TBI Fuel pressure testing and installing gauge

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I live in area that I would need to order the exact parts needed to
check the fuel pressure. I understand you adjust the pressure at the
TBI itself. but do you cut the fuel line and install a gauge and at the
same time install a secondary fuel filter.


Re: TBI Fuel pressure testing and installing gauge
 
TBI Fuel pressure testing and installing gauge  
 
Group: alt.autos.4x4.chevy-trucks Date: Mon, May 30, 2005, 5:57pm
(CDT-2) From: snipped-for-privacy@yahoo.ca
I live in area that I would need to order the exact parts needed to
check the fuel pressure. I understand you adjust the pressure at the TBI
itself. but do you cut the fuel line and install a gauge and at the same
time install a secondary fuel filter.


ok well  what year make and model is you car/truck?
And for a TBI the fuel pressure is regulated by the fuel pressure
regulater.Not the throttle body itself..And by NO means cut any
lines....Why would you need a secondary fuel filter?
What exactly are you trying to do?
S Cook


Re: TBI Fuel pressure testing and installing gauge


Steve Cook wrote:
Quoted text here. Click to load it

Sorry 1990 chevy PU 5.7, so where is the fuel pressure regulator
located, my goal is to test the fuel pressure, from my understanding it
should be between 9 to 13 PSI, I think the ideal pressure is 10.5 PSI.
lower pressure gives lean mixture and to high pressure will give you a
rich mixute. So does it make sense to check this pressure and how do
you adjust it. As far as a secondary filter, with my marine experience
I have always run a secondary see though filter.


Re: TBI Fuel pressure testing and installing gauge
 
Re: TBI Fuel pressure testing and installing gauge  
 
Group: alt.autos.4x4.chevy-trucks Date: Mon, May 30, 2005, 7:13pm
(CDT-2) From: snipped-for-privacy@yahoo.ca
Steve Cook wrote:
TBI Fuel pressure testing and installing gauge
Group: alt.autos.4x4.chevy-trucks Date: Mon, May 30, 2005, 5:57pm
(CDT-2) From: snipped-for-privacy@yahoo.ca
I live in area that I would need to order the exact parts needed to
check the fuel pressure. I understand you adjust the pressure at the TBI
itself. but do you cut the fuel line and install a gauge and at the same
time install a secondary fuel filter.
ok well what year make and model is you car/truck? And for a TBI the
fuel pressure is regulated by the fuel pressure regulater.Not the
throttle body itself..And by NO means cut any lines....Why would you
need a secondary fuel filter? What exactly are you trying to do?
S Cook
Sorry 1990 chevy PU 5.7, so where is the fuel pressure regulator
located, my goal is to test the fuel pressure, from my understanding it
should be between 9 to 13 PSI, I think the ideal pressure is 10.5 PSI.
lower pressure gives lean mixture and to high pressure will give you a
rich mixute. So does it make sense to check this pressure and how do you
adjust it. As far as a secondary filter, with my marine experience I
have always run a secondary see though filter

Ok the fuel pressure regulator is more than likely under your upper
intake.
The fuel pressure should be between for this engine 42-55 PSI
Your right about the lower and raising of the pressure but you cannot
adjust if but you can advance and retard the timing...You will eighter
Have  a service port or you will need to disconnect your fuel filter and
use a adaptor which you can connect a pressure gauge too...A Second
filter wont help you much if your trying to keep out  water...But there
is really no need for a second filter...Why is it your worried about
your fuel pressure?
S Cook


Re: TBI Fuel pressure testing and installing gauge
Steve, I believe the TBI on this truck is 10-15 psi and the regulator is in
the TB itself. If I remember correctly it is under a small cover plate, it
is the spring loaded diaphragm type.
Quoted text here. Click to load it



-

Re: TBI Fuel pressure testing and installing gauge
bingo. Finally the RIGHT info.


Re: TBI Fuel pressure testing and installing gauge
wrote:

Quoted text here. Click to load it



that right. The regulator is part of the TBI "unit", and as you say
the pressure should be around 13lbs.  I just went through the
fuel pump swap and the mechanic tested the fuel pressure.

They have an adapater that allows a manual fuel pressure guage to be
connected to the fuel line that feeds the rear of the injector. I
think you connect this near the fuel filter?


---
Elbert Clarke
elbert.clarke@**adelphia.net
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Re: TBI Fuel pressure testing and installing gauge


Elbert wrote:
Quoted text here. Click to load it

Thanks I think I am getting closer to answer,but where i am starting to
loose it,the fuel pump pressure seems easy to read, just but a pressure
gauge near the fuel filter. That way you don't have to break the fuel
line. Now that is going to show you fuel pump pressure. So the next
thing is to take the cover off at the far end of the TBI and adjust the
pressure into the TBI to 13 to 15 PSI. So my next question is where do
you get that reading from. I some how don't think it would be the gauge
that you install at the fuel filter or am I missing something. Where I
live you can not just drop into your local chevy dealership and ask
them to check TBI presure.


