Standard Fuel Pump On A Carb Conversion

[pugbender 0]

hi guys, i'd like to know the reasons why the standard fuel pump of a 1.6 gti can't be used with a carb conversion? perhaps the flow is higher than a facet fuel pump?how many liter for minutes(or gallons) does it has to pump?

[m.i-man 0]

It's the pressure that needs regulating. You need to drop the psi down to around 3-5....

 

You can either use your existing pump with a couple of adjustable fuel pressure regulators to drop the pressure. Or rip the old pump out, and fit a low pressure red top or something with an adjustable fuel pressure regulator also!

[pugbender 0]

thank you mi man so the solutions are:

- installing a fuel pressure regulator with 1 entrance and 2 exits before the entrance of the carbs with the std fuel pump;

- replace the old pump with a low pressure ones

but I was thinking..:the pressure of the std pump is due to the snd fuel pressure regulator so eliminating only the fuel pressure regulator the pressure will be less..so the rel problem is the flow:

how many litre for minutes has the std fuel pump compared to a facet pump ones?

[hodgy 0]

i un plugged the standard pump and fitted a facet silver top in the engine bay and lowerd the pressure to 2.5 psi with a filter king. if u leave the standard pump running it will jst fire fuel straight out the carbs and all over the engine like it did with mine!

 

i used a Facet silver top pump, filter king regulator

[hodgy 0]

a standard fuel pump is bout 70psi and the facet is 2-5 psi

[pdd144c 0]

You can either use your existing pump with a couple of adjustable fuel pressure regulators to drop the pressure.

 

And then it should catch on fire in no time at all!

[m.i-man 0]

And then it should catch on fire in no time at all!

 

I don't see how, as most of the fuel will be returned to the tank?

[ashley peddle 3]

And then it should catch on fire in no time at all!

 

only if you fit them poorly

[andy0075 9 1 Cars]

hi,

 

the original fuel pump of the XU9JA / XU9JAZ ( 1.9L 128PS/120PS ) pumps 130 liter per hour. That is the same as

the FACET SILVER TOP. The FACET RED TOP does 158 liter per hour.

 

If you would use the original pump with carbs, maybe you can take this. Found it on Ebay.

 

http://cgi.ebay.de/FUEL-PRESSURE-REGULATOR...oQQcmdZViewItem

Edited January 19, 2007 by andy0075

[ashley peddle 3]

If you would use the original pump with carbs, maybe you can take this. Found it on Ebay.

 

http://cgi.ebay.de/FUEL-PRESSURE-REGULATOR...oQQcmdZViewItem

 

that is a turbo regulator... will only take the pressure down to about 5... you then need an adjustable regulator to change it between 1 and 5... mine is currently set to 3.5

[andy0075 9 1 Cars]

Do you drive an 8V or 16V ? What carbs do you use 40's or 45's ?

 

I actually build up a 8V 205GTI with carbs, and i don't know

if it is worth to buy 45 carbs because of the much higher price

compared to the 40's. I have already an good flowed head, a middle hot

cam (280°, max lift 11,5mm) and a cr of 10,5:1.

Someone told me i should use a chokesize of 36mm with 45 carbs, but the

36mm chokes will also fit in the 40's . So, what is the advantage of the 45 carbs ?

[pugbender 0]

It's an 8v 1.6 with a 300° duration camshaft lift 11.5 (It's a french ones) ported head, home made intake manifold with 40's solex ddhe, 32mm chokes, 500gr off the flywheel and lightened front pulley.

[andy0075 9 1 Cars]

32mm chokes sounds very small ? but i have no experience in

practice, i just read a lot ;-)

I try the 36mm chokes when i bring the car back to life in one

or two month. But actually i dont know in what carb.

40mm or 45mm....grrrrr...

[pugbender 0]

probably 32mm chokes is too small but I'd like anyway to done a test, I imagine that a smaller chokes significe better low and middle throttle response, i read in the forum that a boy used a 40mm chokes in his 45's but when he put 36mm chokes he lost only 2bhp in top end power but he gained a better mid range response;

so 32mm on 40's probablt there arn't too small like they seems to be!

[mfield 20]

Someone told me i should use a chokesize of 36mm with 45 carbs, but the

36mm chokes will also fit in the 40's . So, what is the advantage of the 45 carbs ?

 

 

http://en.wikipedia.org/wiki/Venturi

[pugbender 0]

well, anybody have the electric circuit of a 205 1.6 gti I realy nedd it!I should do tomorrow a direct circuit to swith on the fuel pump!thk U