[Built4thrashing]

Some differences i have found when pulling them apart is the sierra has 2 jets in the fuel bowl but the corolla only has one. The corolla has less Vac lines and doesnt need any water lines attached to it for the choke. Also the internal vac and fuel circuits seem to be slightly larger and less prone to blocking up .


B4T

[Built4thrashing]

And the primary throat is alot bigger. Secondary is about the same.


B4T

[rick1970]

Primary is a little bigger and secondary is a little smaller than the Sierra carb. Still has both jets in the fuel bowl.

[atari4x4]

found this US thread about the corolla carby.

http://www.acksfaq.com/toycarbinstall.htm

[russty_2008]

do the corolla carbys like angles

[2stroker]

russty_2008 wrote:

do the corolla carbys like angles

Yes they do, yanks reckon they are better on angles than a standard carbie.

People have trouble with Webers and Holleys flooding on angles and the car stalling. The yank forums reckon that for offroad the recomendation is lower the float level, fit the replacement nylon needle and seat instead of the factory brass one, run a fuel pressure regulator and fit a offroad vent kit which vents flooded fuel to charcoal canister instead of back into the carbie.

[mat428]

I just fitted a corolla carb. Had a bit of trouble with it, but its getting better.
just wondering where all the vac lines go and what ones to block off.

[ryan]

i have just put a 4k carb on mine and i think i have worked all the vacuum lines out.
On the engine side of the carb the line closest to you is for the carbon canister, the next one which is a bit higher is the vac advance for the distributor, then the other two on that side you don't need.
on the front of the carb there is one vacuum line for the hot idle thing and on the side facing out from the engine there is a line for the secondary throat.
and any thing else can be blocked off.

[roughzook]

gay! i just chucked out 3 or 4 4k carbs the other month.

[JrZook]

2stroker wrote:

People have trouble with Webers and Holleys flooding on angles and the car stalling. The yank forums reckon that for offroad the recomendation is lower the float level, fit the replacement nylon needle and seat instead of the factory brass one, run a fuel pressure regulator and fit a offroad vent kit which vents flooded fuel to charcoal canister instead of back into the carbie.

This make them better but the fundamental flaw is the position of the fuel bowl and the effect that gravity has on it going up steep up/down hills. The vent kit stops the bowl breather from spilling into the throats but does nothing for the fuel from the bowl being gravity fed through the mains, up the emulsion tube and into teh throats. If you could mount the carb sideways they would nearly be on par wit the stock one offroad i believe

[buddah_04]

Fitted a corolla carby today, put a kit through it. had to make a accel cable bracket, but that was easy enough. the sierra secondary is a little bigger, so a little less power with the corolla carby, but idles well, runs well, starts alot easier than the suzuki one, seems to be able to handle big angle hills.

im not sure if the one i have is a 4k, might be a 3k or somthing, mine has 2 jets in the bowl, the one in the bottom for secondary and the one on the side for the primary.


im going out next weekend, so will be a good test for it.

[Moph]

How did you hook up the fuel line, buddah? It seems the thread on the carby is M12 and I can't seem to find a barbed fuel line fitting to match

[buddah_04]

Moph wrote:

How did you hook up the fuel line, buddah? It seems the thread on the carby is M12 and I can't seem to find a barbed fuel line fitting to match

the M12 adaptor comes off the carby, then where it comes off, is the same size as the sierra, so just bolt the sierra one onto it

[Moph]

buddah_04 wrote:

Moph wrote:

How did you hook up the fuel line, buddah? It seems the thread on the carby is M12 and I can't seem to find a barbed fuel line fitting to match

the M12 adaptor comes off the carby, then where it comes off, is the same size as the sierra, so just bolt the sierra one onto it

Thanks ... I had one of these moments.

They happen way too often when I'm tinkering with cars

[HarryHoudini]

Old thread,but does anyone tell me which vacum line(if any) of Corolla Carb. goes to Charcoal Canister ??also are the wires off the hot-idle(?) connected to anything. TIA.