Re: TBI Fuel pressure testing and installing gauge
 
Re: TBI Fuel pressure testing and installing gauge  
 
Group: alt.autos.4x4.chevy-trucks Date: Tue, May 31, 2005, 6:16pm
(CDT-2) From: snipped-for-privacy@yahoo.ca
Elbert wrote:
Steve, I believe the TBI on this truck is 10-15 psi and the regulator is
in the TB itself. If I remember correctly it is under a small cover
plate, it is the spring loaded diaphragm type.
Re: TBI Fuel pressure testing and installing gauge
Group: alt.autos.4x4.chevy-trucks Date: Mon, May 30, 2005, 7:13pm
(CDT-2) From: snipped-for-privacy@yahoo.ca
Steve Cook wrote:
TBI Fuel pressure testing and installing gauge Group:
alt.autos.4x4.chevy-trucks Date: Mon, May 30, 2005, 5:57pm (CDT-2) From:
snipped-for-privacy@yahoo.ca
I live in area that I would need to order the exact parts needed to
check the fuel pressure. I understand you adjust the pressure at the TBI
itself. but do you cut the fuel line and install a gauge and at the same
time install a secondary fuel filter.
ok well what year make and model is you car/truck? And for a TBI the
fuel pressure is regulated by the fuel pressure regulater.Not the
throttle body itself..And by NO means cut any lines....Why would you
need a secondary fuel filter? What exactly are you trying to do? S Cook
Sorry 1990 chevy PU 5.7, so where is the fuel pressure regulator
located, my goal is to test the fuel pressure, from my understanding it
should be between 9 to 13 PSI, I think the ideal pressure is 10.5 PSI.
lower pressure gives lean mixture and to high pressure will give you a
rich mixute. So does it make sense to check this pressure and how do you
adjust it. As far as a secondary filter, with my marine experience I
have always run a secondary see though filter
Ok the fuel pressure regulator is more than likely under your upper
intake.
The fuel pressure should be between for this engine 42-55 PSI Your right
about the lower and raising of the pressure but you cannot adjust if but
you can advance and retard the timing...You will eighter Have a service
port or you will need to disconnect your fuel filter and use a adaptor
which you can connect a pressure gauge too...A Second filter wont help
you much if your trying to keep out water...But there is really no need
for a second filter...Why is it your worried about your fuel pressure?
S Cook
-
that right. The regulator is part of the TBI "unit", and as you say the
pressure should be around 13lbs. I just went through the fuel pump swap
and the mechanic tested the fuel pressure.
They have an adapater that allows a manual fuel pressure guage to be
connected to the fuel line that feeds the rear of the injector. I think
you connect this near the fuel filter?
---
Elbert Clarke
elbert.clarke@**adelphia.net
remove ** to email
Thanks I think I am getting closer to answer,but where i am starting to
loose it,the fuel pump pressure seems easy to read, just but a pressure
gauge near the fuel filter. That way you don't have to break the fuel
line. Now that is going to show you fuel pump pressure. So the next
thing is to take the cover off at the far end of the TBI and adjust the
pressure into the TBI to 13 to 15 PSI. So my next question is where do
you get that reading from. I some how don't think it would be the gauge
that you install at the fuel filter or am I missing something. Where I
live you can not just drop into your local chevy dealership and ask them
to check TBI presure.


Sorry for the wrong info....Guess its before my time...But Even I
learned something today...
Thanks for the correction..
S Cook.


Re: TBI Fuel pressure testing and installing gauge


Steve Cook wrote:
Quoted text here. Click to load it

I live in Cabo san Lucas MX and the dealer is confused with changing a
tire, so I think I have a lot better idea on where to go with. I am
running the complete edelbrock Power package. I still think there is
some more HP with combination. I am hearing everthing from 10.5 PSI to
13PSI. My understanding is that the higher the PSI with-in reason, the
richer the mixture.
Quoted text here. Click to load it


Re: TBI Fuel pressure testing and installing gauge
On 31 May 2005 18:16:09 -0700, snipped-for-privacy@yahoo.ca wrote:

Quoted text here. Click to load it






As far as I know there is only one pressure to check and thats the
"fuel" line pressure, which is generated by the fuel pump and
controlled by the regulator. If you are talking about this on a 5.7
TBI 1990 pickup then thats what we are talking about.

Any GM dealer should have the appropriate fuel guage and adapter
to check this. I don't know if you live in the US or in another
country.

I'm not aware of any other way to check the fuel pressure on a 5.7 TBI
truck in this year model range. These engines don't have a port like
some of the tuned port engines, that makes it really easy to do. If
you want to check the fuel pressure you are going to have to get
in-line with the fuel system.

