Rising rate fuel regs

[Pupp]

One for the turbo/SC guys really - what RR fuel reg are you using (and any pointers)?

[SILICONEKID343HP]

Pupp said:

One for the turbo/SC guys really - what RR fuel reg are you using (and any pointers)?

I thought the ECU does the fuel enrichment ! The old flapper runs at 14.7 all the time so relies on the rising rate regulator for enrichment ..

[phazed]

True, rising rate for 14 CUX but not required for MS, emerald etc.

[fatboychim]

I'm using a BEGI, seems to have sorted the initial leaning out problems I had soon after the SC install.

http://www.bellengineering.net/product_info.php?cP...

[Pupp]

Thanks for the BEGi link; very helpful. Anymore for any more...?

[SILICONEKID343HP]

phazed said:

True, rising rate for 14 CUX but not required for MS, emerald etc.

The fuel regulator for the 14cux is a standard 2.5 bar regulator not rising rate ,the 14cux ecu as it`s own fuel enrichment.

[blitzracing]

More to the point, if the fuel pressure rises or falls faster than the stock regulator and the ECU is in closed loop, the ECU than has to correct it back to lambda 1, so the fuel control becomes very ragged has you get a battle between regulator and ECU.

[spend]

blitzracing said:

More to the point, if the fuel pressure rises or falls faster than the stock regulator and the ECU is in closed loop, the ECU than has to correct it back to lambda 1, so the fuel control becomes very ragged has you get a battle between regulator and ECU.

It always is the case....

Irrespective of the 'expected / set pressure delta' the fuel delivered depends on flow as inj opens + time open * flow + flow as inj closes ~ noting that just like when you turn lots of taps on the pressure in the supply will change with demand & where you are in the supply chain. There are lots of differences in expected supply to pots that get mixed up the more you batch / bank the delivery, not least differences in time the fuel is hanging around in the port prior to being 'blown' which affects the mixing?

Closed loop does not really have the capability to understand all these variations so you can only consider it as a pretty gross system unless you are able to run closed loop on a cylinder x cylinder basis?

[carsy]

Pupp, what injectors are you going with. If big enough cant you fit a normal 3 bar reg. Apparently there is a bmw 3 bar one which is a direct fit.

[spitfire4v8]

I've just mapped a supercharged chimaera with that BEGI regulator on.. it took some real faffing around to get it to give the desired increase with boost .. as std even with the bleed fully open it was adding 30lbs extra pressure for just 3 psi boost! (fuel pressure initially went from 40psi to 70 psi before the car had even gone over 2500rpm!) To get it to work properly you have to really restrict the boost pressure fed entry pipe hole .. I managed to find an old weber carburettor jet that fitted into the entry pipe which restricted the inlet enough to allow the bypass to function properly. It most certainly is not a fit and adjust part as supplied. It's a nice enough piece of kit, but there's got to be something better on the market ..

[Pupp]

Thanks guys - still not settled on particular injectors so suggestions welcome! On the reg, and as Jools hints, Im thinking a BEGi or similar as well as (not instead of) the OEM reg *should* counteract boost peak lean-outs rather than have any effect in 'normal' driving - guess the deal gets tougher if boost peaks become the norm

[v8 racing]

Hi Pupp your running emerald aren't you?, forget all these fancy fuel regs and just control the fuel via ecu, providing you have a decent selected set of injectors for the given power there is no problem, I have to say and I know you probably wouldn't but jacking the pressure up to try and get it right is just wrong!

[Alexdaredevils]

Here is what im using on my set up,

http://www.ebay.co.uk/itm/Torques-AN-8-ORB-8-EFI-A...

[v8 racing]

Whats wrong with the standard reg, just curious

[Pupp]

Yes Rob, it's a K3 Emerald so has MAP and boost correction capability - all for keeping it simple if that's possible!

Thanks for the link Alex

[spitfire4v8]

The std regulator can't hold the pressure differential across the injector as boost increases .. with the 10psi of boost that the chim was making at the top end the nominal 40psi I'd set the pressure to with no vacuum would equate to a real 30psi at 10psi boost unless the fuel line pressure is increased to compensate. Some form of rising pressure regulator is required, but not a rising rate one, just a 1:1 regulator that senses boost is all that's required. I set the BEGI rising rate regulator to give 10psi extra line pressure on 10psi of boost. job jobbed. ps Rob did you get my email about cams the other day ?