What fuelpressure do you guys run? TPI

[Doktor-t]

Read on TPIS website that the reccomend 49-52 psi in fuelpressure on 88-90 year TPI wehicles. What kind of pressure do you run?


Tobias, SWEDEN

 

[bossvette]

Welcome to CAC I run 45 in my 76 at idle with the vacuum line removed

 

[Jeb]

The book says the L-98 should have a fuel pressure of between 40.5 and 47.0 PSI.

 

[Doktor-t]

fuelpressure

Thanks!


Do you think a fuelpressure of 53-55 psi is to high?

Has anyone got any issues with Accel adjustable fuelpressure regulator?


Tobias

 

[bossvette]

Just my opinion if you have to run fuel pressure of 53-55 its time to step up a notch with injectors. How are you taking your readings?

 

[Doktor-t]

fuel pressure

Just my opinion if you have to run fuel pressure of 53-55 its time to step up a notch with injectors. How are you taking your readings?

My engine is basicly stock and only with minor mods so far. The thing is that after I installed the ACCEL fuel pressure regulator (adjustable) the pressure increased alot. It is not possible to adjust the pressure below 53-55 psi (without vacuum) and that´s the main problem.

My engine haven´t the demand for such high pressure. I´d go with 50 psi if it was possible.

Damn accel crap.

Guess I have to assemble the plenum once again....

Hopefully I can get a refound or another better fuelpressure regulator from the speedshop I bought it at.


Tobias

 

[Vettefan87]

If it runs fine, and isn't running rich I wouldn't really worry about it to much, but I do think 53 is to high, that is if you are checking it with the vaccum line disconnected.
​

 

[ZumZum]

Holley makes a good AFPR

 

[Doktor-t]

fuelpressure

Well, it doesn´t seem to run rich but I haven´t got the chance to really testdrive it properly since there are ****loads of ice and snow on the roads. :cry

 

[Doktor-t]

FUELPRESSURE

Do you think the car will get bad milage (miles/gallon) due to too high fuelpressure?

 

[vetteboy86]

I am running between 52 and 55, but I have a modified engine. With the accel regulator you should be able to adjust the pressure below 50 psi. I really cannot believe there is a barrier at that pressure. I guess it could be faulty though. I bought a holly but the diaphram broke, and the customer service sucked. I think I bought a crane because it had a black housing. If it is running rich, and sure it will get worse mileage.

 

[Doktor-t]

fuelpressure

I am running between 52 and 55, but I have a modified engine. With the accel regulator you should be able to adjust the pressure below 50 psi. I really cannot believe there is a barrier at that pressure. I guess it could be faulty though. I bought a holly but the diaphram broke, and the customer service sucked. I think I bought a crane because it had a black housing. If it is running rich, and sure it will get worse mileage.

Vetteboy86, what modifications is done to your engine/car?


Regards

Tobias

 

[vetteboy86]

I just read your other post, that is a bummer about the fuel pressure regulator. I had a similiar issue with the holly I bought. The car started running like crap, so when I pulled the vacuum line off the regulator to check fuel pressure, fuel started coming out of the hose. I took it apart to find the diaphram broke. Apparently you cannot just buy the diaphram, so with the lack of cooperation from the people I bought it from, I went with another brand and so far so good.

 

[Louis Bartay]

I have a stock LT4 with some bolt on's air foil instock throtle body and I have a Breathless Adjustable Fuel Pressure Regulator and If I go above 50 PSI the OBDII throws on the check engine light. I have a Hyper-Tech Power Programmer, 160stat and a K&N open air box frame and filter and have moved the MAT sensor from the bellows in front of the throttle body to the air box so when it is 100 degrees out side the computer reads cooler air and does not retard the timing as much. My next mod is the under throttle body water kit as here in Texas it is not needed.

 

[Doktor-t]

fuel pressure

Today

 

[Doktor-t]

fuel pressure

Today when I drove home from work I stopped by at my parents house there I keep my Corvette.

After almost a week of annoying thoughts about the fuelpressure I just couldn´t get any rest before I checked the pressure once again.

I drove the car for a while utill it the engine reached operating temp. Hooked up the fuelpressure gauge and plugged the vacuumline.

Surpriceingly the fuelpressure wasn´t higher than 47 psi!? I couldn´t believe it but looked closly at the gauge and it was right.

I then raised the pressure up to 50 psi that is the pressure I wanted and according to TPIS it should be a good level.

I have to sa that it´s a big difference in throttle response with the higer fuel pressure.

After this I was really happy

Things are strange....