TBI Tuning Issue

**BLG355** · 02-10-2014

Hello Everyone. I have long lurked this forum and recently decided to join and post. I have a 1995 K1500 5.7 Auto in which I just rebuilt the engine and transmission. I talked with a tuner before I built the engine to verify I would be able to have a good smooth running engine, and the guy said it would be easily tuned so I built. Here is what I built; it is 355ci with 2v flat top hypereutectic pistons (9.6:1). The block is zero decked for a nice tight quench of .038". It has Dart Iron Eagle S/S 165cc heads (72cc chamber) with the 87-95 intake face. I installed 1.94/1.50 valves. The cam is a Hydraulic roller cam, 204/209 duration @ .050" and it has .480/.496 lift w/ 1.6 rockers. It also has an Edelbrock 3704 TBI intake, Stock throttle body, stock injectors but with 18PSI fuel pressure per the tuner. I also have an upgraded fuel system to meet the demand of the high pressure and supply needs.

Now here comes the long part. I am on my 5th mail order chip and after sending 8 data logs, I am running no better than the first chip. I am hoping someone on here may have ran into this issue and has a quick fix, or can at least point me in the right direction. First thing I will point out is that the truck is 100% drivable with the stock chip and the base timing advanced 8 degrees. It obviously isn't anywhere near its full potential, but it is run and drives fine. With any of the five tuned chips I have tried so far, I have a nasty stutter/miss below 3,000 and a certain throttle percentage. If I put it to WOT, it runs awesome with all five chips, but pretty much anything below that it is so poor that it is almost not drivable. It misses so bad, it feels like it is dropping multiple cylinders or something. It feels worse than if I were to switch two of the plug wires. And it's more than just a miss. It has almost no power when it is doing it. I can pull out from a stop sign and give it 20% throttle and it will buck and kick all the way up to 55mph until I finally get out of the throttle, and it gets there slowly. It doesn't matter what gear or whether the engine is cold or warm. it will do it constantly while driving. But I can pop the stock chip in, advance the base timing a little, and it accelerates smooth. No issue at all.

The tuner claimed it was bad spark plugs, then a coil, and now saying it could be my heads...which I am almost regretting even doing this now because I've been building and racing engines for 15 years and never had a set of heads that were good cause problems with and engine. It almost seems like he doesn't want anything to do with it and I have been dealing with him since December and he is extremely hard to get in touch with. He won't answer calls and just plain doesn't respond to the emails, another new chip just shows up in the mail after I send on back and let him know what is going on. I may end up learning to burn my own chip but not until I get this thing at least decent from the guy considering he already got $270 from me. I am going to attach some data logs I made in TTS Datamaster 0D. Runs 4 and 5 are chip 3, runs 6 and 7 are chip 4, run 8 is chip 5, and run 9 is chip 5 with new coil and oxygen sensor. Run 10 is the stock chip with base timing advanced 10 degrees. If anyone would have time and be interested in looking at these, I would be greatly appreciative. I would love to hear what you think and any possible resolutions you may have. If you think the engine combo sucks and I am asking too much and it can't be tuned let me know that too. I was under the impression that it is totally tunable, but that is just an opinion. Any feedback with be a huge help, thanks in advance.

Barry

P.S. I having been messing with and building engines my whole life, but I am very new to anything with fuel injection to this magnitude and I am learning a lot as I go. The last thing I want to do is throw a carb on it, which to me is so much easier but I would like to keep the fuel injection so I am here looking for help. Thanks.

**EagleMark** · 02-10-2014

I'm looking at your data files now.

It's a shame a stock chip with adding timing works better then a custom retuned 5 times chip! Kind of proves it's not your engine but the tuner...

You could do what all the others in your same situation do and ask for a refund! But that does not seem to work with him... TBI Chips.com right? Then when you file a complaint with CC company it's been to long... sorry, this is what others have gone through.

Then hire me to make your engine run right. Look around the forum and you'll find all the one's I and others have fixed. There is nothing wrong with your engine or heads. It's the tune and is a normal occurrence with this tuner, been going on for years and he's still not figured out how to fix it!

First the issues your experiencing can't be found on DataMaster. It took me a long time to learn DataMaster since I use TunerPro RT to find out why!

