Max power on stock fueling?

[dthebuk]

Hi guys, quick qu

Just wondered what kind of the power the stock fuelling system will support? Can be with any other mods etc


cheers

[turbo boy]

About 375bhp

[SiH]

Totally stock? as in stock pressure?
I made just over 340bhp, I wouldn\'t want to push it much further than that. Injectors were hitting 94% peak.

Knock the pressure up and you can add a bit, but the pump will struggle. hardwire it and it will do better.

[dthebuk]

Sweet. That\'s all I needed!!

Im guessing stock Ports, intercooler, exhaust, air filter and more boost will get you there?

[SiH]

I ran downpipe, decat, cat back, Apexi filters, XS power IC (in a V, but that\'s sorta irrelevant), and power FC, and it made 343 extrapolated horses - can\'t remember the real (atw) figures.

That was, however, mapped by Pip at WGT, who is apparently \'crap\' and maps \'pig rich\', :rolleyes:
The car felt fantastic, couldn\'t fault it.
Then I fitted a Walbro, 1680\'s, and an Aeromotive reg, and had it mapped again by Pip, and it had a shedload more midrange, and felt punchier at the top end, as well as peaking 20bhp higher.

[RXSpeedy]

What kind of bait are you using Sih? ragworm is good this time of year lol.

On topic:

I wouldnt want to be venturing near max peak just incase. Id just get 850\'s instead of the 550\'s and run them all round just to be safe.

[brodierx7]

I ran downpipe, decat, cat back, Apexi filters, XS power IC (in a V, but that\'s sorta irrelevant), and power FC, and it made 343 extrapolated horses - can\'t remember the real (atw) figures.
 
That was, however, mapped by Pip at WGT, who is apparently \'crap\' and maps \'pig rich\', :rolleyes:
The car felt fantastic, couldn\'t fault it.
Then I fitted a Walbro, 1680\'s, and an Aeromotive reg, and had it mapped again by Pip, and it had a shedload more midrange, and felt punchier at the top end, as well as peaking 20bhp higher.

 
I got mine mapped by pip with basically the same mods except i havent fitted my downpipe yet, also had the fuel pump hard wired. i got mine mapped and fitted a power fc but only made 292bhp? i was a bit disappointed but in order to get more i take it i need to get the boost up?

[carl0s]

I make 400hp with the stock fuel pump & lines. Can\'t comment on injectors etc.

[Wombat-007]

I ran 355fwhp with stock downpipe, de-cat and racing beat back box, apexi pfc and boost controller and blitz air filters and street port.
With Stock fuel and ignition, the boost had to be dropped due to 100% injector duty. Running 340fwhp safely.
Running stock fuel, get it mapped by an RX7 specialist that will recomend reliability not max power/boost. REWORX could have left mine at 355, but did the sensible thing and lowered the boost to keep it safe.

[turbotoaster]

i maxed my stock injectors(100%) out at 360bhp at the fly on stock fuel pressure with hardwired stock pump
changed to 850cc primarys and maxed them out at 20psi of boost on stock twins, will decrease the duty with my 2x044s im bolting in i would have thought, especially if i increase the fuel pressure if i can be bothered with a fpr

[bimbleuk]

My car was dyno\'d at 415 BHP & 400 lbs ft but it isn\'t rotary powered. I would say the dyno is a bit over optmistic as the engine according to Holden (hint) outputs 380BHP so probably more like that. The fuel pressure regulator is standard for the engine but fairly high at 58 PSI. The pump is wired separately to get max voltage constantly.

[m1tch]

i maxed my stock injectors(100%) out at 360bhp at the fly on stock fuel pressure with hardwired stock pump
changed to 850cc primarys and maxed them out at 20psi of boost on stock twins, will decrease the duty with my 2x044s im bolting in i would have thought, especially if i increase the fuel pressure if i can be bothered with a fpr

Injectors max out at about 90% duty cycle, going further will cause them to vibrate and only 1/2 the fuel will be injected and the engine will run lean.

Safe max on injectors is about 85%, I wouldn\'t push stock fueling on a rotary that far, its ok a bit more, but they aren\'t exactly new injectors, im waiting to uprate my secondaries before upping the boost on mine, its not worth the risk, few hundred pounds on fueling upgrades vs £3k engine rebuild if it detonates? No brainer for me really :2Rolleyes

[SiH]

Injectors max out at about 90% duty cycle, going further will cause them to vibrate and only 1/2 the fuel will be injected

:Hammer
What? Where did you get that from?!

85% is accepted as the \'safe\' limit by many people, and many, including myself, lean towards an upgrade when past that. However, the rest of your post appears to be absolute garbage.
Care to quote any references?

[Prof]

You may find this site useful:
 
http://docinjector.com/info1.htm
 
Basically I think what Mitch was reffering to is that an injector has finite turn on and off times, and if you \'overdrive\' it, it\'s possible the injector is not operating in a linear region and therefore it\'s flow isn\'t guaranteed or mappable.  The ECU should be programmed with the lag (sometimes called battery) time which is the time it takes the injector to reach full flow, and during this time the injector flows a proportion of full flow rate, the cut off is normally much quicker, as the spring snaps the pin back in the injector body - but again some flow rate will exist in this portion.  If these turn on/off events occur so close to gether the injector might actually only be giving half flow for most of the time it is \'on\' - not really what you want...
 
Stick to keeping injectors below 85% duty and there\'s no headaches

[SiH]

Oh yeah, I\'m not denying that driving them above a certain duty induces an element of risk and upredictability, but \'vibrating\' and only injecting \'half\' the fuel?
The prose I\'ve quoted implies that venturing above 90% duty halves the amouny of fuel injected - All evidence I\'ve seen debunks that. It may yield diminishing results when winding up the duty too far, but reducing it by that amount?

An awful lot of peole run injectors way beyond the 85% (or 90%, or 80%...) \'guideline\' that many people quote with no ill effects at all, on thousands of different set ups all over the world. Belt and braces suggests you don\'t, but it doesn\'t mean it doesn\'t work for a lot of people.

It also depends what\'s being measured in terms of duty as well - for instance, 100% \'duty\' on an AVCR isn\'t actually 100% injector duty - it\'s something else related to it that I\'m far too stupid to understand.

The internet is full of chinese whispers tuning advice, and I think sometimes people need to be wary of perpetuating this. Says a man who\'s just stated an internet \'fact\' in his post.