I dynoed my 95 5-speed Saturday along with some other Nismo types Saturday at Protech in Austin. I got 190 ft-lbs and 180 hp with CAI, y pipe and HKS exhaust. I normally run with a test-pipe and Stillen b pipe, but I had reinstalled the cat and stock b pipe in order to pass state inspection. Might have gotten an extra hp or two with the test and b pipe, but I'm pleased with what I got.

My fuel pressure has been running high at 50 psi since installing a Walbro fuel pump, and my AFR was measured at 12.8:1 Even so, the dyno operator thought I was running a little lean, in his opinion.

One of the Nismo guys that showed up to watch had an LT1 engine in his 240sx He didn't dyno, but he said he runs high 12's in the quarter mile.

 

i don't get it... the 4th gen claims 190HP stock @ crank, howcome u only got 180HP??

 

190 is the factory rating at the crank.

Dynos measure the power that actually makes it to the wheels (always less).

 

Hmmm, maybe it's because I don't have any stickers... Just kidding.

The stock 190 hp is measured at the crank. I got 180 hp at the wheels, so if you divide by .85 to take into account drive train losses (is that the right number for a 5-speed?) I got almost 212 hp at the crank.

 

In your case, where you are modded, your numbers are about right... I have a similar setup with my car, dyno'd 181.6hp at the wheels and 194.0tq. at the crank...when I dyno'd stock, I came up with 156hp at the wheels and 170-something tq. at the crank....

although I'll have to look into a fuel pump for my car, that may be interesting...

 

heh I have to redyno my car...I found out the APS actually lowered my HP

 

156HP?? daymn tat sux =X

 

What does the upgraded fuel pump do? I mean, I understand what a fuel pump is, but does this help you performance wise? being NA?
Thanks and good #'s by the way,
Dan

 

I have a supercharger sitting in my garage. I have been doing the prep work for the blower installation, and the Walbro fuel pump was part of the prep work. I opted for the Walbro instead of running the Vortech aux fuel pump.

 

it does nothing unless you have a dying oem fuel pump.

 

It does run high pressure instead of the oem.

 

Does this give worse gas mileage? How much more horsepower will you get with an upgraded fuel pump if you are NA? How much do they cost?
Thanks,
Dan

 

An upgrade fuel pump will not result in a HP increase on a NA vehicle.

D

 

It won't increase HP on ANY vehicle.

All a fuel pump does is.... pump fuel! If your car doesn't have the ability to utilize and burn that extra fuel it can pump (which no N/A VQ does) you will see no difference.

 

Wow, is this ever wrong. If your current fuel pump can't flow enough fuel on your forced induction car (N/A won't need more fuel than the pump can deliver), you will definitely feel the lack of top end power as your fuel lines depressurize. Larger injectors help deliver that extra fuel too.

But as everyone else says, if you don't have an S/C or Turbo, a fuel pump won't make any difference.

 

how is that wrong? he said the exact same thing as you. unless you are boosting, a n/a car would have no need for a higher fuel pump.

 

No, it wasn't wrong. Fuel pumps don't gain you HP. They are a way of getting more fuel to the engine.

That said, you may NEED the fuel pump to get extra fuel to the cylinders assuming you are flowing enough air to utilize it, but a high flow fuel pump doesn't gain you power on its own without a significant increase in the amount of air being taken into the cylinders.