Fuel Pump Any Gain?

[peter21]

for my standard r33 gts-t if i were to buy a fuel pump would there be any gain?

[TiTAN]

if the fuel pump isnt faulty. no you will not see any gain.

[joeyjoejoejuniorshabadoo]

in reliability... yes

in performance... no

[tridentt150v]

and assuming that all else is OK,,,,,,,regulator, filter, injectors, fp harness/wiring, turbo type, other fruit, etc etc.

So if your existing fuel pump is OK, then no gain, just reliability and ability to upgrade or lift your power output [more mods] and know that the fuel pump is able to cope: If your existing fuel pump is faulty and all the above are OK, then gain: If your existing fuel pump is faulty and any one of the above is faulty, then no gain. Its the 'weakest link in the chain' parable.

The amount of gain depends on how bad the old pump really was, if it wasn't going at all then 100% gain.

[lukebaldan]

Actually you may lose performance.

There's been a few cases where people have replaced faulty fuel pumps and lost power...The reason, the faulty pump maintained a lower fuel pressure hence leaning out the engine slightly.

[munz4130]

My short story:

Did a dyno on my stock rb25det S1....got only 180bhp atrw.....from the graph A/F was very very lean....damn dangerous & freaked out.

Suspected it was a faulty fuel pump, changed to walbro 255l (& FPR) then dynoed again with 0.8 boost got 255bhp atrw with very safe ie rich A/F ratio.

Hope that helps.

[Ultimategtr]

One of my friends put a Nismo FP in his R33 25t and since then it backfired alot and ran rich. He made 196rwkw @7psi boost. I think the dyno was rather happy tho.

He was also having issues with flatspots etc afterwards.

[mad082]

Actually you may lose performance.

There's been a few cases where people have replaced faulty fuel pumps and lost power...The reason, the faulty pump maintained a lower fuel pressure hence leaning out the engine slightly.

My short story:

Did a dyno on my stock rb25det S1....got only 180bhp atrw.....from the graph A/F was very very lean....damn dangerous & freaked out.

Suspected it was a faulty fuel pump, changed to walbro 255l (& FPR) then dynoed again with 0.8 boost got 255bhp atrw with very safe ie rich A/F ratio.

Hope that helps.

yeah it can work both ways. if the old pump is only slightly weak then on a stock ecu it can make your afr's good and you can gain power and then when you stick a new pump in you go back to being the typical stock ecu richness. however if your car is leaning right out then sometimes there isn't enough fuel to make a big enough bang to make good power so a new pump can improve power. this was also the case with my old s13. it gained 20hp from a new pump because the old one was stuffed.