Switch Position Fuel Correction Ignition Correction

0 0 0
1 +3.1% 0
2 -3.1% 0
3 +6.3% 0
4 0 -2.72°
5 +3.1% -2.72°
6 -3.1% -2.72°
7 +6.3% -2.72°

Ok...those are the settings at each position.

Can someone explain what the retardation of the timing would accomplish?

My 951 seems to belch a little blue-white smoke under heavy throttle. I suspect that the car is running a bit rich, and also a bit of turbo blowby. But I want to eliminate the richness, to better estimate which is which.

Could someone maybe explain a bit about troubleshooting fuel settings?

Another question. I live at high altitude, over 5000 feet. Should I make adjustments for this? The car runs great, but I suspect it has more to give if it was tuned properly.

 

I think that there's a couple of previous threads that would answer your question more in depth, but I believe this switch is called the fuel quality switch and therefore is meant to be adjusted for the fuel quality of the country or region. For significantly lower octane fuel you'd probably want the retard to prevent detonation at the higher load/boost conditions. You car has an altitude sensor but you might try the -3% fuel with no retard switch anyway.
Good Luck,
Russ

 

are you sure that the list you have posted is correct ? the reason i ask is because the one on the faq list has the settings like this

1- stock
2- +3%
3- +6%
4- -3%
5- 0 -3 degrees
6- +3% -3 degrees
7- +6% -3 degrees
8- -3% -3 degrees

and if your list is the accurate one then i adjusted my dme wrong and that would be the reason i failed the smog test again

 

Instigator,

The faq has the wrong setting, Water944T has posted the correct ones. You can also check them out at the <a href="http://www.bonnevillemotorwerks.com/fqs.html" target="_blank">Bonneville Motor Werks Page</a>.

Water944T,

[quote] Can someone explain what the retardation of the timing would accomplish? <hr></blockquote>

As Russ said, it's the fuel quality switch and retarding the timing would be useful for lower octane fuels to prevent pre-ignition.

[quote] My 951 seems to belch a little blue-white smoke under heavy throttle. I suspect that the car is running a bit rich, and also a bit of turbo blowby <hr></blockquote>

Since it's blue-ish smoke (oil burning) It could also be your valve stem seals. Do you have any oil it you intake tract (intercooler pipes) that would point to bad turbo seals?

[quote] I live at high altitude, over 5000 feet. Should I make adjustments for this? The car runs great, but I suspect it has more to give if it was tuned properly. <hr></blockquote>

I don't think there is much you can do easily, The fuel injection should compensate for the altitude. Also, when your under boost, you intake manifold is at the same pressure as it would be at sea-level, your turbo just has to work harder to get it there. I'm at a 7200 ft elevation here in Los Alamos and the atmopheric pressure is about .8 bar versus what would be approximately 1 bar at seal level.

Where do yo live in NM?

Rob <img src="graemlins/wave.gif" border="0" alt="[byebye]" />

 

Yeah, blue smoke is usually not a rich mixture. It's most certainly a sign of oil. Perhaps even your turbo seals might be going. High-altitudes make your turbo spin faster for the same boost, so maybe your turbo has some premature wear from all this work.

 

thanks Rob, now time to get whom ever posted the faq to change it

 

Water944t,

A rich mixture would show as black, sooty smoke.

Be very careful about leaning out your motor, could be disasterous! Check with a exhaust gas anlyzer BEFORE you lean your mixture.

 

Hi folks - While I agree with whats been mentioned so far about oil burning - remember that oil in the intercooler pipes can also be caused by excessive blow by. The oil seperator does dump back into the intake before the turbo....
too many folks assume that oil in the intercooler tube is only caused by bad turbo seals.

Chris White
<a href="http://www.944enhancement.com" target="_blank">944 Enhancement</a>

 

I am in Las Cruces, Rob.

I checked my intercooler pipes, a little bit of oil, no more than 4-5 drops would pool up into. I do get some white/blue smoke when I really get on the throttle, I had assumed it to be a little blowby from the turbo.

Valve guides? Is this a home repair for the moderately wrench capable? I do not have confidence in my local German repair shop.

I have noticed that the lifters are ticking pretty loud too. I read that varnish build up can cause this, and can be cleaned? Could this relate to bad/failing valve guides?

You can tell I am not engine savvy.

The car runs great, boosts like its been kicked, but I have this embarrassing smokey fart in public.

I also have no idea when the timing belt was changed, but a visual inspection shows a pretty new looking belt, with almost no wear, same for the teeth on the gears. I bought the car cheap from a local used car guy, who had no idea what to do with it. But it had no papers at all.

The car has never been wrecked, and the carpets under the floormats are pristine. I have replaced the clutch (and related bearings, ect.), oil sending unit, and done a whole lot of TLC maintenence. It would be nice to be able to ask PO about the car.

One of the reasons I though tit might be a bit rich was the carbony dry residue that is in the exhaust pipe. I noticed it first when the car spit a bunch of it, mixed with morning dew, onto my pants before work one morning. It could be burnt oil I guess, but it doesnt seem to have a oily texture at all.

Thanks to everyone for the advice.