Honda tuner here, im lost tuning GM

PhilStubbs · Post by **PhilStubbs** » Fri Sep 10, 2010 4:09 pm

I have been tuning honda stuff for a few years now. im not new to tuning at all, but honda software seems quite a bit more straight forward.

i have a 1990 silverado with a tbi 350 and a 7747 ecm. the 350 is a crate engine that makes about 60hp more than a stock 350 so a tune is needed.

i loaded the $42 definition and the bin file. looking through tunerpro i dont really see anything i can make out for what i need. i am used to tables with rpm on one axis and manifold pressure on the other. is there a way to get fuel and spark tables like that?

Post by **robertisaar** » Fri Sep 10, 2010 5:09 pm

actually, that's exactly what you'll find, except instead of being in pressure, they'll be in vacuum since the $42 mask isn't set up for boost.

look for a VE table and it will make sense.

Post by **Mangus** » Fri Sep 10, 2010 5:10 pm

Sure. Look under "tables" and look for something that says "fuel table," "VE Table," or "spark table."

Pretty straightforward.

PhilStubbs · Post by **PhilStubbs** » Fri Sep 10, 2010 5:21 pm

thanks for the quick responses, i really didnt expect such quick help.

i found those after posting this. it only shows 3200 rpm though. is there something i am missing?

when i said intake pressure, i didnt really mean positive pressure. i figured there would be some extra effort to boost this engine. i plan to eventually, but for now i just need the truck for hauling some things and boost can wait.

also, is there a place to change injector size? i dont see the stock 55lb injectors flowing enough for the added hp

Post by **robertisaar** » Fri Sep 10, 2010 5:29 pm

a lot of the old C3 ECMs didn't have very large VE tables, and the way to deal with fueling above that is a combination of using the last value in the highest RPM in the VE table(and the correct MAP cell) and using the base(or adder VE, depending on how it was worded) VE table to add or subtract fuel.

injector sizes can be changed, you just have to look hard enough to find it. when the EGR isn't active, there is a constant to size injectors, and i assume there is a table for when the EGr is commanded on.

but i'm not an expert on TBI systems, let alone the early ones.

PhilStubbs · Post by **PhilStubbs** » Fri Sep 10, 2010 5:40 pm

can the rpm values be edited to go to redline, but have a larger gap between cells?

it kind of sounds like this ecm is a joke. maybe i need to consider converting to something else. lol.

Post by **robertisaar** » Fri Sep 10, 2010 5:42 pm

you have to remember what the $42 was built for: low-revving truck motors.

depending on what you're planning on doing, it probably is a good diea to swap to something more suitable.

PhilStubbs · Post by **PhilStubbs** » Fri Sep 10, 2010 5:56 pm

well, i dont have a ton of gm tbi knowledge, but i ASSumed they revved to 5k or so stock. i have no intentions of reving much over 5k, but my final goal is 350-400whp and 400ftlb with a holset hx40 spooling around 2500rpm. i didnt really expect the 7747 ecm to handle the task, but i figured i would push it as far as it would go and upgrade later. the main purpose of this truck is to tow my racecar so torque is important to me and thats about it.

do you have any TBI ecm suggestions? i know tpi would really be the way to go, but im trying to keep the cost down for now

Post by **robertisaar** » Fri Sep 10, 2010 6:01 pm

you can rev it to 5K easily.

the VE adder table goes up to 6400

spark advance also goes to 3600 and there is also pair of constants that add spark beyond that in the measures of how much and to how high of an RPM.

with boost, i would suggest going with any ECM that will run code59(the 1227730, 1227727, 1227749 and any derivatives of them), the 3BAR fuel and spark tables will DEFINITELY meet your needs and then some.

code59.org is a good place to read and ask questions about it.

i'm not sure how well code59 takes to TBI though... good question to ask on their forum!

