Hey guys I'm a bit worried. I thought that on the 1G I would be able to run 20-22psi on pump gas but it seems not.

I'm using stock 7.8:1 pistons, Evo VIII FMIC, no coolant lines on the TB, anti temp gasket between intake mani and head, 2.5" IC piping, 2.75-3" exhaust, BR7es plugs, a plate that avoids engine bay hot air to get sucked by the air filter and using 98 octane gas wich should be like 91-93 octane in USA.

I attach the timing map and fuel map i'm using (they're the extended version ones)
Usually I'm getting knock at 4-4.5k on the 2.63-3.00 g/rev range. around 10 counts and then it goes away at around 5.5k but timing drops a bit too (to 9º at 5k if i remember correctly).

(You can see the attached image 5 posts below, Imageshack deleted the original image I don't know why)

As You can see the A/F is already pretty rich, so it's not a lean problem.
If I add a bit more fuel with the SAFC the knock dissapear unless I rise the boost again over 18psi.

Any ideas of what's wrong? Or is that completelly normal?

I thought I could run more boos easily with my setup but it seems not.
Are the timing table correct on that 2.63-3.00 g/rev 3k-7.5krpm range?

What size injectors are you on and what is your IDC? Maybe you are outflowing them.
Also you have to remember the 1g runs a very aggressive timing map, so I would pull a degree of timing or two and add some fuel and try that.

That's where they seem to always show the most knock. Pull 2-3 degrees.

Also, it would be nice if you'd update your profile with your car details. I know you listed most of the details in your post, but it's nice to have the info in your profile.

are you using stock injectors?

What are you using to tune with? Since you said "Extended Fuel and Timing maps" and know what g/rev area you're in I'll assume you're doing the EPROM editing yourself?

Make sure there are no boost leaks... That will reek havok on your tune like nothing else.

It's all a balancing act. I can't view your log or whatever you posted because I'm at work and they block imageshack and you didn't upload it to the site. But, if your getting knock in a particular area it's either from too much timing, not enough fuel, or too much boost. Keep two of the three at a constant level and adjust one of the other ones. So, since you're getting knock in the 2.75-3.00 g/rev area between 4-4.5k areas take some timing out. Then, pull a log, and if you're still getting knock add in some fuel at the same spots your getting knock. I didn't read that you have a wideband. I would get one and try to keep it at the leanest 10.5:1 AFR on pumpgas only. I wouldn't be EPROM editing without a wideband. It's just not smart.

With a FMIC and 650cc injectors I got away with 22 psi on pumpgas before I went with water injection. Now, that I have water injection I pretty much can run whatever I want for boost and get around 11.5:1 AFR.

Sorry, I just updated my profile.
Yes I'm burning my own chips and I do have a wideband. And I'm using a palm and MMCD for logging.

I'm using 720cc injectors, Got them used from a guy, maybe one of them is flowing less than the others and producing knock?

I just upload the same image here so You guys with blocked Imageshack can view it. Is not a log, it's just the fuel and timing tables I'm using just if anybody want to take a look to see if the timing is too high or something.
As you can see I'm under 10:1 AFR on that area.

I'm using a PLX M300 wideband and the display reads "RICH" as below 10:1 it doesn't show any value other than the word "rich".

No boost leaks at all, tested few weeks ago.

The timing on the area where the knock occours (4k) is 12degrees, then the knock counts rise to 7-10 and the ecu pulls timing leaving at 9 deg (5k) after that knock is back to 0 and the timing rises again.

If I add a pair or three notches to the rich side of the SAFC I can get rid of the knock, but who knows what AFR I'm running then, probably 9.5???

Could I have a bad knock sensor? It hasn't been replaced in 18 years.

Could be rich knock... BTW, what logger are you using? Most don't tell you where you're at on the map. Just curious. I normally have to guess by what my timing and AFR looks like.

