max boost pressure on stock?

Prof · May 23, 2011, 03:24:09 PM

Quote from: yiug412;764334My car idles very rich as well at 11 without SAFC. with SAFC it\'s still hard to get up to 14.
I have a question:
I have converted the secondary to 880cc and i thot it would be running very rich. surprisingly with stock actuator and no boost controller, it boost all the way up to 0.9 bar with around the 12s. is it something wrong with my engine?
and yes good HT leads and spark plug makes a difference on AFR when boosting

Secondaries are only ever running above 3500rpm and on boost, never any other time, so the primaries are doing the bulk of the work. Without knowing your setup, it\'s my guess the fuel pressure isn\'t there at the top end cancelling out the larger injector benefit - but like I say, it\'s conjecture...

It\'s why I went down the emanage route - as you can log so much stuff before during and after making mods - so you can actually see what\'s happening. And a fuel pressure gauge is a worthwhile investment too - for dyno testing.

AFR\'s on idle - low to mid 13\'s are fine - that\'s about stock anyway. Only ever see the 14\'s on cruise between 1500 and 3000 rpm when the narrow band lambda actually does something

, It\'s not used for idle (like on other cars) and not used for top end fuel correction either - that\'s all MAF and latterly MAP based with tables.

I\'ve managed to tune my idle AFR\'s to about 14 when warm, but it\'s tempremental to start when warm as a result (made worse by eliminating the PRC solenoid - but hey - it was a learning curve). A little bit of throttle blipping see\'s it running...

infernal · May 23, 2011, 04:09:17 PM

Hello all!

I did some pulls today and recorded a crappy video of my gauges...

It seems that up to 0.7bar the AFR stays in the "oh sweet" levels, but after that it climbs quickly to the "oh ....!" levels!
I feel grateful that I didn\'t detonate... Or at least I think I didn\'t! :eek

Here is the video.
Any thought would be very welcome, as I don\'t have a clue of what might be the problem...
I have numerous fears. Is it maybe that my fuel pump is not fed correctly when on boost? Is it possibly that I was shipped the Low Pressure Walbro pump instead if the High one?
Or I\'m thinking if it\'s my ACV that possibly malfunctions and releases port air... Prior to the pulls, when idling my AFR was 16-17 due to the port air. Now, after the pulls it is 12-13, which means no more port air. OMG what happened in there under the UIM...
:flamed
Please shed some light to a n00b\'s boosting nightmare! :Hammer:Hammer:Hammer
:o

Thanks!

yiug412 · May 23, 2011, 11:16:01 PM

Quote from: Prof;764337Secondaries are only ever running above 3500rpm and on boost, never any other time, so the primaries are doing the bulk of the work. Without knowing your setup, it\'s my guess the fuel pressure isn\'t there at the top end cancelling out the larger injector benefit - but like I say, it\'s conjecture...

It\'s why I went down the emanage route - as you can log so much stuff before during and after making mods - so you can actually see what\'s happening. And a fuel pressure gauge is a worthwhile investment too - for dyno testing.

AFR\'s on idle - low to mid 13\'s are fine - that\'s about stock anyway. Only ever see the 14\'s on cruise between 1500 and 3000 rpm when the narrow band lambda actually does something , It\'s not used for idle (like on other cars) and not used for top end fuel correction either - that\'s all MAF and latterly MAP based with tables.

I\'ve managed to tune my idle AFR\'s to about 14 when warm, but it\'s tempremental to start when warm as a result (made worse by eliminating the PRC solenoid - but hey - it was a learning curve). A little bit of throttle blipping see\'s it running...

I think it may be due to my stock pressure gauage never read correctly. I have only hit fuel cut once after my mods and i always get up to 0.8 or 0.9 bar WOF

and it also may be due to my old fuel filter that i have no idea how old it is...

I actually have a PFC but im waiting for Pete to help me out on the datalogit

btw where has Pete been these days? havnt heard from him for ages.

infernal · May 23, 2011, 11:35:37 PM

Quote from: infernal;764345Hello all!

I did some pulls today and recorded a crappy video of my gauges...

It seems that up to 0.7bar the AFR stays in the "oh sweet" levels, but after that it climbs quickly to the "oh ....!" levels!
I feel grateful that I didn\'t detonate... Or at least I think I didn\'t! :eek

Here is the video.
Any thought would be very welcome, as I don\'t have a clue of what might be the problem...
I have numerous fears. Is it maybe that my fuel pump is not fed correctly when on boost? Is it possibly that I was shipped the Low Pressure Walbro pump instead if the High one?
Or I\'m thinking if it\'s my ACV that possibly malfunctions and releases port air... Prior to the pulls, when idling my AFR was 16-17 due to the port air. Now, after the pulls it is 12-13, which means no more port air. OMG what happened in there under the UIM...
:flamed
Please shed some light to a n00b\'s boosting nightmare! :Hammer:Hammer:Hammer
:o

Thanks!

OK update, I removed the airpump belt and did 1-2 more pulls. AFRs still start to rise above 12:1 and thus I didn\'t push it. :2Confused

PS Sorry yiug412 for hi-jacking your old thread!

yiug412 · May 24, 2011, 01:40:29 PM

Lol it\'s fine. U got some good question as well ae. Btw does ur afr rise up to high 12s? Plug in ur laptop to the wideband controller and logit. And set warning to 13 then do some boost that will give us a better view

yiug412 · June 04, 2011, 11:34:17 PM

another question related to boosting, When i step on the floor in third from low rev, i can feel the turbo kicking in around 3500 rpm then at 5000rpm it has a very sudden rise in power that always make my wallet fly all the way back to the car, does that happen to other people\'s TII?

my set up is 3 inch full exhaust, possible S320 turbo or similar and FMIC. no boost controller and it boost up to 0.9 bar on my gauage. AFR reads around 12\'s when boosting.
Cheers
Louis