Duke

I've emailed Danno about this but I know he's a busy person so I'm also asking here...

I have K27 18 psi chips and wondering about the FQS settings for ignition. I suppose I don't need to use the ignition retard setting because the retarded ignition for 18 psi should already be in the chips.

But I want to make sure! I don't want my car start pinging and destroy my engine now that I have an "undestructable" head gasket..

GWTurboS

Duke,

This is sort of a cross-post from another thread, but I am also running the 18psi Guru chips, Reliaboost (no CV), shimmed wastegate, 3 bar FPR combination on my 88 Turbo S. I have the FQS switch set at 0. I am getting a little detonation in 3rd gear as I apply full throttle and the revs climb above 4500-5000. Of course, the 91 octane gas in California is not very good, so this weekend I am going to try using FQS position 4 which is 2 degrees of timing retard.

In the past, I have always mixed about a 15-20 percent Toulene to gasoline blend to raise the octane. This also solved any detonation issues. However, I did not have time to do that this week.

Best Regards
Greg W.

Jake951

It depends on what size injectors you are using. For stock injectors (34 lb/hr) it's position 0 (fully CCW). For 55 lb/hr it's position 1 (one click CW). For the 18 psi chips it's recommended you use at least 55 lb/hr injectors.

Duke

Yes I have 72 lb/hr so I will adjust the switch for that, but what I'm wondering is what ignition setting to use.

Jake951

Danno would be the most qualified person to answer the question. However, I think he has reprogrammed the function of the FQS to work with the Guru chips and different injector sizes, so the stock function of the FQS, which you can look up on his 951 Racer X Web site, probably is not applicable. I have no idea if the FQS would even affect spark advance/retard with Guru chips.

pk951

GWTURBOS

You should go on a dyno to see what you're AF ratio is running 18 psi with 91 octane that's a bit scary.

91 octane is like water.

the more you retard timming you're EGT will go up.

Bones944

I received this in an email from danno:



I would set the FQS switch to the retarded FQS settring at #4 just to
be safe. This will allow you to run 18psi on 91-octane pump gas. The
stock FQS setting #0 should only be used with a 50/50
pump-gas/race-gas blend at 18psi.

facboy

wow! need to know this, i do.

Waterguy

The instructions I got with my version 9 chip says:

"The latest GURU Racing chip version-8 has selectable injector sizes
and ignition maps. It uses the FQS switch to select injector-sizing
and alternate ignition maps. The FQS switch is the 8-position one on
the DME, you can get instructions on how to adjust it here:
http://members.rennlist.com/951_racerx/FQS-adjust.html .

The FQS switch adjusts as follows:

FQS INJ IGNTION
---------------------------------------------------
#0 34.6lb 0 stock
#1 55.0lb 0
#2 65.0b 0
#3 75.0lb 0
#4 34.6lb 2.0 degrees retard
#5 55.0lb 2.0 degrees retard
#6 65.0lb 2.0 degrees retard
#7 75.0lb 2.0 degrees retard"

HTH

toddk911

"stock FQS setting #0 should only be used with a 50/50
pump-gas/race-gas blend at 18psi."

Ahhh, is this true Danno??? As I have the 18psi GURU chips, stock injectors and using 0 setting.

Bri Bro

You are increasing the boost from 10 PSI to 18 PSI. The effective compression ratio WILL increase and higher octane fuel will be required to stop detonation. The car WILL see an increased load to all the bearing and gaskets. Remember, increased HP is related to increased risk. Nothing is for free. Got a WB or EGT sensor?
Go for it ..but understand the risk!

Duke

But if the retarded setting is required on the 18 psi chips it seems it's only the fuel maps that are different from the 15 psi chips and that doesn't sound right.

Danno?

facboy

hum...my afr on gurus at 18psi goes hella rich in the mid-range (compared to everything else). have a squizz:




Now if you look at the boost curve, it's actually boosting at its peak in this area, so what gives? The dyno guy (as I've mentioned before) says there are a couple of rattles (detonation he thinks) right as the turbo spools up, which then disappear as the knock sensor does its thing and the dme/klr retard timing. question is, could this retarding be responsible for that very rich area?

btw, the red run is at 18psi, the blue is at 16psi. the dyno guy says he heard the detonation on both runs.

cheers,

chris.

slim_boy_fat

What the heck is going on, i thought that if you run standard fuel (NOT Race) and have standard injectors then you run position 0....

I thought that the ignition retard was onl yif you were running race fuel....

I got the same instructions as Waterguy...

Come on whats the hecks going on....

Duke

For race fuel you use the ignition advanced setting with the region plug, as I understand it.

But the question still remains..