I'm not aware of any way to check the fuel pressure behind the
regulator as I think you are saying above. I don't know if the
regulators are even adjustable?

Elbert

---
Elbert Clarke
elbert.clarke@**adelphia.net
We've slightly trimmed the long signature. Click to see the full one.
Re: TBI Fuel pressure testing and installing gauge
Regulators are not adjustable, unless they have a stronger spring available
to increase the pressure. If it is computer controlled the richer mixture
would be corrected  to some extent by the o2 sensor, so that may not in
itself make a difference, a performance chip may be the only way to
accomplish this.
Quoted text here. Click to load it



-

Re: TBI Fuel pressure testing and installing gauge
Shep wrote:

Quoted text here. Click to load it

Yes and no, the regulators don't come from the factor adjustable.  There are
a few ways around this, remove the FPR assembly and you will notice the
adjusting screw on the bottom has a restrictor that can be removed to give
you access to the screw.  Or you can waste $50 and buy an adjustable billet
aluminum assembly.  The easiest way around this problem is to drop in a 1/8"
thick lug nut spacer washer between the spring and body.  The washer will
boost the pressure up 1.5 PSI.

This is a much needed mod if you use a performance chip and a 165*
thermostat.  The extra pressure isn't a problem and the TBI will be fed what
is needed under normal "closed loop" conditions.  It's when you hit WOT and
you are in "open loop" is where you see and feel the benefits of the extra
pressure, just get more air in and you'll be fine.



Rita




Re: TBI Fuel pressure testing and installing gauge


Rita =C4 Berkowitz wrote:
Quoted text here. Click to load it

Thanks for all your input, has anyone had any hands on experience with
this companys products.   http://www.cfm-tech.com/TBI_Performance.htm


Re: TBI Fuel pressure testing and installing gauge


Rita =C4 Berkowitz wrote:
Quoted text here. Click to load it

Thanks for all your input, has anyone had any hands on experience with
this companys products.   http://www.cfm-tech.com/TBI_Performance.htm


Re: Re: TBI Fuel pressure testing and installing gauge
"Shep2" wrote:
 > Steve, I believe the TBI on this truck is 10-15 psi and the
 > regulator is in
 > the TB itself. If I remember correctly it is under a small
 > cover plate, it
 > is the spring loaded diaphragm type.
 > >
 > > Re: TBI Fuel pressure testing and installing gauge
 > >
 > > Group: alt.autos.4x4.chevy-trucks Date: Mon, May 30, 2005,
 > 7:13pm
 > > (CDT-2) From: snipped-for-privacy@yahoo.ca
 > > Steve Cook wrote:
 > > TBI Fuel pressure testing and installing gauge
 > > Group: alt.autos.4x4.chevy-trucks Date: Mon, May 30, 2005,
 > 5:57pm
 > > (CDT-2) From: snipped-for-privacy@yahoo.ca
 > > I live in area that I would need to order the exact parts
 > needed to
 > > check the fuel pressure. I understand you adjust the
 > pressure at the TBI
 > > itself. but do you cut the fuel line and install a gauge and
 > at the same
 > > time install a secondary fuel filter.
 > > ok well what year make and model is you car/truck? And for a
 > TBI the
 > > fuel pressure is regulated by the fuel pressure
 > regulater.Not the
 > > throttle body itself..And by NO means cut any lines....Why
 > would you
 > > need a secondary fuel filter? What exactly are you trying to
 > do?
 > > S Cook
 > > Sorry 1990 chevy PU 5.7, so where is the fuel pressure
 > regulator
 > > located, my goal is to test the fuel pressure, from my
 > understanding it
 > > should be between 9 to 13 PSI, I think the ideal pressure is
 > 10.5 PSI.
 > > lower pressure gives lean mixture and to high pressure will
 > give you a
 > > rich mixute. So does it make sense to check this pressure
 > and how do you
 > > adjust it. As far as a secondary filter, with my marine
 > experience I
 > > have always run a secondary see though filter
 > >
 > > Ok the fuel pressure regulator is more than likely under
 > your upper
 > > intake.
 > > The fuel pressure should be between for this engine 42-55
 > PSI
 > > Your right about the lower and raising of the pressure but
 > you cannot
 > > adjust if but you can advance and retard the timing...You
 > will eighter
 > > Have  a service port or you will need to disconnect your
 > fuel filter and
 > > use a adaptor which you can connect a pressure gauge too...A
 > Second
 > > filter wont help you much if your trying to keep out
 > water...But there
 > > is really no need for a second filter...Why is it your
 > worried about
 > > your fuel pressure?
 > > S Cook
 > >
 >
 >
 >
 > -

TBI trucks run at much lower pressure. It should be about 11 to 15 PSI
from tank and around 9 to 10 PSI on injectors after regulator.

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