fuel upgrade question?

[bmeier]

Page 2 of this thread explains exactly what is wrong with a large fuel pump on a stock rail. I would spring 100 for a new rail if i were doing this personally. Also it shouldn't make the engine run any more rich if the FPR is working properly.

http://www.mr2oc.com/showthread.php?...bro+stock+rail



Wolfkatz has some good info here too
http://www.wolfkatz.com/articles.php


you can buy a bored rail from ats for $75 or one from wolfkatz

[thinmyster]

yeah i just hate sorting through the bs. i know i shouldnt have rode my car on my N/a fuel pump but i did. did i do damage?

[bmeier]

You would have known if you did damage, your engine would be toast...

[thinmyster]

so i guess its good (na pump) unless your boosting over stock. (from what ive read) APPARENTLY... thanks for the quick responses your my hero ben

[bmeier]

not necessarily, you could have run lean using the na pump. Just consider yourself lucky nothing went wrong.

[stealth]

Yea, I would of never risked it personally...

Have fun installing the pump

[jvillain]

Your right on the money bmeier. The issue is the preasure drop across the rail. Different combinations of pumps and rail result in different drops from side to side. The 2nd gen rail combined with an aftermarket pump being worse than the 3rd gen rail.

The resistor packs are designed to cut the amount of current that goes through the pump. The less current the slower the pump does it's thing and the less fuel it pumps. This does 2 things it can make the pump last longer and it allows the pump to run quieter at low rpms.

Unfortunatly the walboro is not engineered to run in the low current state. In that state it will not spin fast enough to cool it's self properly.

[stealth]

So even though I am on a stock rail and ECU, I should wire constant power to my walbro?

[thinmyster]

Straight from the wolfkatz site:

4) When should I replace my stock FPR?

If your stock fuel pump resistor pack is still in place, boost levels stay below 20psi, and you do not have a pump larger than the Supra Gen IV or Walbro 255, the stock FPR is fine.

Whats the stock fuel pump resistor pack and where is it? im NOT looking to remove it