So I'm starting to upgrade the fuel system and wanted to know what to watch out for, and some other questions. I'm prepping the system for future modification, that will hopefully be done next year. Here is what the powerplant will look like when completed:

VG30 block bored to 92mm
VG30 heads ported and polished
VH33 pistons & rings (because of turbo)
VG30 crank with VG30 UDP and oil pump
VG30DETT rods
?? valves
custom ground cams
VG30 intake manifolds ported and polished
Z31 exhaust manifolds ported and polished
turbocharger system

Would it be better to go with VH45 pistons, keeping the turbo in mind? I'm thinking the lower compression of the VG33 pistons will be better for turbo.
What valves should I use...stock VG?
Any other upgrades such as springs, etc?

OKAY....so on to my questions!!

Taking alll those future plans into account, how should I go about upgrading the fuel system?

I'm thinking I should start with a Walbro pump, but which one? There are three..the HPLV, LPHV, and HPHV.

Do I need to modify the ECU to handle to fuel pump? Will it run rich since I'm putting on a larger flow pump? Should I upgrade the fuel pressure regulator to an adjustable one?

Then I'll upgrade the injectors....but I have no idea what injectors to use.

Either way, I'll eventually have to modify my ECU to handle the injectors, and want to get a custom program. When is the best time to do this? At the same time I'm putting in the injectors? Before? After?

Is there anything else needed to upgrade, such as the fuel rail?

I haven't really done any serious performance mods like this, so it's new territory for me. The transmission swap and stuff like that is pretty easy, IMO it's more like a bolt on mod. The fuel system and anything controlled by the ECU is an entirely different beast.

Any helpful responses or links regarding the 3rd gen's fuel system are appreciated. Thanks!!

 

did you mean vh45de pistons?

 

i think that as long as your FPR works, it should hold the pressure correctly to run good AFR. Only so much fuel can push through the injector in 1ms at 45psi... regardless of pump. Now if you get higher-flow injectors, that may be a different story, because they will let through more fuel at the same PSI.

but don't quote me on this b/c i've never had to deal directly with something like this.

 

Yes...yes I do. But the VH45 pistons have a higher CR than the VG33...which isn't as good for turbo, right?

 

Its easy ... to spread 'bolt on' the highway. That will happen -IF- you get real serious power to be delivered onto wheels.

A tranny is like flexing balloon, std bow is calculated to take the 200hp. Rigidity for box case, bearing sizes, also engine/tranny support attachment need to be strengthened to take the planned beat.

 

Im not sure on what kind of injectors it will take for the Vg33 but for my Vg30 turbo I put a set of 370cc from 300zx along with walbro 255lph adjustable regulator and tunning with SAFCII. It will run rich on initial startup but that is easily adjusted by the SAFCII. I installed all of them together when I put the turbo on and of course a A/F gauge to get a street tune till get some dyno time. Here is a video on the SAFCII gives you a good Idea how it tricks the ECU.
http://youtube.com/watch?v=PRH7hnHI6QM

 

well I think I'd just be using the VG33 pistons and rings. The VG33 block has more material for boring out, but if I just bore it a little smaller I'll still be fine with the higher pressures.

Thanks for the info akurtzer!

@wiking.....I'll cryo treat the gears before embarking on the turbo path. As a side note, what are the main parts I should strengthen since cryo treatment is $$$$.

 

the AFC should only allow a certain amount of adjustment, if the injectors are letting out too much fuel and you go -20 to correct it may work but if your at -50 and they are still to rich than you have problems needed to be solved by ecu! if you plan on going turbo you can keep the stock injectors get urself a nice 4:1 FMU and as the pressure build so will the fuel delivery! If you plan on running more than 14psi I would say go for the bigger injectors and try to tune them, but with a turbo it spools differently every time depending on when the open throttle is done? so Its safer with an FMU, the Fuel Managment Unit increases based apon its ratio disc in this case I suggest 4:1 thus 4psi increase in fuel for every 1psi increase in manifold pressure! It works so well with my turbo setup that I bearly need to adjust on my AFC neo to get a perfect a/f but can still adjust accordingly! Use a walbro 255lph and 4:1 fmu with ur AFC and you should have a perfect a/f till you go turbo and when its turbo it will increase the fuel pressure and work well together! PM me if u have any questions!

 

I have no real powerplay experience. However, one note: most stock trannys come with lots of 'spare' attachment holes. On some cases these may be used to add extra supports... no scientific method - but one std nissan tranny main axle seal stopped leaking after using extra support (case flexing must have been stopped).

 

That's pretty interesting! So the FMU replaces the regulator? You're saying that instead of running JUST an AFC, it would be better to run it with the fuel managment unit? And the FMU can be used with and without the turbo?

What FMU do you reccomend? Vortech? Cartech?

@Wiking....where are these extra support holes you speak of?

 

I need to have the details of your bbk. Thanks

 

The best turbo fuel system would be the Tuned ECU route.. Thats what i run. You can you use nearly any Nissan rom editing software. Ive used Live edit(Free) in the past and currently use nistune(Not free).