PhilStubbs · Post by **PhilStubbs** » Sat Sep 11, 2010 3:12 am

cool, thanks for the info. my chip adapter should be here from moates today and im going to see if i can get the truck running a little better with what i have. then start upgrading as needed

i guess i went through the same amount of pulling my hair out when i first started tuning hondas years ago. it seemed like pulling teeth to get everything working and now i hook everything up and tune 300whp hondas in less than 2 hours. lol.

Six_Shooter · Post by **Six_Shooter** » Sat Sep 11, 2010 5:54 am

Tuning the '7747 ECM is one of my least favorite things to do, mostly because of the SLOW datalogging baud rate. 160 baud vs the newer ECM's 8192 baud.

The fuel tables are sorta split on these ECMs, GM also did the same on other ECMs as well. Probably has to do more with how the vehciles are used than for those of us that want huge VE tables. Most engines spend 99% of thier lives below about 3500 RPM, so focus effort on making the tables fit within the most commonly used range, in a 3D table. Then for anything above that, since the transitioning from one cell to the next would be so quick anyway a 2D "adder" table can be used. This 2D "adder" table will use the value in the highest RPM and pressure cell value, which would usually be 100 KPA and then change that value based on the adder table. It works pretty decently actually. It's just something to get used to.

Just wait until you look at stock boost code, such as $58. The VE table only goes to 100 KPa, with a boost adder table. The table still only goes to 4000 RPM, with no RPM adder table, just uses the last RPM value against the boost adder table. Two VE tables, one for open throttle, one for closed throttle....

As suggested, $59 would suit forced induction well, using a matching ECM, I don't think it's actually been used with TBI yet though, but there are settings in the ECM. I plan to do some bench testing eventually just to see if some of my theory is correct on getting it to work. FWIW, I use this code in my 1973 Datsun 240Z, that has an '81 or '82 280ZX engine that I have turbocharged and injected.

$59 has taken $58 to a whole new level. Extended VE and spark tables, with the VE table being extended to 300 KPa and 6400 RPM so a LOT more points have been added to the VE table, even though many of them will never get used, like the 300 KPA and 800 RPM cell. lol $59 also has the option of using two tables for open and closed throttle, or just the extended VE table (F29x). WBO2 ueling control among other enhancements.

The GM stuff isn't hard to figure out, there's just some small quirks you have to get used to, especially when using the stock code, and also realize that there are a lot of things in the code that you will likely never touch, but is defined in most XDFs just incase you think you might want to.

PhilStubbs · Post by **PhilStubbs** » Sat Sep 11, 2010 6:52 am

Awesome post. That helps a bunch. It does look like there is a bunch of stuff I will never touch. The Honda software is the same. I have a feeling getting in and using it will help.

On a side note, can these stock injectors handle more pressure than the stock 13psi? I have a walbro 255 pump I am thinking about putting in the truck to try to help overcome the small stock injectors.

PhilStubbs · Post by **PhilStubbs** » Sat Sep 11, 2010 12:08 pm

Ok, got the 24pin to 28pin chip adapter today. Soldered it in and tried tuning. When I turn the truck on the ses light just flashes. I thought it might have something to do with my ostrich so I burned a chip and it the same. It also does it with no chip installed and the truck runs exactly the same with or without the chip.

I opened the ECM up again and checked all of my soldering. Everything looks great(I probably have 40 chipped Honda ecu's under my belt without one problem) so I don't think that's my problem. I read something about a signal amplifier. Could that be my problem?

Six_Shooter · Post by **Six_Shooter** » Sun Sep 12, 2010 4:12 am

To use the Ostrich 2.0 with a '7747 ECM, or other Delco ECMs that use the 2732 PROM, you need the Socket Booster 1.0.

Did you solder a socket to the daughter board? I usually solder a socket to the daughter board, so that I can switch between the EPROM adaptor and the socket booster/Ostrich. I don't believe there would be a problem, using the Socket Booster and Ostrich plugged into the G1, but I haven't tuned that way.

Did you offset the bin to the end of the EPROM, when you programmed it?

