The Stovebolt Site Forums The Shop Area Engine Shop TBI on a 1959 235

One thing I see that you may have changed since the pictures were taken is that the side cover is on inside out.
Good job though!

The pushrod cover?

Yes, the pushrod cover/engine side cover.
This is how it should be installed.

Huh, odd. It was the way I have it now when I tore the engine down. Well, other then looking strange it is sealed and doesn't leak so I will probably leave it for awhile. That's funny.

On a 1953-57 engine you would not be able to put it on wrong as the bulge out in the middle would not clear the oil tube under the side cover. Starting in 1958 they dropped the tube so it is possible to install it wrong.
Yours is not the first I've seen on wrong.

Thanks for the info. I will put it on the "to be completed list."

Anybody know what weight gear oil to put in the rear differential?

So it has been quite cold around here and I got the chance to see how it would start and run in the snow with the TBI setup. The truck fired right up, just as quickly as if it was warm outside and ran very well. However, it idles very high. I don't have a tac but it sounds like 1500-2000 rpms. Does this seem normal because of the cold weather?

And here is how it looks as of right now.

http://i1130.photobucket.com/albums/m537/kjhibbs99/Apache%20Rebuild/IMG_3417_zps30a4b3d8.jpg

Once it reaches operating temp does it idle down to the correct speed? Could be while cold the idle speed motor ( solenoid) may be told to open more than it needs. Depending on which computer you are using, you may be able to have tuner idle it down a bit during the warm up stage.

This is just one of many issues associated with trying to adapt an injection setup to run with a siamese head engine. Granted a setup like this is better in some ways on some engines over a carb, it is going to be impossible to get it "dead nuts" as far as tune goes compared to a non-siamese head engine.

[/quote]
This is just one of many issues associated with trying to adapt an injection setup to run with a siamese head engine. Granted a setup like this is better in some ways on some engines over a carb, it is going to be impossible to get it "dead nuts" as far as tune goes compared to a non-siamese head engine. [/quote]

Ok, "siamese head engine" is a new phrase for me, could you please explain it to me?

Honestly, Roy, I have not had it running long enough to get it to operating temperature. I will when I get a chance and see if it idles down a bit.

[/quote]

Ok, "siamese head engine" is a new phrase for me, could you please explain it to me? [/quote]

By design, these engines(Stovebolt, GMC Jimmy and 194-292 6 cylinders)are called siamese because they have one intake port that has to feed(2)cylinders. And for that reason and by this design, they have fuel sharing problems between those cylinder pairs that makes it problematic at best to try to use any form of fuel injection instead of a common plenum carb design setup. Fuel distribution between shared cylinders is impossible to achieve because of the cam timing between those cylinders also. It will be a never ending battle to tune and find a happy medium.

I'm not an expert on the fuel injection, but I might could see a problem if he were trying to use port injection. But with the TBI he is simply replacing the carb with another method to atomize the fuel. The droplets or vapor has to still travel the same path that carbureted (sp) fuel would have to take.

Since the TBI is basically dropping the fuel in much the same way a carb would I can't see why it shouldn't work as well as a carb would. Should work better if set up correctly.

Many times on a cold start the TBI units do idle up some while the engine warms and will settle down to the proper idle speed once the engine is warm. Much like an automatic choke on a carbureator. Also, even with the TBI set up it takes a few starts and drive cycles to allow the ecm to "learn" where the proper idle needs to be.

If he has the ALDL connector installed to hook a scanner up (not just a code reader) it would help to see what the data stream reads while the engine is warming up. Is the coolant temp sensor reading while cold about the same as the ambient temp? If he's getting a bad reading from it due to the sensor or wiring then that may account for some of the high idle.

It could be as simple as it needs to be ran long enough to actually warm up and perhaps driven a few times for the ecm to learn the new driving parameters.

Roy, I definitely appreciate the insight! Let me clarify, the thing runs great when the temp outside is warm. It idles smoothly, throttle response is quick, and it runs smoothly at speed as well. It is just idling high in this cold weather. I will borrow a scanner and see what I can find out.

This might help too.

http://www.73-87chevytrucks.com/techinfo/TroubleshootingTBISystems.pdf

Great resource! Thanks.

So what your saying is you start the engine and the fast idle on your choke is higher than you want it to be and stays on longer than you want it to stay on?
Is that correct?

Here's the big question, have you actually tuned the EFI system for your inline stovebolt or are you still running the factory GM V6 program that is designed to run in an async mode(technical term used for the injector firing mode on some GM EFI tunes) at idle.

Have you actually logged data and verified the fuel table is correct for your engine?
Have you changed the timing table so it is correct for your old stovebolt or are you running the factory late model V6 timing table? (You have probably seen them posted in the injection forum on the binderplanet)

If you haven't done all the above but you describe it as starts great and runs great, then I would say the old factory system is doing a pretty good job of adapting itself to your engine.

Have you checked for error codes with your SES-service engine light? Just jumper pin A and B of the ALDL connector and turn the key on.
Count the blinks.

Jumpering the terminals on the ALDL connector may not give any codes if none are there. He needs to have a scanner where he can see what is going on real time with his ecm.

I agree he may have a tuning issue, but could be the thing needs to ran for a while to get hot and make its adjustments.

If engine is off it will always give a code 12 indicating no DRP-distr ref pulse from the ignition module.
Laptop data log software is free and you can build a cable for about $6 with RS parts and then use a serial to USB adapter to connect to laptop or just buy a USB ready made cable for about $30.

Every system should be custom tuned to the engine/location for optimized performance and MPGs.
But the basic system will start and run just about any engine just like rolling of the assembly line. One size fit all.

The GM system can self correct for about 10% error in the fuel table as it is driven. normally about 50+ miles. The timing table will remain unchanged unless running a knock sensor, then it will retard the timing if ping is detected.
But you can bump the distr base timing to gain a little more or less depending on ping.

