I just need to know whether or not it is a waste to buy injectors and a new fuel pump, with running only 3.25'' pulley.

 

no, but if i was you i would definitley start with new pump walbro Gss342

 

i don't think it would be a waste to get the injectors because like it or not your going to drop to a smaller pulley.

 

so freakin true, i remember my first s/c i said 6-7lbs is more than enough i'll be happy

 

I'd say the Walbro is required.

As for the injectors, what fuel pressure are you seeing at max boost?

 

I'm not sure what my fuel pressure is at any boost . Never been dyno'd or anything (assuming you can tell that from a dyno). Is the pump mentioned above 'Gss342' the right one for my year? Also, how long of an install is a fuel pump? I feel so lost all the time about this fuel man. stuff. When the pump is installed, is it still cool to use the same disc in my FMU?

 

The fuel pump is under the back seat. It should not take more than an hour. A couple screws and plugs. Just getting the pump in and out basically.

 

Thanks for the info. Now can someone verify that the pump specified above 'Gss342' is the correct one for an 01'?

 

i always thought that the 5th gen was harder to get out. yes gss342 should be the correct one.

 

I think that is correct and you want the HP model. Check latinmax's homepage for the HOW To

 

So would it be a good idea to start by installing the fuel pump, and then checking fuel pressure to see if I need injectors?

 

The fuel pump is a good idea, since the Walbro is sufficient for all fuel requirements. You don't need a booster pump. Any booster pump, relay or wiring fault under boost could lead to a lean condition and blowed-up motor.

The fuel pressure is not controlled by the Walbro, but by the FMU. My understanding is that the pressure will not change with addition of the Walbro, but your maximum potential pressure, supply volume and reliability will all go up.

The injectors are needed when a smaller pulley would require too much pressure or too high duty cycle for the stock injectors to be reliable. Larger injectors with a walbro and some upgraded fuel management can give you lowered pressures, duty cycles, better reliability and tunability.

I'd buy a walbro, fuel pressure gauge and cartech FMU; all from ebay. You can sell your Vortech FMU and t-rex pump to help offset what the Cartech / Begi will cost. Pop on the smaller pulley, and dyno tune with the Cartech. If the required pressures freak you out (over 100psi?) then you can look at larger injectors; but I'm told you can use your stock injectors down to 3.125". I bought injectors just 'cause I got a good deal, and I know that I will keep on going and going with more boost. I certainly don't need them right now.

Chris' Max is doing same stuff as well; all 5th gen. Let's keep in touch!

 

I already have the fuel pressure gauge ordered, and I'm ordering the Walbro tomorrow. What is a T-Rex pump? Also, what exactly is the Cartech FMU, and Begi, and is it a universal or MAxima specific part? Sorry if these are dumb questions.

 

Is this the cartech model that you're talking about... http://www.cartech.net/fmu2020.htm

 

the t-rex is what comes with the stillen kit. you foudn the begi/cartech yourself (theyre actually the same thing)

 

So where is a good place to buy a Cartech besides Ebay. The website listed above doesnt have a place to purchase(atleast that I could find).

 

Also, something else i wanted to ask, whats the difference between cartech and vortechs sfmu?

 

the vortech can adjust base fuel pressure (like an adjustable fpr)

the cartech does not contain any disks.

 

The main difference is that the cartech / begi FMU is adjustable with a twist of a screw; making tuning very easy. The Vortech requires you to dissassemble it and put in different disks for different rates. Making tuning hard(er).

Bought my Begi on ebay for $189. Sells for $259 at www.bellengineering.net Walbro was $90. I expect (hope) to sell combination of vortech FMU and pump for ~$150; so it's not too expensive when it's all done.

The bell engineering site has a better explanation, and tuning instructions.

 

are you talking about vortech regular fmu or sfmu cuze i heard sfmu is much easier and very flexible

 

Actually, the stock fuel pressure regulator is what controlls fuel pressure initially. The stock fuel pressure will go from 34psi at idle to around 40 psi at WOT via the stock fuel pressure regulator. Adding an FMU to the system allows you to raise that fuel pressure even more based on boost.

The fuel pressure will change when a the Walbro fuel pump is added. It bumps up idle and WOT fuel pressure by about 6-7 psi. But it does not increase fuel pressure base on boost after that like an FMU will.


IMO, If one already has the Vortech FMU I would just stick with that. Yes, the disks have to be changed instead of turning a screw like the Cartech but it is not a big deal to do. If any selling and buying were to happen I would get the Vortech Super FMU which is just like the Cartech with the screw and not the disks, but also allows base fuel pressure to be adjusted which is someting the Cartech can not do.

 

thats what I was asking above...Whats the diff between Vortechs SFMU and Cartechs?

 

I just told you.

Vortech regular FMU. Controls fuel pressure via boost using different size disks for different rising rates. The unit has to be opend and disks replaceds to change the rising rate. Base fuel pressure cannot be changed, and aftermarket fuel pressure regulator has to be used.

Cartech FMU. Controls fuel pressure rising rate via a screw on top of the unit. No disks to mess with. A aftermarket fuel pressure regulator has to be used to adjust base fuel pressure

Super Vortech FMU. Uses a screw on top of the unit for the rising rate just like the cartech, but can also adjust base fuel pressure. The best of both worlds.

 

Cartech/Begi also makes a super fmu with a base fuel pressure adjustment. I bought a JDM SARD FPR to replace the stock one, got a good deal and it looks cool. Ended up cheaper than paying the difference between regular and super Begi. Also has a handy fitting for fuel pressure gauge sender attachment. Now if only the instructions were in english....