Well, still sorting through issues with my recent rebuild. Car currently sitting at mid 400's with about 11 psi of boost. had fuel issues that kept us going higher. Working through those issues, tuner advises to install 10 micron inline fuel filters.

He recommends a set of fuel lab inline filters placed as close to the rails as possible. Problem is, each bank is fed by its own fuel line from the front of the engine. this leaves very little room for this type of filter. The short filters state they are 3" in length. there is definitely not 3" of space in that area.



My thinking is I have to pull the lines and cut each of them into two pieces. This would allow me to install the filters inline as they run along the firewall before tucking under the intake mainfolds. not the easiest install, but I think it might be the best. obviously before I go to this extreme would like to know if anyone has a better solution.



For reference

as you can see, the fuel lines are a single line running from the pump all the way to the rails. in the pic, they are the two long lines in the upper right with the red caps:




here is the front of the engine where the lines feed the rails. very little room for inline filter:





this is approximately the area I was thinking I would separate the feed lines and have new fittings install to accommodate the inline filters:

 

Isn't there a filter on the bottom of the fuel pump already?

 

There is, but not small enough micron to prevent potential debris making its way to clog an injector

 

Why place as close to the rail as possible? what is the advantage?

Most people place them under the car after y'ing the 2 feed lines together on the CJM kits.

 

thinking thats where mine will end up.

 

If the stock system works fine with it then I wouldn't see why this would be needed especially with an injector that has larger holes then stock.

 

the standard sock in fuel pumps is usually 100 microns, thats about .004 inchs for a fuel that is atomized to damn near a gas state when sprayed thats huge especially when you consider the holes in most injectors are .003-.004 inchs. even if the holes where twice the size it dosnt take long to clog, your average automotive fuel filter is 65 microns and after about 20k miles without changing it(an actual filter not the sock in the tank) they will get so clogged from pump fuels you can even blow through them. the after market ones can be cleaned out but i can tell you in professionally built systems you will usually have a 100 micron pre pump, with both a 65 and 10 micro post pump that get serviced every couple oil changes depending on use of the vehicle. the entire factory fuel system is actually complete ****. distance to the rails the only reasoning i could imagine would be long term to capture particles as the inside of the lines degrade.

 

The stock fuel system doesnt rely on the fuel pickup to be the "fuel filter". A 350z's actual fuel filter is molded inside the fuel pump housing.

 

can you elaborate on where this filter is? Is it serviceable?

 

no, it is not

 

it kinda is...if you buy a new fuel bucket for the low price of $200

http://www.ebay.com/itm/Fuel-Pump-As...NWtYI5&vxp=mtr

 

The white plastic fuel pump module that you insert the pump itself into, is the filter housing. This is why its important to add an external filter under the car when using twin pumps (CJM or the old APS), because these units do not have an integrated fuel filter in them (no room for it with 2 pumps anyway). IIRC, the Aps Extreme fuel system lacks any proper filter at all, depending on the fuel pump pickups as the only filtration. That sucks pretty bad. I would send the injectors out to be tested or replace them if its been run like this for a long time.

Stock filter is definitely not serviceable, as answered before me.

 

heres a little more detail about my situation.

Full rebuild over winter. Went for a tune on 5/21... at 11 psi, we are good... 12, 13, 14, maybe... 14+ no go. starting to detonate.

I get the car back and we think the issue is fuel related so first thing I do is pull the injectors. cylinder one injector has a glob of 'gunk' on it, so likely that is the issue. I send the injectors to RC for testing/service. here is the report:




note these are the APS "880" injectors as they test out at 3 bar vs the 4 bar APS rates them at.

Injectors had been cleaned and serviced prior to the 2014 driving season, so what you are seeing is after 2 season of driving... maybe 5k miles.

I had a pretty major injury that required surgery on my left arm that has me laid up till around labor day. I am in no position now to tackle this job now. For now, I am staying at 11 psi and when my arm heals up I will pull the lines, install some inline filters, have the injectors serviced again, and then go for a retune..... I've learned so much over the yrs with the car and sometimes the obvious, simple stuff still eludes me... the old saying, all the things I don't know could fill a warehouse....

going forward, the injectors will be tested/cleaned annually.