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turbo84voyager
03-09-2009, 06:49 PM
Attached is the 2.5 g-head cal I am running on my 89 turbo mini with a 46 trim hybrid, header, open exhaust, intercooler, and charge sensor. The cal is based on Moparzrule cal but was detuned a little and I made a few changes which improved starting and driveability on my van. My van did not like all of the timing in the original cal. With this cal the engine sounds better and the plugs look better as well. I am running about 8 degrees of initial timing. I would start with 10 degrees and either advance to 12 or if you get the CEL knock back off to 8. The knock sensitivity is also more sensitive on this cal. I am running 55psi of fuel pressure and RN9YC Champions.

Update:

I am currently running Autolite 62's (Champ RN7YC) and the engine likes this plug much better than the 63's. I am going to try the AR51 ( non resistor version of champ RN6YC). I will post a message with the results. After reading the 62's I dont see any problem going 1 coolder and this would be good since the 62 is obslete.


*** There is no boost control on this cal ***

If you are looking for every last bit of performance this cal is not for you, it is more for a daily driver than a race car.

PM me if you have any questions

turbovanmanČ
03-09-2009, 07:21 PM
Nice, alot of advance there, much more than the G-head cal I had.

turbo84voyager
03-09-2009, 08:31 PM
The advance lowered my EGT's quite a bit and it is not a dog like it was with a stock computer. I have to thank Matt and Rob for all their work getting the base cal as good as they did.

turbovanmanČ
03-09-2009, 09:16 PM
The advance lowered my EGT's quite a bit and it is not a dog like it was with a stock computer. I have to thank Matt and Rob for all their work getting the base cal as good as they did.

I compared it to my old G-head Rob cal, Matt's/yours are way more aggressive but when your doing it over the net, hard to get it right. No offense to Rob, :nod:

I had bad EGT's on the highway at cruise, :(

turbo84voyager
03-09-2009, 10:59 PM
I originially bought a FWD stage 5 g-head computer and even the second chip, I was easially able to hit 1650 - 1700 degrees cruising even with the distributor set to 18 deg. The other problem is the van was a real pain to start with the cal. It would stay running after 6 attempts. This cal is very hard to get right so I cant hold anything against FWD and I can understand them being worried about putting soo much timing in and having people blow their engines. I was ready to pull the head but I ran into matt at carlisle last year at Chris' (TU) booth. He burned a chip and made a few changes to the cal for me. I then went and fine tuned it for my van. The highest I ever had it with this cal was 1610 climbing a long hill at 75mph and not in boost. As soon as I went into boost and it richened up it droped down to the 1400's. I spent most of my time cleaning up the cold starting with this cal. It was a little too rich when it was cold and it was taking very long to warm up. Now it leans out pretty quick when it is cold and warms up quick. You can notice this if you look at my cold A, B, C.

ShelGame
03-09-2009, 11:56 PM
I compared it to my old G-head Rob cal, Matt's/yours are way more aggressive but when your doing it over the net, hard to get it right. No offense to Rob, :nod:

I had bad EGT's on the highway at cruise, :(

None taken. I wanted to be conservative. At the time, I was doing another 2.5 G-Head cal and was having detonation problems at only slightly more advance than what I used in yours and Moparzrules (original) cal. To me, it seemed like a knife edge to balance a 2.5 G between high EGT's and detonation. I guess most 2.5 G's can take a lot more advance than I originally thought...

turbovanmanČ
03-10-2009, 02:39 AM
None taken. I wanted to be conservative. At the time, I was doing another 2.5 G-Head cal and was having detonation problems at only slightly more advance than what I used in yours and Moparzrules (original) cal. To me, it seemed like a knife edge to balance a 2.5 G between high EGT's and detonation. I guess most 2.5 G's can take a lot more advance than I originally thought...

Exactly, better safe than sorry, :thumb:

It still ran great, just not fast enough, lol!

turbo84voyager
03-10-2009, 11:27 AM
Rob,

When were you having detonation issues (boost or no boost)? Did you hear the detonation or were you getting the CEL? Mine has a very slight knock sound but when accelerating and not in boost, I never get the CEL and it didnt make a difference even when I pulled timing out and my plugs look fine thats why I dont know if its detonation or something else because its not the high pitch ping I am used to hearing, my old 2.5 TBI sounded the same way accelerating so I am assuming its just the sound of the engine.

