyone got any advice on this? Do I need a new manifold, or could I get an adaptor milled up to bolt onto the existing one? If I do need a new manifold, is just any crossflow Weber downdraught setup suitable or do I need a certain type? I was hoping to spend somewhere in the region of $200-$300, is this a realistic figure? If anyone has anything suitable for sale pm me please. Any guidance or tips would be awesome.