I may have figured out my detnation and lean AFR problem.....

[tacbear]

For those that don't know I ran 3 times at Steele and had to let off at 1100' for detonation one time and lean AFR twice. (tried 3 different tunes).

Well I just found out that the fuel pump that I installed was not a SVT Focus pump, it was a regular Focus pump. So I am running a 381.5 rwhp motor on a 90 rwhp pump. Does anyone hear think that might be my problem??

[QWKSNKE]

I had a guy who WORKS the parts dept at a Ford dealership try to tell me that all focus pumps were the same.

[QWKSNKE]

by the way, could you see your fuel pressure when making those runs?

[Italian LX]

If that's your problem then you should've seen a drop in fuel pressure.

[The Rock 326]

When you figure out the detonation problem, let me know too!

[tacbear]

by the way, could you see your fuel pressure when making those runs?

I don't have a FP gauge, AFR was fluctuating back and forth from 12 to 12.9.
This is from the Ford Parts "Guru" on Modular Depot:

part #'s are as follows> Focus SVT 3S4Z-9H307-BA which was replaced by a 3S4Z-9H307-BC
regular Focus > build date before 12/6/01 > 1M5Z-9H307-AA which was replaced by = 1M5Z-9H307-AB > then went to a 1M5Z-9H307-AC > and that went to a 1M5Z-9H307-CA
regular Focus built from 12/06/01 > 2M5Z-9H307-AA then that was replaced by a 2M5Z-9H307-AB which went to a 2M5Z-9H307-AD


ME:

So Randy if I have the Focus Pump part#1M5Z-9H307-CA, is this for a NON SVT Focus and am I running the wrong one for a Supercharged GT??

ANSWER:

that is correct, you have the wrong pump. please do not use that pump wth your combo.

[EZ SPEED]

AFR was fluctuating back and forth from 12 to 12.9.


:eek:

[QWKSNKE]

:eek:

:werd:

It would scare me just seeing the a/f run at 12:0. :shake:

[The Rock 326]

I don't have a FP gauge, AFR was fluctuating back and forth from 12 to 12.9.
This is from the Ford Parts "Guru" on Modular Depot:




ME:



ANSWER:

Did you get yours from MPH??

[tacbear]

Did you get yours from MPH??


NO, you probably have the right one.

[The Rock 326]

NO, you probably have the right one.

But I have the same problem you do.:think:

[Italian LX]

But I have the same problem you do.:think:
You do? :think:

[The Rock 326]

You do? :think:

Well, the going lean, and detonation part.

[coupe]

:( FWIW, I found some good prices on pumps, not Walbro, but seemed pretty decent upon inspection...and not loud at all in car.
I got a regular 255lph 5.0L, In-tank for $69.99 :D

[NightHawk756]

Well, the going lean, and detonation part.

Your still having trouble Rich? Even after the last attempt to fix it??

[QWKSNKE]

Well, the going lean, and detonation part.

So you have the right amount of fuel pressure but you are still going lean?

Sounds like you need another tune to richen it up

[Wall96cobra]

So you have the right amount of fuel pressure but you are still going lean?

Sounds like you need another tune to richen it up


that's what I was thinking, it may have been fine on the dyno but when the car is on the street it's under more of a load so you need more fuel.

[Italian LX]

that's what I was thinking, it may have been fine on the dyno but when the car is on the street it's under more of a load so you need more fuel.
:agree:


Also, how high was your MAF voltage at the top of the pull? If it was anywhere near the max, then you could likely be pegging your MAF due to the colder air.

You're intake air on the dyno was likely warmer -- not only because of the general weather conditions, but also due to lack of circulation (especially if the doors are closed) -- the warmer air being less dense will register a lower voltage.

[TheJeanyus]

Also, how high was your MAF voltage at the top of the pull? If it was anywhere near the max, then you could likely be pegging your MAF due to the colder air.

You're intake air on the dyno was likely warmer -- not only because of the general weather conditions, but also due to lack of circulation (especially if the doors are closed) -- the warmer air being less dense will register a lower voltage.
That's what I was thinking, too. :yup:

[Scothew]

Yeah I am thinking Rich's car may be adding to much timing or the much denser air is the cause of it, cause most of the time he has the problem is to and from work, which is like 9pm at night and 7am in the morning, so its significantly colder than when the dyno was done.

If Doug takes 2 degree's out, I think he'll be close to set assuming his fuel pressure is fine.

[The Rock 326]

Yea, the F/P seems fine(in the 40+PSI range @ WOT). I'm going to get with Doug, and add a 3rd. tune(cold weather). I woud like to take out 2 degrees, and add some fuel. I think the dyno temp has a lot to do with it. The day of the dyno, it was quite a bit warmer(60+ degrees). The days it detonated, it was in the 20-30 degree temp range. It didn't seem to detonate until I got it over 5lbs. of boost. I drove it on one of the warmer days 2 weeks ago when it was in the 70's, and got in it, and it seemed to do fine.:shrug:


Whit, is that about the same with yours?? Didn't yours drive fine on the warmer days??