Sorry, but there's plenty of threads on many different forums warning of this but it seems people don't do the research to find a tuner capable or incapable and since he does SO MUCH advertising he get's the work first.

**EagleMark** · 02-10-2014

What is your actual fuel pressure? Some people think just because they bought an 18 PSI spring it's 18 PSI.

Your log 9 fueling is close, still pig rich on decel. Spark advance is not even close to what it should be at idle and low RPM, after that it's OK.

EGR still hooked up?

Error code 42 is on but that always needs to be cleared after setting timing. Timing is working just fine.

**BLG355** · 02-10-2014

It is TBIChips.com. I heard bad and good about him. I figured since this is an extremely mild engine(in comparison to what I am used to playing with) that it wouldn't be hard to tune and he really talked himself up. I actually have a shim in the fuel regulator to get 18 psi. I have a gauge inline to check it. without the shim I am getting 15psi. at first we had 80lb injectors running at 15psi and the plugs went black within a few miles of running. The first time around he told me one of the 80lb injectors was bad and I got another under warranty but the issue was exactly the same. Then we tried running stock injectors, I assume they are 55lb, they are orange and black on the top, at 15 psi, which didn't work. then we shimmed the spring to get it to 18 psi, which didn't work. The code 42 was because I didn't clear it after setting timing. I also told him several times to remove the EGR since in PA I am exempt because it is under 5,000 miles but it was still coming up. I have found he can be rude and doesn't always know what he is talking about. I really do not like to say that about anyone at all, especially since he can actually burn a chip and I can't(well maybe not right but he has the physical ability), I am in no place to judge...but I know it has been too long for a refund and I am looking elsewhere. What's really annoying is that I was originally going to use TBI heads be cause I wasn't worried about high rpm at all and he talked me into the dart heads and now he is saying they are the problem.

**EagleMark** · 02-10-2014

The stock 5.7L injectors are 61 lb/hr and with your cam and RPM should be OK at 16 PSI on my calculator. Which is about the same as the 80 lb/hr at 12-13 stock pressure.

Well EGR is still on in ECM, is it still on the engine? The ECM makes fueling and spark changes when EGR comes on whether it's there or not.

Sorry your in this position! I'd rather get the work first then have to deal with people who have to go through this, would be much easier and cheaper... just look around here or ask if you need references.

**BLG355** · 02-10-2014

the EGR is still there, I have a tranny check ball in the vacuum line to keep it from opening. I am going to install a plate between the valve and intake once we get a break from the ice and snow. I was considering trying to do my own chip but if you want to tackle it, PM me or I can PM you and we can get the process started.

Thanks,

Barry

**brian617** · 02-10-2014

I'm running an very similar set up. It can be tuned, and you've come to the right place. These guys can help you sort things out, but I would recommend getting the hardware to burn the chips yourself. I'd be glad to post my .bin if you get to the point of tuning it yourself.

**Roadknee** · 02-10-2014

Brian - I'd like a look at your bin to help with my learning curve. I'm running the 427 PCM. Thanks!

**1BadAction** · 02-10-2014

If the EGR is disabled mechanically, it needs to be disabled in the tune also. There are spark adders and fuel modifiers active when the EGR is supposed to be active that will cause detonation if the EGR is not working.

Mark will get you sorted, I bet you'll be happy with the end result.

**EagleMark** · 02-10-2014

I sent you a PM Barry, what ever you decide, we are a tuners website so with time and reading you can understand and catch up to terminology and ask good questions.

**lionelhutz** · 02-10-2014

You described a nice engine build with decent power upgrades which should be easy to tune. I find it hard to believe the tune could be missed so badly that it won't even run right. The re-tunes must simply be broken if it'll run on the stock tune half decently. I'm a hack tuner and tuning that engine wouldn't worry me at all.

I would say download Tunerpro RT and set it up to do some logging instead of TTS.

**brian617** · 02-11-2014

Originally Posted by Roadknee

Brian - I'd like a look at your bin to help with my learning curve. I'm running the 427 PCM. Thanks!

My .bin is a mixture of BDHC and BJDR with heavily moddified VE tables and a moddified spark map based off a Vortec engine.

