1000Ccs Maxed Out At ~500Hp? E85 + Walbro 460

[TheGeniusMoose]

Hey guys,

Im stumped on a fuel issue in my R34 GTT,

It's hitting 100% duty cyle at 11.9 AFR up top at around the 500rwhp mark. Any help would be appreciated!

I've attached some screenshots of my map if it helps? Fuel pump has bigger wiring to it with a relay and direct battery connection.

Mod list below.

Standard RB25 NEO

Steam pipe high mount manifold

Garrett GTX3582R V-band rear housing

Turbosmart ProGate 50mm

Bosch 1000cc injectors

Proflow fuel rail

Tomei fuel pressure regulator

Plazmaman plenum

Haltech Platinum Pro ER34 Plug-in

Haltech 4 bar map sensor

Haltech boost control solenoid

Haltech flex fuel sensor

Splitfire coil packs

Custom stainless dump and front pipe

100 cell Venom cat converter

HKS HighPower 4" cat back exhaust

600x300x100mm FMIC

Tial 50mm BOV

Walbro 460lph E85 fuel pump

Edited October 8, 2014 by TheGeniusMoose

[Simon-S14]

whats your base pressure set to?

something isnt right, those injectors should not be anywhere near maxed out at 500rwhp

[Dose Pipe Sutututu]

how's your fuel pressure though?

I'm hitting 97% with 875cc injectors on E85 with about 1.6bar boost - however running 3bar base pressure. Newer injectors don't mind more fuel pressure, so once I need more "injector" I will bump the base pressure.

[Blackkers]

interesting. the Walbro pump should be able to handle more than that for sure. As well as the injectors.

How much boost was used before the injectors maxed out?

perhaps the fuel pump isn't genuine?

Do you have a direct feed for the pump?

I believe those ones can draw close to 20A at high boost. That's more than I'd be comfortable putting through the factory fuel lid connections.

Maybe drill a hole in the lid and poke some high current wires through then seal it up

[TheGeniusMoose]

Pump has direct battery feed with a relay, geniune pump. The lid has nice thick wires and does not get hot.

24psi boost.

Edited October 8, 2014 by TheGeniusMoose

[Simon-S14]

next question is, did the tuner tune to AFR or to Lambda? correct Lambda should be around the 0.81 mark... if your tuner tunes using afr his calculations could be way off in which case it's probably mega rich hence why its maxed

[TheGeniusMoose]

I'm honestly not sure.

The dyno chart shows that its at 11.9 at peak power. I didnt take a picture however.

I'm also using standard fuel pump cradle, standard lines under the bottom of the car.

Edited October 8, 2014 by TheGeniusMoose

[GTSBoy]

next question is, did the tuner tune to AFR or to Lambda? correct Lambda should be around the 0.81 mark... if your tuner tunes using afr his calculations could be way off in which case it's probably mega rich hence why its maxed

Any time anyone says an AFR number when talking about E85, and the AFR sounds like a petrol AFR, then just pretend the fuel is petrol. It's that simple. No-one would tune to a real AFR of 11.9 on E85.

[Kinkstaah]

What fuel filter are you using?

I'm not joking. I upgraded the injectors in your situation and had a limitation at that exact point.

Mind you, this is 372rwkw. It's getting 'up there' for 1000s.

If your AFR's start OK then start to leeeean out to about 12-13 as you really get into it.... seriously try something else instead of a Ryco filter. Try a dyno run without one.

[Simon-S14]

I run 850cc injectors, has made 423 rwkw on 22 psi, less then 80% duty. so close to maxing, so yeah 1000's should be able to do more no worries.

GTSboy: doesnt hurt to ask... some tuners do some strange shit...

[TheGeniusMoose]

Will try with no filter just too see what happens. It is running a cheap ryco one at the moment...

Who should I be taking it to so I can get this shit sorted? I'm in Brisbane.

[scotty nm35]

I have had a few 34's doing the same thing lately on ethanol, large injectors suddenly maxing as the fuel flow drops off. As Greg said, we removed his filter while it was on the dyno and the entire fuel map went rich.

His Ryco had only recently been changed too. We replaced it with a stainless mesh filter.

[Ben C34]

Why not put a pressure gauge on? Then you will see the pressure drop, if there is one.

[scotty nm35]

Exactly, that is how we found the flow was dropping off. You have no idea what is happening without a gauge on the feed line, and you need to be on a dyno if the gauge is in the engine bay.

Speaking of which, it seems some factory regs can be too small for the 460L pumps, they don't bypass enough. The S15 I worked on recently was tuned at 60psi at idle, no wonder the car wouldn't idle well with twice the fuel pressure it should have had. It is definitely an important test that should be checked after any major fuel system mods.

[TheGeniusMoose]

Yeah its got a genuine Tomei L type reg on it and the base pressure is set to 3 bar.

[iruvyouskyrine]

Exactly, that is how we found the flow was dropping off. You have no idea what is happening without a gauge on the feed line, and you need to be on a dyno if the gauge is in the engine bay.

Speaking of which, it seems some factory regs can be too small for the 460L pumps, they don't bypass enough. The S15 I worked on recently was tuned at 60psi at idle, no wonder the car wouldn't idle well with twice the fuel pressure it should have had. It is definitely an important test that should be checked after any major fuel system mods.

Fuel gauge on the feed line? Is a gauge on the reg not able to tell you correct fuel pressure?

[Ben C34]

Gauge on the reg is fine. Scotty would be referring to setups using stock regs.

Edited October 9, 2014 by Ben C34

[iruvyouskyrine]

Ah yep no worries.

[TheGeniusMoose]

Well I just bought a speedflow filter with barb fitting to replace current ryco one and a new bulkhead fitting for the cradle as a few people have said the stock fitting is very small. I'll have a fun weekend ahead of me!

Edited October 9, 2014 by TheGeniusMoose

[SiR_RB]

my walbro e85 pump is making 450rwkw at 24psi on e85 no problems so don't think its the pump

I think your injectors are at the limit, my old 1200cc injectors were at 100% duty at 409rwkw with 55psi base pressure