[QWKSNKE]

Do you have your dyno graphs? I would like to know what your a/f is tuned to

[tacbear]

Do you have your dyno graphs? I would like to know what your a/f is tuned to


Both of our cars' AFR run pretty straight from 11.5 to just under 12. Up until I went to the track whenever I would get in the boost my WB Commander was rock solid 11.8-11.9. Also I recieved my new pump today (it is the complete assembly-bucket,sending unit and fuel tank cover) and the "bucket" assembly is completely different from the one that Dave got me, whichs tends to confirm that I have the wrong pump!

On the Dyno Sheet it looks like the AFR goes over 12, but I laid a straight edge across the graph and the AFR is at 11.5 at 4000 rpm and just touches 12 at 5200 rpm. The blue line was my final tune.

[QWKSNKE]

If it were me ( and this is the way I do mine) I would have it tuned where it is no higher than 11.5-11.6 in the upper rpms on the dyno.

Generally speaking, it seems that you can usually get away with a 12:1 a/f up until 4000 rpm then have it slope down to 11.5 around 5500 and hold that flat. This seems to work well to help battle potential lean detonation when on the road.

[tacbear]

If it were me ( and this is the way I do mine) I would have it tuned where it is no higher than 11.5-11.6 in the upper rpms on the dyno.

Generally speaking, it seems that you can usually get away with a 12:1 a/f up until 4000 rpm then have it slope down to 11.5 around 5500 and hold that flat. This seems to work well to help battle potential lean detonation when on the road.

I agree with you 100%.

[QWKSNKE]

That's a cool pic Whit :nice:

[The Rock 326]

Not trying to jack your thread Whit.

Here's my graph for comparison. Dunno if you can tell the AFR or not??

BTW, nice pic of the Stang!

[QWKSNKE]

My graph. Dunno if you can tell the AFR or not??

From what it APPEARS, your a/f could stand to be dropped down a little as well.

[The Rock 326]

From what it APPEARS, your a/f could stand to be dropped down a little as well.

I'm gonna get with Doug, and dyno it again.

[Wicked]

Neither one of you have intercoolers right?

What is your timing? A lot of tuners like more timing and fuel, and some like less timing and less fuel. Its all a balancing act. You may need to take timing out of it, not fuel.

My car is kinda like a poster child for how long a car can run with a pegging MAF and 12.5-13:1 AF at high rpms with 13 psi of boost. No pinging ever, cold or hot. I am also running the lowest timing I have ever seen on a car like mine and I believe that's the key.

Chris Johnson, president or whatever of Superchips and found of Johnson Motorsports(JMS CHips), tunes like this.

My point is, a 12:1 AFR is not lean at the boost levels you guys are running and timing makes heat too.

My .02.

BUT, because of your pump situation, you my actually be running lean. :-D

[The Rock 326]

Neither one of you have intercoolers right?

What is your timing? A lot of tuners like more timing and fuel, and some like less timing and less fuel. Its all a balancing act. You may need to take timing out of it, not fuel.

My car is kinda like a poster child for how long a car can run with a pegging MAF and 12.5-13:1 AF at high rpms with 13 psi of boost. No pinging ever, cold or hot. I am also running the lowest timing I have ever seen on a car like mine and I believe that's the key.

Chris Johnson, president or whatever of Superchips and found of Johnson Motorsports(JMS CHips), tunes like this.

My point is, a 12:1 AFR is not lean at the boost levels you guys are running and timing makes heat too.

My .02.

BUT, because of your pump situation, you my actually be running lean. :-D


As far as mine, I want to take out timing, and add fuel. Pretty sure the Street tune is @16 degrees. I think the Race tune is set @ 19.5 degrees, that is of course with race fuel.;)

I still think this has a lot to do with the outside temp.:popcorn:

[QWKSNKE]

I still think this has a lot to do with the outside temp.:popcorn:

yes. there are tables in the EEC in regards to timing and and incoming air temp.

[rtusnake]

Neither one of you have intercoolers right?

What is your timing? A lot of tuners like more timing and fuel, and some like less timing and less fuel. Its all a balancing act. You may need to take timing out of it, not fuel.

My car is kinda like a poster child for how long a car can run with a pegging MAF and 12.5-13:1 AF at high rpms with 13 psi of boost. No pinging ever, cold or hot. I am also running the lowest timing I have ever seen on a car like mine and I believe that's the key.

Chris Johnson, president or whatever of Superchips and found of Johnson Motorsports(JMS CHips), tunes like this.

My point is, a 12:1 AFR is not lean at the boost levels you guys are running and timing makes heat too.

My .02.

BUT, because of your pump situation, you my actually be running lean. :-D
Whats your timing at?

[Wicked]

Whats your timing at?

11 total across the board.

[tacbear]

11 total across the board.

I am pretty sure my "Race Tune" is 14 deg.

[Wicked]

I am pretty sure my "Race Tune" is 14 deg.

That's not very aggressive at all.