URGENT INFO! - For 20V Owner!

[EFN]

I will make this very simple!

If your 20Vs are running in these bodies before transplanting:
- Corolla SE.G EE100 1.3 Carbs
- Corolla SE EE90 1.3 Carbs
- Corolla LE AE82 Carbs
* Or any other body running carbs and below 1.6

PLEASE ENSURE THAT THE FUEL LINE/PIPE RUNNING FROM THE TANK TO THE FUEL RAIL IS NO LESS THAN 8mm in size!

I have checked a few 20Vs which are previously running 1.3 carbs and most of them are still using the 7mm fuel pipe which will cause the Fuel System to run HIGH PRESSURE PERMANENTLY! (10PSI Higher Than Normal). 20Vs with this setup will not be able to run the optimal 30-32PSI Idle Pressure, instead it will run within the region of 38-45PSI which is waaay too high for 20V NA. This will surely cost more fuel being burnt needlessly.

I am not telling this for my business benefit whatsoever, just helping fellow 20V owners.

* And yes, if your car have smaller diameter fuel pipe it will induce higher pressure but the actual volume might not be suitable at all.

So please check with your respective mechanics that done transplant for your 20Vs is they have upgraded the Fuel Pipe too.

 

[artnet]

alamak... once again... anyone got trustworthy mechanic in kuching....
edmund? terrence? any suggestion?

 

[sexycar]

but u cant get the original 20v fuel piping sizes.. they are
all chopped off... how can u get bigger diameter fuel piping
sizes & reroute all of them under the car body??

 

[EG9]

Ohhh...nowonder my fuel consumption is abit high.....
May change to cooper fuel line soon.......

 

[AE80TypeD]

what cannot get? no need to use the original pipe material oso can.. just browse thru ur regular hardware store and ask for the flexible copper pipings (tembaga). they usually keep them in coils around the shop. borrow the shopkeeper's vernier caliper or bring ur own and look for the required size. these are very easy to bend and shape and the are durable enuff for light mod use. just dont purposely bang ur undercarriage against a hump or potholes and it'll be alrite.

be warned tho, that these copper pipes are easily twisted becoz they are soft. they WILL hold up to the weather but not against ur hands/tools. they collapse easily if not handled correctly during bending. be delicate when working with them.

one aluminium shop here in puchong industrial area sells an aluminium/alloy version of piping, these are VERY hard and wont bend easily unless u got a vice or machine shop tools. unfortunately they sell them in long straight cuts of about 20ft each.

as for myself, i bought the cheap copper variant; a good 12 feet long for below RM20 with the external diameter of 10mm, internal cavity measuring roughly 8mm. i ended up using only 10feet from the tank till below the fuel filter; the small distance from tank to pipe and from pipe to filter is connected via hardware store 300PSI cloth braided hose.

never failed me even once for 3 years plus.. but i still set my fuel pressure to be around 38-40 at idle, even with the high volume line. how ah? hehehehe

man u guys should really read this page. its been around for ages. those who frequent acoustic's and bill sherwood's internet sites would surely have come across this matter. scroll down, have a look.

http://home.clear.net.nz/pages/phil.bradshaw/EFI Operation.htm

 

[TRDae92]

Really need a check!!!!

EFN, how about the car before installing is runnning the 1.6 ler???, the fuel hose piping is 8mm or 7mm???.......

artnet, kuching now still got trustworthy machanic lar,...... edmund now follow with me, no more hux SXXX liao... but since EFN tell the important for our 20v user, we should check it!!! take it serious.

Thanks EFN

 

[Acoustic]

east malaysia boyssssss don't say your side don't have good mechanic lah .............

You all say like that as if make the east malaysian adult forumers no face only, go visit the workshop more.....visit not only one but others ......... sure got one.....

Change copper fuel hoses so special meh.......... come on lah guys ...... don't sound like it's the end of the world.....

By the way it's the "RETURN" line which cuases increased fuel pressure.... but saying that, I'm using 7mm return, also no problem at all..... It's the original carburetor "INCOMING fuel line" which we convert to "RETURN"

While we add another new copper line, the cheap soft type like what Khairul said for the new "INCOMING". 8mm / 9mm I cannot remember...

No big deal...

On the 7mm return line, I can adjust my fuel pressure from as high as 60 psi to as low as 18 psi. I don't see why slightly small fuel hose making higher fuel pressure.. no offence to EFN.

