hey i am building a late model A12 with a H89 head ,mild cam ,double valve springs ,and a nice set of twin 40mm solex sideys ,but the thing is i cant find ANY model numbers or stamps on them to inducate what model they are ,so i checked google and i cant find any pics that look the same as the carbys ive got

so if i put a couple of pics up could someone identify them ?


and i have looked at the chart that chris had up in his thread (huge help for newbys)
this is what i have found in mine

Main Air Jet= 150 ,150 ,150 ,150
Main Jet= 125 ,125 ,125 ,125
bleep pipe= NA
Jet Block= 8 ,8 ,8 ,8
Pilot Jet= 55 ,55 ,55 ,55

and i dont know what the pump nozzle is or wher to find it on the carbys !

so if anyone can help me with jetting and where to get some jets ,new if possible or i can get them from some early mitsys ,and what model mitsubishis can i find them in ?

thanks for any help

ok i pulled the pump cap of the bottom of the carby to find a little (short) jet in the carby block itself ,but it says 125 on it and then on the chart chris put up it is only 40

whats going on there ?

Leave that jet alone.

You have the Type-T version of the 40PHH. Pretty sure anyway, you may want to put up a pic for confirmation.

Pump nozzles are located under the little caps which sit on each barrel between the (mounting to manifold) flange and the jet/float housing.

Unscrew the little caps with a big flat and that's where the pump nozzles are. The number is stamped on the side.

The rest of your jetting is fine, maybe a little more on the mains but that depends on what other work has been done to the motor. You would almost certainly have to back the accelerator pump right off, for it not to over-fuel when accelerating.

Have you bought a manual for these? That's the smartest place to start- an instruction book.

agreed, knowledge is everything with carbs, especially sidedraughts. Your A-series will be running smooth and hard in no time.

ok thanks chris i got the carbys on an oval port manifold and as for the pump jet i found the right ones now and they are 45


and the jet that i throught was the actualy the main jet haha ,i thought the pump jet was mounted within the pump ,but it turned out that i was looking at the bottom of the emulsion tube

so would it run with the jets in it now ?

and where can i get jets ?

oh and i pulled a sleeve out of the front of the carby and it meassures 64 mm long and 42 od and 38mm id ,is this just to retain the chokes at the back of the carby near the throttle butterfly ,which is a 30 ,does this mean it has 30mm chokes ?

Yes, it will run with the jets in it now (if you put it back together correctly).

30mm chokes are large for an A12, so it may not be very smooth at low RPM or low throttle openings.

Have you looked at our wiki article Mikuni PHH?

I think you have the type S4 or S5 so not the Type T (which are the boxy ones). Upload a picture of them so that can be confirmed.

Accelerator pump;

Keeping in mind your carbs may differ only slightly from mine I’d be confident in saying that the first thing to look at when fitting these is to adjust the pump accelerator to its lowest possible setting. You do this by adjusting the con-rod to the little facet pump on the bottom of the carbs, there should be a thread on the con-rod and a small sleeve that sits over the thread, you can screw or unscrew that sleeve to get different settings (micro adjustment). There is a macro adjustment which is at the other end of the con-rod and this is by three set holes, highest being the high delivery and the lowest being the lowest delivery. I have adjusted mine so that it moves ever so slightly (maybe not at all).
With your size 40 jets and a the accelerator pump at mid-setting you’ll find the duration of the fuel injection from the pump nozzles will be quite long and the delivery too heavy or excessive. Seeing as size 30 nozzles are hard to find, your best bet is to back the pump right off. When driving the car, the excessive fuel delivery will typically result in the carbs making a barking (bap, bap, bap) or the engine will simply begin to groan like its being lazy and eventually it’ll start the barking.

Synchronisation;

Just to add to the difficulty, when the carbs are out of synch this barking/stuttering will also happen.

Check that there is no slop in any of the linkages and that everything moves together at the same time.

The best way to begin the balance is to remove the linkages off the balls of the throttle levers and have the engine running normally with the throttle arms resting on the idle speed screws.
Increase the revs a little so you are getting a decent flow through the barrels and use a length of thick heater hose to shove down the throat of the carb and put the other end to your ear. You will hear a popping note with a particular beat per minute and you’ll also hear a quite sucking, whooshing sound, take note of the noise and quickly swap the air-line to the other carb (no point testing the other barrel on the same carb as they should be identical assuming the throttle shaft isn’t twisted so jump straight to the other carb), your memory (assuming you are not a goldfish) should hold the previous note pretty well and you’ll notice the difference straight away once you have swapped carbs. Adjust the idle screw accordingly to increase or decrease the audible note trying our best to get them to sound the same (get used to adjusting one to match the other, rather than changing either of them at the same time). Flick the throttle every so often so you are sure the throttle valves are resting where they should be and haven’t rested on any hesitations upon the throttle shaft return.

When this is all done, dummy-fit your linkage by screwing or unscrewing the ball socket ends of the linkage arm to fit the ball on the throttle lever exactly (if you fit it and the main overhead throttle shaft moves then you need to reset the adjustment). After you have checked that they went on with no interference to the main throttle shaft secure them and make sure it’s all tight.
The next step is to do your road tests to see how they perform throughout the circuits, basically if there are jetting issues you’ll be able to determine which jets are requiring change by what stage the acceleration/driving is at. So I suppose this is where most the jetting happens.

Still got problems?

In the back of the manual that ddgonzal handed to you there are some trouble shooting issues that you can run through, in most instances the major problems are typically associated with these three issues:

1. Pilot screw settings.
2. Accelerator Pump Setting
3. Synchronisation.

The finer issues (flat spots, acceleration stutter etc) then become associated with jetting.

That manual is very useful and simple compared to the other manuals offered. It also goes into detail on how to set your pilot screws so you may want to have a look into that.

More manuals are available on Toyota forums that are specific to the engines that featured these carbs; 18r-g and maybe some 2t-g engines.

For spare parts;

RM Carburetors (AUS)

Sleeka (Celica) Spares (AUS)

Wolf Creek Racing (USA)

Do yourself a favor and use part numbers and proper part descriptions to save time and confusion.

thanks chris and after having ready through that post a few times i think i have a good idea of how to bacisly tune them and ill get a pic or ill find a good pic from my other thread and put that up

ok so i have found a pic on the RM carbys site (awsome site) and he carbys are 40PHH type S4 carbs and they are the earlyer PHH carbs ,but on the RM site it only says 44PHH type s4 but mine are 40s what could this mean ?

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