axial_pro

iTrader: (8)

Hey all,

I'll aim to keep this short & sweet: At a track day a couple of weeks back, I toasted a bearing that cut my day short.

I am running the APS TT kit from tip to toe including their fuel system.

The motor was tuned using Unichip when it was initially built many years ago. It made 469whp at 9.5lbs of boost on 94 octane - no wonder the stock block disintegrated!

I have ordered a Stage 2 long block from Kyle @ IPP and want to make sure that when it arrives I have the supporting parts to complete the build in a timely manner.

Given a goal of ~600whp, my questions are twofold:

1) What do I need for a fuel system? I understand that the basic APS gear will not be up to the task. People here seem quite fond of the CJM Stage 2 Fuel Return System. I gather that I need to couple this with some larger injectors and a higher capacity fuel pump. How do you determine optimum injector and fuel pump size?

2) Engine Management: Is the Haltech PnP clearly the best option or are there less expensive systems with enough capability?

Thanks in advance for sharing your knowledge and experience.

ttg35fort

iTrader: (2)

1) Yes, at 600 whp you will need a fuel return system.

By track days do you mean road coarse or 1/4 mile?

For 1/4 mile, the CJM fuel return system will be fine with the appropriate fuel pump and injectors.

For road course, if you will be on a long track, you also need to do something to make sure the fuel pump does not suck the factory swirl tank dry on long straights. (It happened to me at Sebring running a single 255 lph pump - car leaned out, sputtered, ran hot, etc.).

One way is to open up the hole in the bottom of the swirl tank. I have seen some guys also drill holes in the side of the swirl tank, near the bottom. Once you have drilled holes into the swirl tank, make sure you don't let your fuel tank get low when you are running the track. You need enough fuel in the fuel tank to keep the fuel in the swirl tank from pouring out through the holes you just drilled when you are going around a corner.

To avoid these issues, I run an external surge tank. It makes the fuel return system more complicated, and the fuel pumps sometimes get noisy. I have not yet tried it out on the track.

I have an Excel spreadsheet file that calculates fuel pressure, airflow, boost, etc., for desired whp. PM me your e-mail address and I will send it to you. It also has a bunch of other useful tools.

2) I would go with the Haltech Platinum Pro Plug-in (ECU replacement) for the 350Z if price were not an issue. Others have had success using Uprev Osiris to re-flash the factory ECU, and it is quite a bit less expensive than the Haltech ($700 for Osiris Tuner vs $2400 for the Haltech). You can search the tuning section of the forum and there is a lot of information there about the Osiris. I have heard some people who really like Osiris, and some that don't. I use it to tune my idle characteristics (with my old F-CON), but have never tried to tune drivability with it.

str8dum1

iTrader: (11)

For a built motor, Uprev is not appropriator choice. You no failsafes and it offers no more protection than the UniChip. In this day and age, i would personally never run without fuel pressure compensation, O2 lean faults, and full boost control all in 1 unit.

1 engine meltdown will easily cost multiples of a proper ECU. Haltech is the most straight forward for this platform and is worth the money.

For fuel, a walbro 400 in the stock basket with a return line. 1000cc injectors

ttg35fort

iTrader: (2)

Good points on the Haltech. Well worth the money.

Stock basket is fine for daily driving, 1/4 mile, autocross and short road courses. Not on long road courses, not without at least opening up the fuel inlet at the bottom. At 600 whp, the fuel pump will suck the fuel out faster than the small hole at the bottom will let fuel in, especially by the end of your run when your fuel level has dropped in the fuel tank. By your second run, if you have not topped off your tank, it get's worse. That is the issue I encountered with somewhere between 500 and 550 whp (I had my boost turned down to 12 or 14 psi at the time).

ttg35fort

iTrader: (2)

Remember, if you are pushing it hard in the twisties, by the time you get to the straight, you may not be starting with a full swirl tank (basket).

phunk2

the stage 2 system is adequate for over 600rwhp if you use the correct pump. i personally recommend the aeromotive stealth 11142 as it is a better fit for the factory pump module over the 400. but if you plan to use e85 rather than straight gasoline, than you might need the 400 to hit 600rwhp. the 340 pump pretty much made it to 600rwhp dynojet E85 in my 370z, but that is with 11:1 compression and only 52psi fuel pressure... higher boost levels and lower compression are going to need a stouter pump for 600 e85

for both the 340/400 it would be recommended to upgrade the wiring to the pump. the 340 pump i have seen get the connectors a tad melty over time. the 400 pump on stock wiring in my 370z makes the wiring really hot and i need to upgrade it before it blows a fuse or melts something.


wait it out a few weeks on the cjm kit if you choose that route. there is a new version of the rails that is much nicer coming out, no expected change in price. larger bore and fittings, integrated damper in 1-piece rail versus existing bolt on damper housing.

Eno

iTrader: (1)

On the surface Osiris looks like a cheaper option but when it comes time to getting it tuned, and finding people that are really good at tuning it... and all the supporting hardware required that is built into the Haltech- suddenly the costs start to level off. Upgraded MAF, boost controller, cable...

Haltech is still more expensive- but the availability of tuners, the nature of MAP v MAF tuning and the integration of a number of safety measures make the additional money more than worthwhile. (IMO)

thatv35guy

iTrader: (1)

I picked up this hard wire kit from DeatschWerks, in the process of installing it right now with the Walbro 400/E85 pump.

axial_pro

iTrader: (8)

That is all great advice and really helpful info, guys. Thanks.

I elected to go: Haltech Platinum, Injector Dynamics 1000cc, Walbro 400, and a CJM Stage 2 fuel return kit.

I definitely agree that the pump needs dedicated power for proper operation and safety from electrical problems.

One thing I do not understand is about a swirl tank. Never heard of it. Google here I come.

My track days are road courses ranging from flat and tight to fast and open. Mosport to Cayuga for the Ontario residents. Running 94 octane.

Exciting times! Hope everything goes smoothly.

ttg35fort

iTrader: (2)

Are you running an automatic or 6 speed? If you are running a 6 speed, you probably will be better off with the stand-alone Haltech:

http://www.haltech.com/product/plati...inum-pro-350z/

If you have an automatic, you are stuck with the piggy back. The stand-alone is manual transmission only.

axial_pro

iTrader: (8)

That unit you linked is what I bought.

6-spd of course!