**BLG355** · 02-11-2014

Originally Posted by lionelhutz

You described a nice engine build with decent power upgrades which should be easy to tune. I find it hard to believe the tune could be missed so badly that it won't even run right. The re-tunes must simply be broken if it'll run on the stock tune half decently. I'm a hack tuner and tuning that engine wouldn't worry me at all.

I would say download Tunerpro RT and set it up to do some logging instead of TTS.

I spent a lot of time seeing what other guys were running before I built this engine. The only thing I was never able to find was anyone running an Isky Cam, which I use in pretty much everything I build, but other than that I tried to get close to some other peoples builds that had successful tunes, even TBIChips has a build close to this on the website, and he claims he had no issues with it. I did download TunerPro RT, I am going to see if I can do some logging and see from there which way to go. I used a Eagle Crank, Scat H beam rods, full floating pistons. I had the assembly balanced and I figured a worst case scenario is that I would put a stock GM replacement engine in and build this engine up since it has a solid bottom end and put it in a new toy or build another race car or something like that.

I have read other places that some of the chips they received from TBIChips were the same and previous ones, I am really not surprised considering all the bad I have read about him, but I really was just hoping for the best.

**Fast355** · 02-11-2014

Originally Posted by BLG355

I spent a lot of time seeing what other guys were running before I built this engine. The only thing I was never able to find was anyone running an Isky Cam, which I use in pretty much everything I build, but other than that I tried to get close to some other peoples builds that had successful tunes, even TBIChips has a build close to this on the website, and he claims he had no issues with it. I did download TunerPro RT, I am going to see if I can do some logging and see from there which way to go. I used a Eagle Crank, Scat H beam rods, full floating pistons. I had the assembly balanced and I figured a worst case scenario is that I would put a stock GM replacement engine in and build this engine up since it has a solid bottom end and put it in a new toy or build another race car or something like that.

I have read other places that some of the chips they received from TBIChips were the same and previous ones, I am really not surprised considering all the bad I have read about him, but I really was just hoping for the best.

Sounds like his tunes get worse and worse as time goes on.

I have seen his timing map for a vortec head 350 chip and it was STOCK TBI like in every way.

I can promise that setup is going to want more timing across the board seeing it is around 9:1 and has substantially less DCR than stock. Also lacks the swirl ramps fasy burn properties.

80 lb/hr injectors should have been no issue had he know what he is doing. 18 psi should give a little extra room as far as fueling goes to keep the duty cycle down as the tach swings toward redline.

I had a reed grind cam in my TBI and ran a victor jr 2bbl single plane, marine 502 TBI ( high pressure 61# injectors @ 30 psi), and vortecs with 2.05/1.60 valves and ~260 cfm intake/200cfm exhaust @ .500. I was putting down ~370 rwhp and had near stock driveability and tons of torque. You just have a tuner that has no idea and does things like setting bad BLM limits to mask a poor tune!

**Nasty-Z** · 02-11-2014

Originally Posted by BLG355

It is TBIChips.com. I heard bad and good about him. I figured since this is an extremely mild engine(in comparison to what I am used to playing with) that it wouldn't be hard to tune and he really talked himself up. I actually have a shim in the fuel regulator to get 18 psi. I have a gauge inline to check it. without the shim I am getting 15psi. at first we had 80lb injectors running at 15psi and the plugs went black within a few miles of running. The first time around he told me one of the 80lb injectors was bad and I got another under warranty but the issue was exactly the same. Then we tried running stock injectors, I assume they are 55lb, they are orange and black on the top, at 15 psi, which didn't work. then we shimmed the spring to get it to 18 psi, which didn't work. The code 42 was because I didn't clear it after setting timing. I also told him several times to remove the EGR since in PA I am exempt because it is under 5,000 miles but it was still coming up. I have found he can be rude and doesn't always know what he is talking about. I really do not like to say that about anyone at all, especially since he can actually burn a chip and I can't(well maybe not right but he has the physical ability), I am in no place to judge...but I know it has been too long for a refund and I am looking elsewhere. What's really annoying is that I was originally going to use TBI heads be cause I wasn't worried about high rpm at all and he talked me into the dart heads and now he is saying they are the problem.

Barry ,

Where in PA are you ? I am in the Eastern part , near the Poconos.

TOM