First off some things to try... Lower the timing around that area down so you don't knock and get your AFR in line with a target like 10.5-11.0:1 There's no reason you should have to be running that rich (9.5). We're not trying to make a lot of power here, we're just trying to establish a consistant AFR. Also don't do it on the SAFC. Zero that out and edit your fuel in the fuel map in the bin. Once you're pulling a log that shows a consistant 10.5-11.0:1 AFR with no knock, then you can go back and try to fine tune the timing. What you are doing on the SAFC is lying to the ecu about the airflow coming in and that will also put you higher or lower on the fuel/timing maps than what you really are you want the airflow signal as unmolested as possible. Tune with the EPROM like you don't even have the SAFC. Then when everything is good you could probably sell it or just use it for minor, very minor changes. And at that point it's pretty much useless.

Here's what my timing and fuel tables look like for pumpgas and water/meth (Remember that the AFR that is in your fuel table you might not acually hit when you are logging. Real world is always different than theoretical). This nets me a good 11.5:1 AFR.

I have to agree with everything projectGs said. I would start by eliminating the chance of rich knock, then if it's still doing it, maybe back a couple degrees off where it starts to knock and ramp it up as the RPM's increase by as much as you can for the best burn at higher RPM's (but it seems like you have a decent grasp on what you're doing). ON a stock 2g bottom end at 4 - 4500 RPM, 12 - 14* was about peaked out on my car on pump gas. and with a stock 1g bottom end ( 6 bolt) I was able to bump it up to between 16 and 18* in the areas you're having your issues. Have you tried running a can of seafoam through it to see if there's maybe a huge amount of carbon on the pistons and in the combustion chambers? I might help, it did quite a bit for me after 5 years of running my last motor on petrolium fuels.

Looking at your timing table it may be that you're having a bit much timing in the lower boost areas setting the engine up for pre-ignition by the time she's spooled up. They aren't too far off from mine, but i don't have a stock mitsu knock sensor. I've run my engine by feel and performance along with it's tone and although i did have a few degrees of excesws timing with no knock control for well over 7-8 years I never popped an engine due to agressive timing or detonation. There's along beena theory than an engine runs it's hardest while slightly detonating or being right on the verge of detonation, and to be honest i put some faith in that after my own decade of tuning experience. More so in the lower - mid RPM's where torque reigns supreme, but i have nothing scientific to back it up, just the good ol'e but dyno and a hell of a track record for cars eaten even when my setup was simple and just fully programmable (and to be honest it's still simple to this day, i just made it look pretty in the engine bay).. I"m now runing a built engine for the first time (my last best was a 1g rod 6 bolt with ARP bolts and some JE 8:1 pistons... Now i'm running eagle H beams and 9:1 pistons. I have actually witnessed true knock on the new motor even with E85, the 9:1 pistons are very picky about the timing curve, not so much the peak numbers but the rate at which the timing ramps down while boost in setting in and spooling up, that's why i mentioned these areas in your manp because i've spent a lot of time on them with my own tune lately.

Good luck, and to be honest, a little knock at 18PSI on pump isn't that out of the ordinary

IMO, anything over 15psi will require at least 10.5:1 or better, check your tables again.
Looks like rich knock.

Hi PrOjEcTGS, thanks for the reply.

I'm logging using a palm and MMCD 1.7.
There's a code mod that allows You to log the row (load) You're at, it's very useful.

I was playing with the SAFC just as a quick test to see if the knock was because of running too lean or too rich. As soon as I gave it a bit more fuel (but probably timing also got afected by this) the knock disappeared.
Normally I have the safc zeroed and I adjust the afr by burning chips, but for testing purposes or as a safety option I leave it there.

I'll try to lower the timing and set the afr to 11-10.5 all the 2.6-3.0 load range under boost and see.

About Your tables, I don't thing they are useful for me as You use Meth/water injection and I don't, but at least would be useful to see the increasing/decreasing ratio between cells.

I did adjust my injector settings to get as acurate AFR as I could. The PLX reads pretty much the exact value as the AFR table. Well maybe +-0.2 AFR difference but that's pretty acceptable I think.

