maximum Injectors for stock fuel pump

[GNONYX]

Can anyone tell me what the maximum fuel injectors size I can use for a stock fuel pump, and stock fuel regulator? Also can I keep the stock fuel pump and change over to a adjustable fuel pump to fuel feed the maximum fuel injectors? Thanks

 

[DailyDrifter]

Stock fuel pump . With all due respect, the fuel pump, filter, injectors, and regulator should be replaced with better units, and the fuel pump should be Hot Wired. After 24 years I dont think the stock unit is strong enough to hold up, the sock is probably clogged and collapsed. A new pump and hotwire kit is only about $160, add a adjustable regulator $109, 60lb injectors $330, and a turbotweak chip $85. Your looking at a total of around $700. Personally I would rather spend the extra money now and try to avoid a engine rebuild in the future. .02

 

[buickruss]

DailyDrifter nailed it

 

[GNONYX]

What I meant is all is replacement stock parts, and not that it's been original since 22 years ago. My 87 GN is T-Top with a Kenne Bell Rear Seat Brace (similar to the one Kirban Performance). I want to upgrade, but not for track racing, street run, and still keep the originally of the car

 

[DailyDrifter]

What I meant is all is replacement stock parts, and not that it's been original since 22 years ago. My 87 GN is T-Top with a Kenne Bell Rear Seat Brace (similar to the one Kirban Performance). I want to upgrade, but not for track racing, street run, and still keep the originally of the car

I still stand by my post. I would definatly upgrade the fuel system, and chip, weather racing it or not.

 

[rmar]

The stock pump was only rated like 28 gph.........

 

[DailyDrifter]

The stock pump was only rated like 28 gph.........

I think my stock Nissan flows more than that.

 

[rmar]

That's why with a hot wire and 009s at 80% Max.
No disrespect OP but your asking for trouble. Just with bigger injectors it will not run any better.

 

[GNONYX]

This is why I join and like the on-line TurboBuick Club, everyone has different of opinions on the same threads which not only give me and everyone else a different point of view.

 

[87GN_70GS]

According to the chart below:

http://www.turbobuick.com/forums/ge...h/280343-fulep-pump-injector-cheat-sheet.html

The stock pump will have trouble keeping up with stock injectors, at 100% duty cycle. The curves predict a max operating pressure of 60 psi, which if you start with 45 psi base, is 5 psi short of where it needs to be at a decent (20 psi) boost level. So bigger injectors will only worsen the problem. Answer is stock inj are the biggest for stock pump.

 

[DailyDrifter]

This is why I join and like the on-line TurboBuick Club, everyone has different of opinions on the same threads which not only give me and everyone else a different point of view.

This is the best site. Alot of people have great advice and we will try to point you in the right direction. Some members dont listen very well and end up with junk , just look at RMAR's sig.

 

[GNONYX]

I want to compliment on 87GN_70GS impressive fuel pump/injector cheat sheet, that was very informative. I didn't know how much is involve when trying to upgrade the fuel system, and of course the correct combination without blowing up the motor.
I do have a question, I installed a fuel pressure guage on the injector rail, and found that I was getting 32 psi. If the stock injectors are 28 lbs and fuel rail pressure has 32 psi, then what is the purpose of the fuel regulator? Am I missing something?
So let me understand something, unless I put a replacement injectors back on and run like the original factory, or start to replace the fuel pump, and hot wire since the original wire is aluminum and under size, replace the fuel regulator, bigger injectors, and finally ECM chip. Now I want to thanks on DailyDrifter combination on replacing the fuel system. Is there other injector combination I could use beside the 60lb injectors. I know alot you out there might not care of gas consumption, but I do like to drive around town and also country and want to maintain a good gas mileage with the upgrades. Please understand I am new to this fuel system replacement and I was amaze of the example 87GN_70GS gave with his chart.

 

[rmar]

Fuel System



Here is some reading......

 

[BlackOut89]

I also agree with dailydrifter, because let me tell you something when i got my turbo t it had 42lb injectors and the stock fuel pump and everytime you tried to get on it, it fell on its face due to the fact it was not getting the right amount of fuel it was calling for. So i bout a walbro 340 feul pump with hotwire kit from race tronics right away. Problems fixed....UPGRADE THAT PUMP MAN!!

 

[GNONYX]

I want to thank all for your great information, in my fuel system upgrade, specially for DailyDrifter in giving me his option of upgrading materials. now I have some work to do for this coming winter. I will post again on my out come of the upgrades. Thanks again

 

[DailyDrifter]

No problem, glad I could help. If you need anything let us know GBodyParts.com Online

 

[87GN_70GS]

The stock regulator is set at about 36 psi (with the hose off). So you are seeing stock pressures.

You can use any injector (as long as the appropriate fuel pump can keep up) you want. If the chip is matched to the injectors, your gas mileage should be the same. Bigger injectors should be controlled by the correct chip for them in much the same way as the stock setup as far as drivability and mpg's are concerned.