Hi Guys,

I have just finished my build and I'm currently breaking the motor in on the standard APS fuel system. In a few weeks I want to fit the new fuel system and shoot for the upper limits of the APS turbos on pump gas. Hopefully around 550rwhp on a Dynapack.

Im trying to make a decision on the fuel system. On one hand I don't want to go overboard and waste $$$ but I also don't like the idea of being on the "edge" of the max fuel supply.

So far I have narrowed it down to a few options:

1. CJM Stage 2 Return with single Warboro and DeatschWerks 800cc injectors
2. APS Extreme fuel system.
3. AAM Stage 1 return with Stage II pump and DeatschWerks 800cc injectors

I can see pro's and cons to the different systems. Some people have said that I should just leave the standard APS system in place and upgrade the injectors as I'm using the Haltech. I can't see the Walboro supplying enough fuel pushing against 4 Bar base pressure. Also at what point do the standard fuel rails become a limitation flow wise?

The car is mostly street driven but will soon be used in some weekend trackdays. What do you guys recommend? My engine specs are below:

Standard Block overbored 20 thou and honed with a Torque plate.
Standard Crank - Magnafluxed and polished etc
Eagle H Beam rods
Wiseco 8.8:1 forged pistons with ceramic coating
ACL Race bearings
ARP Main Studs
Revup Oil pump
New Waterpump, Timing chains and tensioners.
Standard Heads with minor porting
Standard Valves with new race seats and some unshrouding work
BC Stage 2 cams
BC Valvesprings and retainers
ARP L19 head studs
HKS HeadGaskets
Standard APS Spec Garrett Ball bearing turbos
Forge Actuators (Blue Springs)
APS 3.5" Test pipes
APS Tallboy Plenum
Haltech Platinum ECU
Injected Performace Rear Coolant mod

Thanks
Matt

 

I have CJM rails with return system and Twin in tank pumps it is great quality and i have been very happy with it. I also run HKS 1000cc injectors you might want to consider larger injectors so you have room to grow in the future. My system might be over kill for your goals but CJM is quality parts IMO. I personally would want a return when going for 550whp but I think people have done it on stock rails with the JWT mod(see there web site for details) and some people also cut the OEM rails and weld AN fittings on them to make a home made return system if thats your thing.

 

+1 for the CJM. Stage 1 here - good to 550-600 whp is my understanding, then twin pumps needed...

 

on what Gord and Raj already told you.

 

I just looked at CJMs web site it looks like you would be maxing the stage 1 system at 550whp the stage II is supposed to be good for over 650whp. Stage II still uses a 255lph pump it seems it changes the lines to larger lines for less pressure and more flow.

 

I think the most you will be getting out of the APS TT kit is in the 600+ WHP range so you should be good with the CJM Stage 2 Fuel system then you can add the Twin fuel pump later on just for that extra assurance.

 

If you are running the standard aps semi return fuel system with 800cc injectors, it will work for 500-550 hp range. It has a 1:1 rising rate regulator. Try this set up first. Then if you or your tuner are not happy with it then change it out. I'm running this exact fuel set up with no problems.

 

i've got the hardline used in the stage 2 just sitting around, i'd be willing to sell.

 

^ Why didn't you install it? I may be interested, not that I need it exactly, but then I didn't really need twin turbos.

 

We are not exactly clear on where the Stage 1 ends... it has seen plenty of 500-550rwhp cars. but beyond that, we arent sure. it might be able to make it to 600rwhp. we rate our systems in "dynojet" hp since that is the type of dyno we used to own.

 

i used it for <2 years, but some additional mods under the car had the bend where it connects to the soft line to the FPR bumping up against something ceramic coated that couldnt be moved out of the way. damn low hangers.... Had to reroute a custom -8 thru the frame rail and up along the engine wall.

 

I have the APS extreme system and I would get the CJM if I did it over again. The APS system is decent, but at around 1/3 tank and less, I see pressure dips. This has me filling up all the time as I don't like to let it get below 1/2 tank

Also, discuss your fuel system choice with your builder and tuner and see what they recommend

 

what about using an external surge tank??

 

a post i made on another forum about external surge cans;

the external swirl pot is nice and all, but I really dont like the idea of a pot of gasoline being in the interior of my car in the event of a collision. especially when there is a pump constantly pumping into that pot... and if the pot were to rupture.. hopefully someone is conscious to shut off the in-tank pump that is pumping gasoline into the interior. I look at it sorta like trying to put a mechanical fuel pressure gauge in interior... just cant say that im a fan of pressurized fuel lines feeding the cabin. maybe in a race car with an added rear fire-wall, but not a street car on the track. IMHO anyways.

 

^^^ never really thought about that the 800hp Z i saw one on was a roadster soo that does make a little bit of a difference...

 

why would it be inside the car? you would mount it on the rear subframe just like the AAM surge

 

Twin pump w/ CJM stg 2 return and the DW 800s.

You probably aren't going to see more than probably 650whp max with those normal APS twins and those BC Stg2 cams, so no need to go for bigger injectors imho, you could go larger but I see no need to until/unless you get away from the little APS standard twins, but you will be getting really close to maxing out a single Walbro at your planned 550whp (it's Walbro btw, not Walboro, sorry, that's just a pet peeve of mine).

 

He will run out of steam at high 500's, and might touch 600 if things go well.

 

Do you mean the fuel pump (single) will run out of steam, or the APS turbos?

 

turbos