The main thing controlling the fuel pressure is the regulator, so it may be a semi-faulty regulator. Going to die already regulator.

I've also seen fuel filters clog causing high low high low pressure.

I've also seen return stuck, bend rubber section, causing fuel pressure high....

I've also seen stuck fuel regulator.

It's normal things and excersice normal care / maintainese.



BTW, for a stock car the other thing which disturb fuel is the O2 sensor, you guys got healthy O2 sensor or not?? got install those cheap cheap AFR meter or not? even cheap meter will do. Must be the led swing high low high low... else the O2 sensor died.

 

[GT20v]

hahahah ive been telling this looong time already.......

high pressure doesnt mean got good flow and vice versa....its got to do with flow and velocity again..hehehe

10-11mm couple with a abit high pressure pump around 130lph is good up to 200bhp.......settle this our puny 120whp car got more than enuff fuel and to your surprise good fuel consumption also....

 

[TRDae92]

Thanks sifu Acoustic.......:)

 

[AE80TypeD]

yeap, i installed the big fuel line and used the old 7mm supply line as a return pipe. the old kuchi fart return pipe is now sitting there sucking air.

it is still a big deal favor from EFN to highlight this to the recent members, as it has been so long ago since our "generation" pasang the thing, we wouldnt even remember to remind them about it.

but anyways, this matter is extremely important if ur driving visits the 7-8k RPM very often. for normal driving (rare high revving), even with the stock regulator it should not be a problem, unless pipes or regulators are clogged as mentioned by acoustic.

 

[4agze]

EFN please help me to check this coming weekend ok?

 

[Acoustic]

don't thank me, thank EFN :)

 

[keithkeat]

EFN please help me to check this coming weekend ok?

4agze,call me too if u go....
wanna 8 8

 

[EFN]

OK OK I have left out a bit of info here. It is absolutely okay to maintain 7mm Fuel Return line because that is a low pressure passage and unused by the engine. Even all the 4G93T GSRs, 4G63T VR4s and EVOs that I have personally worked on uses 7mm Fuel Retun Line. Only cars like Mazda B8T, B6T and Nissan RB20DET & SR20DET uses 8mm retun line. But one thing in common is that they all use 8mm Main Pipe.

While for 20V's I will again stress that out of over 20 units that I have personally seen and worked on, no less than 5 of them have this problem of running high pressure permanently regardless what regulator they use. No matter what type of regulators placed and what springs used they still kenot go below 38PSI. After doing some hard research, I conclude that all these cars that have this problem are those which are previously running carb systems which uses 7mm Main Fuel Pipe, I did asked what type of fuel pump they use and they uses the very same fuel pump in my 20V. The only difference is that my Corolla was originally a 1.6 4A-FE and already use 8mm Fuel Pipe, and I don't have any problem whatsoever to reduce my pressure as low as 12PSI. Another main factor for running high pressure permanently is the pipe could have some unseen excessive bend - this can happen very easily due to mechanical clumsiness or road use.

Why I am making a big fuss about this? well it is up to you to judge wether this info is useful or not. I am just sharing for the benefit of all. If you think your car is already running perfect, by all means PLEASE IGNORE THIS MESSAGE.

Thank YOU

 

[Acoustic]

Hey EFN, when you say some cars have constant pressure, could it be due to vacuum leak??? i.e. the vacuum hose to the regulator is .... not good / whatever and causes atmospheric hence it's always in full mode???

May be the regulator itself is leaking, hence no vacuum, hence high pressure.

It's only a theory, I don't know.

 

[EFN]

Chin, if there is vacuum leak it is very easy to tell, The regulator would not fluctuate at all. what I am refering to constant high pressure is that even with very strong vacuum the idling pressure is still 38PSI and above and Full Throttle at around 46 to 48PSI.

 

[keithkeat]

EFN,u map look like near by my area,is it in between the setapak jaya and air panas?

lol

shop name,maybe find u today...ok?

 

[chinozie]

EFN...

thanx 4 the info...
BTW...

i) is my fuel line ok ???
ii) need to TT with u n ask u more details about this...hee interesting...

To all Sifoo...thanx for everthing

 

[sexycar]

hmm what bout 16v ? small carb fuel lines also can?

 

[EFN]

keithkeat:
Yup it's near Air Panas.

chinozie:
Woi kawan, your 20Vs fuel line cun-cun adi.

sexycar:
Actually this is applicable to any cars that have upgraded from 1.3 carb to anything above 1.6