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Hi Turboglenn, The engine has only 2000miles after a complete rebuild, so carbon buildup is not the problem, unless the dyno oil I was using for 1000 miles left a lot of carbon there.

Could You give me Your timing and AFR values? I would like to try them, lowering the timing a bit first.

Rob10_99, what do you mean by better? leaner or richer?


Thanks to all.

I'm sure he means leaner. Even the high 10s is considered rich for 91 octane. I've had several cars knock because of this while tuning them. DSM and non DSM. Not sure what the difference is since you're on European 98 octane, but I'd think you'd be able to run a 11.5 AFR no problem if it is similar to US 91 octane. I'd really aim for 11.5 on your tune and then decrease timing as everyone has mentioned and I bet you'll be able to see 20psi.

Oh not sure if this would help, but personally since you're barely getting to 20psi I would still be running BPR6ES plugs and not the 7s. Might not hurt, but might be worth trying also. Maybe someone else will chime in on the plugs?

Good Luck.

I would definitely lean things out as said and see how that goes. Maybe pull a degree of timing or two in the 4-4500rpm area as said as well.
I would probably run the 7es plugs for 18psi+

I just copied the AFR table that ProjectGs posted above and I'll try that timing table I post here. Let's see what happens. Hope it was rich knock.

If somebody running pump gas had an extended timing table that I could take a look It would be great.

Yea that looks like a pretty good starting point.

You should try to get a copy of a 2g or evo timing table and copy the whole thing.

I have the timing maps and eprom bins of the 2G gst I had before this Talon.
Do You think that 2G timing maps are any better than 1G specific ones?

My timing maps were based off of the 2g maps at first. They were a little too conservative. Then, I started using extended maps that I modified to fit my needs.

Ok, I get it.

Would You guys mess with the knock sensor?
I mean, it has 18 years, so don't know if overtime those things go wrong or something.

Also how tight do You guys set the sensor? I was told to not tighten it very much, not as much as the manual say. But the other day someone told me that it's just the oposite, If I have it not tighten it enough it may pick up more noise than it should.
Is that correct?

I think the torque on the knock sensor is like 11 lbs. You can tell if yours is bad by the goo in the middle. If it is gone or mushy get a new sensor. BTW I would raise the timing table in the upper load level. Start at like 10 at 4500 and end at 15 at 7000. That is still very concervative. I use load based tuning on my 1g with a SD conversion and that was about where I started tuning the other day. You will add more most likely but it is still a safe start.

selmerguy said:

I think the torque on the knock sensor is like 11 lbs. You can tell if yours is bad by the goo in the middle. If it is gone or mushy get a new sensor. BTW I would raise the timing table in the upper load level. Start at like 10 at 4500 and end at 15 at 7000. That is still very concervative. I use load based tuning on my 1g with a SD conversion and that was about where I started tuning the other day. You will add more most likely but it is still a safe start.

Click to expand...

I'll never reach that last row, those tables are Extended maps (double load range than stock), not the regular maps that max out at 15psi.
The last two rows on the extended maps are for boost over 30psi aprox. so I'll never use those cells in my life.

mikyrc said:

I'll never reach that last row, those tables are Extended maps (double load range than stock), not the regular maps that max out at 15psi.
The last two rows on the extended maps are for boost over 30psi aprox. so I'll never use those cells in my life.

Click to expand...

Oh.. Ok. Then yeah your timing looks like a good start I guess I dont understand the numbers in the left clum. I guess they are load but they lok different than the way we have ours setup.

Yeah, the left column is just the Load value label. The stock maps I think only reach the 2.25 value as much.

Here it goes a log I did today using the timing table I posted and the Fuel map provided by >PrOjEcTGS<-. By the end of the log the boost was almost 20psi due to a bit of boost creep.

I quit before reaching 7k 'cause it was raining and there was a bit of traffic, so I didn't want to kill myself.

What do you guys think?

What should I do now?
Lower one degree of timing on the areas just and before where im getting knock?

Just either drop timing like you said, or try and add some fuel to eliminate the knock.