HTH

Glad I got on tonight. You guys saved me about 250 bucks buying a distributor for what I'm trying to put together. Will be converting my 1950 GMC 450 firetruck 270 engine to TBI using junkyard TBI parts. I will probably try and build my own intake. I already have Fenton Dual exhaust manifolds on the way. Love the "use what you got ingenuity" on here. Thanks for all the great info. Bill_USN_1, will the Pertronixs modules put out a proper trigger signal for the GM TBI ignition module. I'm currently running an Ignitor II in my stock distributor.Jim. Thanks again.

kjhibbs, where did you mount your knock sensor, if your using one? For that matter, where are all your sensors mounted? Any problems mounting in the block due to metric threads... on sensors? Thanks and the trucks looking great. Jim

Eagle,
The pertronics won't work.
Take a look at the injection forum on the binderplanet.
I hate having to send people away from here to see the info but I have been building it on there for about 12yrs covering a lot of oddball engines so it's a lot to retype each time!
If you go to the "start here" thread. It has links to each part of the system you will need. Or use a link in my sig. There's already a write up for the Stovebolt distr conversion for EFI.
The throttle body manifold adapter is also already available. I've even done a twin 1bbl setup for the dual carb intake.
BTW, the knock sensor is 1/4 pipe thread (NPT) not metric.

HTH

Thanks Bill. I did read your write ups on that forum. One of your post here left me thinking the Pertronixs would work. Maybe the way I read it. Your distributor conversion is going to save me the money I mentioned. Will start my own thread when I start my tear down. Thanks again. Jim

Jim,

Fantastic! I am glad this thread can help someone out. Here is a picture of my engine with the knock sensor. It is located on the bottom right towards the back.

Distributor conversion was a snap, and was way cheaper then buying anything ready made.

Bill, the quick answer to all of your questions is no. I haven't logged data, changed the programming, read live data, or any of that. I think I will get that USB cable from you on your website, though, that seems the best route for me to go in order to record some live data.

Alright, I finally got a good bit of data. I actually drove the truck to Pittsburg, Kansas and back. Its about an hour and a half one way. I went at about 55 mph, and the truck did well. Below is a link to my logged data. There is quite a bit there, Bill (and others), and I have been trying to compare it to what I believe is a standard set of data from Binderplanet. The biggest difference that would affect some of the other sensor readouts is that the standard data was from an engine running at 1000 rpms where as mine was at almost 3000 rpms.

I am not totally sure what each line means, but three things that stood out to me. My MAP reading seems high and inconsistent. My oxygen sensor readouts are erratic. And finally my lean / rich counter is all over the board.

Any thoughts?

https://www.dropbox.com/s/tvjtx6xjj56nasl/20140213_085731_LOG.xlsx

Kevin,
I looked over your data and noticed a couple things.
First it looks like you have not performed the initial setup procedures I have listed in the FAQs on BP.
Your TPS is way high and prevent the system from entering idle mode.
Also I recommend you review the data logging and basic tuning FAQs there.
You did good on the data log but should also have saved the BLM table.
I can tell that the fueling isn't too bad at idle(though your not in idle mode) but you go way rich while driving.
I recommend you also verify the inlet and return fuel pressure.
11-13 on inlet and 0 on return. They should not change even while driving. I run a T with a hose and stick the gauge under my wiper blade so I can watch it.

The system has to dither the fuel/O2 sensor from rich to lean in order to maintain the correct fueling, that means the rich/lean will bounce all over the place. Add to that the system has a slow sample rate so you are only getting a snap shot.

It also looks like your running the AKSB 4.3 chip.
Just from experience the factory GM 4.3 chips aren't the best for running an inline 6. It will run but has some characteristics that don't work very well.

HTH

Bill,

Thanks for getting back to me. I actually did do the initial setup procedures, at least as I understood them. I have not checked the fuel pressure, I will work towards that. Also, I did save the BLM table, here is the link to that (although I am not quite sure how to interpret it):

https://www.dropbox.com/s/bq8bdxvka2h31m3/20140213_103511_BLM.xlsx

Kevin,
The procedures have to be done in order.
It may be that once you got done you went back and turned up the MIN idle screw trying to adjust the idle speed.
That will also turn the TPS.
Keep in mind that the idle speed is controlled by the idle table in the ECM and not intended to be adjusted on the throttle body like a carb.
That screw is to be set to the minimum idle speed per the procedures.

The BLM data confirms the system is running rich.
if you review the "how to log data and what to do with it" FAQ, you will see that each cell goes from 0-256. The ecm is looking to adjust the fueling table to correct any number in that cell back to 128.
If the number s below 128 then the fueling is rich and the ecm removes fuel to get it back where it should be. The number you see represents how much the ecm had to adjust.
If it is more than about 10% away 128-12.8=115.2, then the system may not be able to correct.
if you look at the INT cells that will tell you. If they are 128 while the BLM is 115 then the ecm is correcting and the exhaust is clean.
So a number less than 128 means the tune is rich but does NOT mean the engine is running rich.

Bill,

That makes sense with the before you start procedures. I believe I did the adjustments and then readjusted the idle screw at the end. I will do those again.

As far as the "How to log data and what to do with it" FAQ, I had done many searches before and could only find this one:

http://www.binderplanet.com/forums/showthread.php?t=48653

is that the one you are referring to?

That's one of them.
This link is the main FAQ Page -frequently asked questions.
It starts with everything you need to perform a conversion and then I have a step by step install to include logging.
then I have a several write ups on the logging and tuning process towards the bottom.
There's about 12yrs worth of documentation there so lots to take in.
But other than buying a complete bolt on system from me ...it's about the best way to assure success.