As for the engine, Why not just put the time and money into The turbo setup and boost the stock engine, they are absolutely bulletproof. If this is your first major build then i would recommend not adding more variables than necessary. Once you get it Running well and get to the limits of the stock engine, then build it. However you will be past the limits of the trans before you'll be past the limits of the stock engine.

 

maxmaxima91 raises some really good points. I would focus on the turbo set up and not worry about cryo with the tranny. I had mine done and still broke 3rd gear. Throw some redline in there and called a day (unless you got the bucks for PAR gears)
As for the fuel set up, figure out your power HP goals first. I initially kept the fuel system simple and changed it once I worked out the kinks in the turbo system. I ran a FMU, Walbro hp, stock injectors, and AFC for almost three yrs before I increased my power level from around 300 to 400whp. Never had any issues with that fuel system.
good luck

 

What details do you seek? It's slotted/drilled rotors from 97 Mustang Cobra, 30mm Z32 aluminum calipers, SS lines, your adapters and rings, slotted/drilled rotors from a Z31, 90 maxima rear caliper brackets, and there you go.

@4signs - I'll end up with 400 fwhp, but would like to see numbers similar to yours initially. It's good to know that I can just upgrade the pump and put a FMU and AFC on it and have 300hp with the turbo. Did you also go with a 4:1 FMU? I already run redline trans fluid...LOVE IT!

Thanks everyone for the AWESOME help so far! Here's my plan after all this conversating....

1) Walbro pump
2) FMU
3) AFC
4) turbocharger and ROM edit
5) build another engine on the side
6) build trans accordingly

sounds about right? I can run the Walbro HP Pump with FMU and AFC with the stock ECU right? Man I love acronyms.

Anyone have exactly which Walbro pump I should be looking at?

 

the sooner you rom edit the better, FMUs kinda freak me out. but hey... they can work fine i guess... all i can say is... WIDEBAND...

 

Another thing I meant to mention if you were to bore out your VG30 to VG33 yes there is enough material but then boost it your block will be alot weaker. Better of getting a VG33 block. Also saves on machine work. But it is look at maxmaxima91 12.8@14psi or joeboost built VG30 384hp and 412tq. Not sure specs on turbo or psi but have seen some z31 guys with stock bottom ends pushing 430hp with few bolt ons and a gt35(awsome turbo on my list). Just bang for the buck get low mileage VG30E build headers and run around 10psi on good sized turbo for the motor and you will be happy.

 

I love the gt35r

 

I'm aware of the extra material on the VG33, but I also know it takes some more modification. If I can get away with big HP numbers without boring out the block, I will. It would be nice to do though... I probably won't build custom headers, I'd just use Z31 headers. They are said to flow very well. Ending up with a ride that gives me numbers like Joeboost would be great. But, as of right now I'm mainly concerned with the fuel system.

This entire summer is going to be dedicated to finishing the R34 tail lights, kit, soundsystem, alarm, and paint job. Also I'm going starting to aquire parts for the fuel system, which is why I started this thread. I've already got a Walbro pump lined up, and just need to find the injectors, a good FMU, wideband O2, and AFC. The GT35 is also my turbo of choice.

edit) Recently my fuel gauge only goes 75% up (even with a full tank), will stay there untill I use 25% of the fuel, and then go down like normal. What would be making the needle stop at 75% full? Bad sender? Bad gauge?

 

power on a turbo motor is largely a matter of how far you want to push it. the difference is that a bored-out motor will have quicker response before boost is present, then you can run a little bit less boost to hit the same power figures. but if you are shooting for 275WHP (i forgot what your actual goal was) then you can get it on the 33 or the 30, it's just a matter of how you want to get there. it's one of those things where, no matter how much you hate hearing this phrase, "it just depends".

 

sender is probably bad.

 

I'd like a solid 3-400hp that will be used as my DD.

Brian, can I purchase the sender from you? Where is a good place to source one of these? I'd rather avoid the dealership.

 

sadly it is dealer/JY only

 

Traxtar, any update on this? I was looking for upgraded fuel injector info and came upon this thread. I am interested because I have pretty much the exact same goals as you. How far along are ya? What did do with the fuel set up? Any progress w/ the R34 taillights and/or turbo prep? Let us know.

Thanks,
Mrkanda

 

Ditched the R34 plan... they're currently for sale if anyone's interested. Turbo prep is in planning stages. I'm finishing up the head lights as we speak and I'm trying to figure out why my pre-wired fog lights don't get power when I use the switch I got at the JY. I thought all you need was a switch and foglights, and everything should work....

Anyways... I installed the HP Wahlbro pump and I'm running a bit rich, but the install went well. I don't notice any difference, but then again... I shouldn't. It's a very straightforward install.

 

if your car is in good running order (new tuneup, good compression, good injectors, etc) the 02 should handle richness in most cases unless you just have too much fuel pressure and it's already running the leanest maps it knows how to run.... so either some sensor (CTS, 02) is wacked, or your fuel pressure is too high i'd think. but i've never messed with the fuel system before so there may be more to it.