PhilStubbs · Post by **PhilStubbs** » Sun Sep 12, 2010 9:39 am

I soldered a socket to the board, then plugged the adapter into the socket.

I checked the offset settings with something i found online but I don't remember the settings off the top of my head. Do you have any recommendations for offset settings?

Six_Shooter · Post by **Six_Shooter** » Sun Sep 12, 2010 10:27 am

Yep.

http://support.moates.net/2010/04/05/pr ... g-offsets/

You WILL need the Socket Booster 1.0 in order to use your Ostrich to tune the '7747. I have tried to tune without it, and only got very intermittant connection. Socket Booster 1.0 makes a solid connection. You do need the Ostrich plugged into a laptop though to power up the Ostrich, I always found that the Ostrich will not be powered up when not plugged into a laptop, when using the Socket Booster.

PhilStubbs · Post by **PhilStubbs** » Sun Sep 12, 2010 10:48 am

That's the page I used when I tried to burn the chip. I might try one more time. Have you ever needed the booster with a chip?

Six_Shooter · Post by **Six_Shooter** » Sun Sep 12, 2010 5:20 pm

PhilStubbs wrote:That's the page I used when I tried to burn the chip. I might try one more time. Have you ever needed the booster with a chip?

I haven't needed a booster with an EPROM, but I did find it seemed to work more consistantly with the booster. I EFI'd my boss' '62 Suburban, using a '7747, and sometimes, after programming a new EPROM, or rather a new file to the EPROM, I would need to cycle the key a couple of times before it would connect consistantly with my home made G2 adaptor. There hasn't been any mention of the CEL flashing so I would have to assume it's connecting perfectly everytime now. He would mention it if there was an issue.

You are installing the EEPROM with the #1 pin pointed towards the "inside" of the ECM, correct? That would be pointed towards the smaller CALPAK chip on the daughter board.

-=EDIT=- What programmer are you using?

PhilStubbs · Post by **PhilStubbs** » Mon Sep 13, 2010 2:08 am

Yes, the notch it pointing towards the smaller chip. I am using a burn 2 for programing.

I'm going to order the signal booster today. I hate burning chips to tune so I will need it for my ostrich anyway.

Six_Shooter · Post by **Six_Shooter** » Mon Sep 13, 2010 2:54 am

Using the Burn2 and Tuner Pro RT, the proper offset should be set automatically as you load the bin.

PhilStubbs · Post by **PhilStubbs** » Mon Sep 13, 2010 4:49 am

Yea, I remember not making any changes to match up to that moates page.

PhilStubbs · Post by **PhilStubbs** » Fri Sep 17, 2010 12:05 am

Well, I had some success. I got the truck running on the chip. I couldn't make it work with the ostrich even with the signal booster. Burning chips for every change has slowed the tuning process a lot since I don't have an aldl cable to log. I spent about an hour of tuning and made some major progress in making this truck run right. Hopefully I can get it really dialed in over the weekend.

Thanks to everyone in this thread for the help. I'm sure I am far from done with questions about this software. There is a lot to go through with it.

Six_Shooter · Post by **Six_Shooter** » Fri Sep 17, 2010 9:28 am

Get the ALDL cable, it will definatly cut down on the tuning time needed, especially when using the data tracing feature to know exactly what parts of the maps are being used.

What sorts of problems were you having with the signal booster?

Where were the switches set on both the Ostrich and the Socket Booster?

PhilStubbs · Post by **PhilStubbs** » Fri Sep 17, 2010 2:01 pm

Last I checked, moates was out of stock on them. I might check into the diy method. I planned to get one as soon as they were back in stock. I just really needed this truck driveable to finish moving some of my shop stuff from an old house.

I put the socket booster in set to 24 pin and the ostrich set to 28 pin. I kept getting the flashing ses light. Then I tried the socket booster on 28 pin and left the ostrich on 28 pin and got the same thing.

Map tracing would be awesome since I'm used to inhg and not kpa.