[HarryHoudini]

Bump,..anyone have a photo of where vacum lines go and where the wire for hot idle is connected TIA

[Santos]

Thread Necromancy!!!!

=====
Just sold a 4k carb this week that i decided not to use. I am including a modded intake in the sale. I test fitted everything so that it would be as haslefree as possible. Whilst i had skimmed ackfaq a few times only when i was getting the bits and pieces to post did i really read through it thoroughly.

http://acksfaq.com/toycarbinstall.htm

Also there is a 3 part youtube video on the installation
PART 1

-===-

Something people seem to neglect to mention every time i read about the 4k carb is the 4 bolts you need to attach it to a suzuki sierra intake. whilst you can get away with some shorter (m8?) bolts for the two for the throttle lever side you REALLY need two studs and nuts on the fuel bowl side. In fact 4 studs would be better. so if you are pulling the carb from an actual toyota get the studs at the same time. I got two studs from a junked sierra head. Strangely they were slightly different lengths (1mm or so) but its important to put the shortest one on the cylinder head side.


As you can see in the above photo the smallest bolt with some thread left doesn't fit.

=====

I don't agree with Acks setting up the fuel float bowl to the rear, this should only be done at tuning stage then flipped to the front like a sierra carb. That way when climbing slopes under load the fuel sits over the jet orifices. Much better to have fuel available going up cause gravity always help you going downhill. Angles can be deceptive and very rarely do people ever do 45 degrees for more than a few metres. Also i feel that it matters where the primary and secondaries are in regard to suzukis intake design when driving under load.

If you agree and do it this way don't forget that the 'thermal spacer' or 'throttle body spacer' mentioned in Ack faq and in the 5k video need to be modded differently.

His drawing is inaccurate (or may be its just how the american Hitachi carbs are set up ) as the smaller hole sits inside the half moon vacuum groove that says 'FILL IN THIS AREA' so the holes are reversed. So you are supposed to cut a vacuum groove on the primary side according to his faq and the 3K you tube video. In which case you just need to cut a groove from the smaller hole into the half moon groove and mount it upside down to get the exact same effect, no need to fill the half moon and cut from top.


I flipped the plate for two reasons.
One: the need for filling in the halfmoon and makes knowing where to cut the groove easy. Yes it has to be on the that side if you are running the carb in the stock configuration of fuel bowl to front. so if you dont flip it you need to cut the groove into the small triangle as shown in ack faq and you need it to do it from the top so it goes into the carb

Two: It makes sealing the plate to the intake with engine sealant easier as its all flat. Top should always be a gasket so you can tune the idle then flip it right way. (bottom permanently mounted saves forgetting to mount the plate or losing it! )

I marked the throttle body/thermal spacer in green so you could see its a bit hard to distinguish with the extra black engine sealant. The yellow bits are parts of mods to intake and would be empty internal space on a stock intake.


Lastly the You tube video talks about how he had difficulty getting the right stud for the stock carby-hat. I found a suitable bolt in my bits box. Basically it comes from the timing pulley set up on suzuki g motors. I'm pretty sure any asian motor would have a similar thing on the timing pulley. I put two nuts as spacers and it lined up nicely. The stock sierra one does not fit. MAKE SURE YOU USE A STUD FOR THIS! Don't use a long bolt as the carb is aluminium, eventually the hard steel bolt will chew through the thread after taking it on and off s many times.


-====-
DISCLAIMER: I haven't installed a 4K myself. All of the above is based on all my experience with the sierra carb and carefully studying the 4K carb in person and seeing how they would hybridize.

[Santos]

Well typing that up, making photos, fixing broken links, re-doing it cause i timed out on server etc was soooo painful i hope it helps somebody.

[andrew]

yeah im having troubles with this project car i bought
im fairly sure its carbs ive cleaned it out but to no avail
im considering bolting on a 4k rolla carbie if it just bolts on easy to get my hands on