ShelGame
03-10-2009, 11:30 AM
Dunno, I didn't hear it myself. It was reported back to me by the guy I was doing to cal for. But, he did have timing being pulled by the knock system. Could've easily been another issue, though (bad sensor, etc.).

turbo84voyager
03-10-2009, 11:35 AM
Rob,
The CEL comes on when timing is being pulled right? or is it being pulled before it lights?

Thanks,

Justin

ShelGame
03-10-2009, 11:39 AM
Nope, CEL comes on whenever there is knock retard on any cylinder...

turbovanmanČ
03-10-2009, 01:53 PM
Nope, CEL comes on whenever there is knock retard on any cylinder...

Yep, I just gave it some more timing last night and my CEL started to come on, but boy, it pulled hard before it did, :thumb:

moparzrule
03-10-2009, 09:54 PM
I owe a big thanks to Justin for tweaking my cal for better driveability. Before, my cal's (Thanks to Rob's base cal for even making it possible) were mostly for racing and/or limited street use. I couldn't figure out why or how to fix the chugging on cold startup, and I never seemed to get very good fuel mileage with them. I just did the R&D on ''max power'' and thats all I cared about at the time.
IMO justin's G head cal is PLENTY conservative for daily driver use, if you are running a G headed 2.5 you should not have to tweak anything except for perhaps fueling because everybodies setup demands different amounts of fuel. He knows how much more timing I had in my cal and I was running it with stock cast pistons. I never broke any 2.5 pistons from timing (only 1 time from a lean condition, bad FPR).

turbo84voyager
03-10-2009, 11:05 PM
I wanted to add a few things I learned about this cal and may help to fine tune this and or other cals.

Adjusting ColdStartFromCoolantTemp cleared up most if not all of the rich (black smoke) starting associated with many cals.

FuelColdEnrichA, B and C needed to be fine tuned when the weather got coolder. In the summer it was not as much of an issue, but in the winter my wideband would sit at 10.0 for almost my whole trip to work which was 8 miles. I ended up comparing it to a S60 cal I found and I used this as a base for these tables. I reduced the fuel quite a but and since then, in the winter it will start at about 11.5 and slowly climb to 14.5 after a few minutes. The dawes now looks like the dawes in my other cars with factory cals. It climbs to blue and after a few minutes drops and the red light occassionially flashes. This greatly improved fuel economy and the engine warms up much quicker. If this cal is too lean when it is cold you may have to add a little fuel to these tables. I have been running the van in sub zero temperatures with this cal and I did not have any problems.

There are 2 changes I still would like to make to this cal, I would like to richen it up a little when decelerating and I would like to lower the O2 Kicks. I believe this will lower the EGT's a little more. Currently cruising at 70 mph EGT's are about 1450. They will climb a little climbing a hill but as soon as I go into boost and it richens up a little they drop back to the low 1400's. Let me know if anyone knows how to lower the o2 kicks a little. Currently it jumps between 14.6 - 15.2 cruising.

I also want to try a cooler plug. I currently run RN9YC champions (autolite 63). The plugs have a tan color and don't have any salt or pepper spots. From looking at the plugs it looks like it can still use a cooler plug. I am going to see if I can get a RN7YC or a 62 plug. This plug appears to be obslete and no one local carries it. I am going to talk to the fram (autolite) rep and see if I can get some.

turbovanmanČ
03-10-2009, 11:13 PM
AFAIK, that cal doesn't have the Ox kicks that his new TSMEC's do.

moparzrule
03-11-2009, 06:32 AM
Justin there's nothing wrong at all with 1450 highway cruising EGT's, with spikes up to 1600. EGT's should be higher when not in WOT because you should be much leaner. At WOT a good A/F is 12:1, if it's that rich at cruise/part throttle you are just wasting gas.

ShelGame
03-11-2009, 08:02 AM
AFAIK, that cal doesn't have the Ox kicks that his new TSMEC's do.


Sure it does. They're just not ID'd in the table file. All cals have the O2 kicks/limits.

turbo84voyager
03-11-2009, 09:15 AM
Rob do you know where the kicks to adjust them?

ShelGame
03-11-2009, 10:38 AM
Rob do you know where the kicks to adjust them?

http://www.turbo-mopar.com/forums/showpost.php?p=452762&postcount=5

turbovanmanČ
03-11-2009, 01:25 PM
Sure it does. They're just not ID'd in the table file. All cals have the O2 kicks/limits.

That makes sense, I just never saw it in the older cals, :o