What is the maximum fuel pressure I can run before my stock injectors will start to freeze in the closed position?

The reason I ask is because with my new setup, I can make my 19 lb injectors work at 68 PSI, and holding an 85% duty cycle at WOT. I know the TBI injectors don't go static until about 90 PSI, but they are a much larger injector. Also, what is the maximum fuel pressure the stock TPI pump is capable of reliably putting out without dying?

If the injectors can support that kind of pressure, what will the effects on the spray pattern be?

On the other hand, I can run 24 pound injectors and run 48 psi at 80% duty cycle, and get the same amount of fuel.

Here's the site where I'm getting all the info from. FruityOne gave me the link for it You need to register, but there are alot of cool things to play with.

I can do the first choice for exactly $0.00 assuming the pump can support the pressure needed and the injectors dont lock up. The second choice will run me roughly $150-200 for a set of new 24# injectors.

Mods are in the sig...

 

I found a good deal on some LS1 28 lb/hr injectors, so I got those. I can run those at les than 80% duty and still get the fuel I'll need.

 

i personally wouldn't run too much fp. reason being, thats how i blew my motor. i gas washed my rings.

do you wanna take the chance of that happening to you? i've had 2 of my friends tell me that happened to them in their iroc-z's, so i know it just wasn't me.

keep your fuel injectors and set it at 45-46 psi and leave it at that. if you go to 24# injectors, you should lower the fuel pressure down a little, as well as re-buring the prom for those injectors.

btw, you don't need new injectors for the mods you have... atleast not till they start to die on ya. and if they do, i'd only go with 24#'s on a 305 if you've got a lot of mods. take a look at my mods on my page, and im only running 24# svo's at 40 psi (for now... when i take it to the track, ill do some fine tuning)

 

19 pound injectors will only efficiently support up to 270 hp at the crank at 80% duty cycle, and stock fuel pressure. That is about the maximum duty cycle without quickly killing them.

Running these new injectors, I won't have to mess with fuel pressure at all. Like I said, for the mods and predicted power I will have, I would have to run about 65 PSI and 85% duty cycle to get the 19 lb injectors to work. If I had the L98 22 lb/hr injectors like you had stock, then I might feel comfortable just bumping the pressure. I could potentially run 40 lb injectors on the 305 with a proper burn. All I would have to do is narrow up the PW.

Oh, here's the link to the site I was talking about above. I forgot to post the link.

http://www.smokemup.com/auto_math/fuel_injector2.php

Alot of fuel pressure will not kill the motor, as long as you control the flow (by adjusting injector pulse width) As long as the engine can use the fuel it is recieving, and it doesn't flood the chambers. Many gas engines are up to about 80 PSI, and I read an article not to long ago stating that many of the diesel motors are running in excess of 3000 psi.

Thanks for the input DJ. Have you had the car to the track since you got the new motor?

 

nope... the engine's finished, it just needs to be dropped in and broken in properly the moment it's ready, it's headed to the track. i dunno what to expect... my mechanic says high 12's, my prom tuner told me high 12's, i built it to hit high 12's, so thats what im hoping for. could have used better parts, but my pockets are pretty much empty at this point of my life, lol. let me stop here before i ruin your post, lol