So, I am going to do some mods on a 1987 Corvette L98 engine, and don't want to fight with the factory computer, even though I will be retaining the TPI. From what I understand, the guy that made the GM system tunable passed away anyway, right?? "Emulator"??

So what is an affordable, tuneable system to run the factory TPI? FITech? Megasquirt?

Then I guess I am forced (finally) to learn how to tune EFI. What's a cheap, yet beginner friendly way to go here? The mods I'm thinking of pretty much take it out of "chipping it", and I truly hate the idea of chips in any case...

Help??

Thanks,
Vettepilot

 

It's actually a very tunable system. It;s not that difficult to flash proms and run an emulater for "live" tuning. If you don't care for the MAF then not the ard to repin to a 730 ecm that's MAP. Or you can go aftermarket=there's a few choices. Either way you have to learn the basics of tuning.

 

There are a lot of opinions on this topic. But I think most people would agree the easiest ECU to learn on is a Holley. I've had a Holley Terminator in my car for a while now. They get you running out of the box. The fine tuning and adding extra features takes a little time to learn. But being the Holley ECU's are so popular there are hundreds of YouTube videos that show how to tune. Because of this I say it's my top pick even though it is more expensive than other options. You don't have to spend the money on a Dominator ECU either. Holley has a lot of different models with very different prices. So read the specs carefully and pick the one that has the features you need.

My ECU with a new harness for the engine and transmission was $1200 a few years ago. But this let me LS swap and start with a 4l60e. Then it let me swap to a 4l80e a year later. And at that price came with a touch screen that can be configured for all kinds of stuff. Now I have it controlling my nitrous.

 

I tend to agree that the Holley is the most user-friendly entry level aftermarket ECU.

 

Yeah, if the TerminatorX can drive the injectors and use the sensors, it is the most future proof piece of hardware. If my wiring was decent in my car, I would have gone this route because my end game is LQ4 and 4L80E. And, you can get froggy and if you decide to plop in a Gen 3 Hemi, it will run it. Coyote? Same.

The only advantage of the Dominator is all the extra inputs and outputs available.

 

I just bought the Holley HP L98 kit for my 1989 396 Six speed car. I haven't installed yet but have done other Holley's on a few Foxbody mustangs. For the corvette I think the biggest questions I see is how to wire into the factory fuel pump system and the cooling fans. I will be doing a full write up on my installation in the coming weeks.

 

Please put a link to your install thread here in this thread.

Thanks!

Otherwise... I see a Megasquirt 1 kit can be had for under 200 bucks. What are the downsides to Megasquirt 1? Keep in mind I will NEVER need functions for Nitrous, Boost, Multiple Stage Breakfast Preparation, etc. I just want to run a simple L98 that has been modified past what the stock computer will do without chipping it.

Chips are a dead art that I don't want to get in to. I understand that something was made to make the stock system tuneable, was it called "Emulator"? You sent your computer to a guy and he modded it to be tuneable. But I hear he died...

Vettepilot

 

There is nothing wrong with Megasquirt. They aren't nearly as user friendly but they work well. The last time I checked if you have an auto you would need two devices from them as their ECU's can't lock up a converter or control an electronic transmission. That may have changed though. There are some two injector output Megasquirt ECU's that are in that $200-300 range. But for a TPI I would think you would probably want to go with the MS3Pro mini at least. They are around $600 just for the ECU. Then like I said before I think you would need to spend more to get transmission control. The downside here is the learning curve is much sharper. You also don't have the online support like you do with Holley.

With Holley if you get miserably stuck and need help there are pro tuners who you can pay to remote into your laptop that is plugged into the car. And as long as it's within WIFI range they can write a tune for you. Then you drive the car. If you have tethering on your phone with a WIFI hotspot they can continue to tune while you drive. Or if you don't then you just email them a copy of a data log from your test drive and let them remote back in to make adjustments. I don't think you can get that kind of support from any other brand. I never had go with a pro. After taking some online Holley tuning classes I figured it out on my own.

 

I keep hearing that the customer support is much better from Haltech than from Holley. Their Rebel LS is priced to compete with the Terminator, but I don't think that includes the display, so you'd have to hope it will work with what you have now (pretty sure it would, because I think the digital dash takes mostly standard inputs that any decent ECU would have no trouble generating, but don't quote me on that). I don't know what kind of extra hardware you have to install, if any, to make the Terminator work, so that's possibly another drawback for the Haltech.

And one other thing about being able to "tune it yourself", I'm convinced this is an illusion. Every expert I've heard from says that you really can't properly tune without a dyno. The mixture control is pretty much automatic, and there's not much to be gained there anyway—the main benefit of tuning is spark timing, and there's no safe way to do that except on a dyno. If someone "tunes" your car remotely, or if you use a pre-packaged tune, you're not getting anything more than an educated guess at how much advance it should have in any given set of conditions.

 

I can't speak to Haltech customer service. But I felt that Holly's support was very good. I had issues with my IAC when I first got mine and they bent over backwards helping me figure out the problem. They offered tuning advice and got me through the problem that's for sure.

You're right about timing being an educated guess. But tuners have a lot of data out there to make a very good educated guess. There are thousands of tunes from dyno tuned cars available online. All a tuner has to do for the average customer is find a tune that is close. Reduce timing by a few percent and try it. This isn't as close as a dyno tunes will get you. But it's pretty good. Of course you can do this yourself. I learned this in one of the Holley classes. But this is an issue with any tuning not just aftermarket ECU's.

 

Agreed... 7730 ECM + Ostrich emulator and Tunerpro and you're pretty much 21st century level of tuning. Granted the hardware itself has obvious limitations due to being designed back in the 1990's..(i.e., no sequential injection, single O2 sensor on one side of the engine, no self-learning, etc), but the tuning of it is very easy.

Pull over to the side of the road, make a change, upload to Ostrich (without even shutting the engine off), and keep driving...

And with the upgraded S_AUJP code, you can get the ECM to see a WB O2 sensor and report it out to Tunerpro for datalogging, which you can install on the other side of the engine for visibility on both sides.

 

I would avoid MS1. It works fine, but its fairly clunky. A microsquirt is based on MS2 and is very good bang for the buck. I used one on my C4 for a couple of years before upgrading. The only downside being batch fire, but depending on the conditions, you'll never know the difference.

 

I ended up with a Megasquirt MS3 + Expander a few years ago.
I used the original ECU until the end but tuning changed to a whole new level after installing Megasquirt.

I ended up with Megasquirt because it has extensive features, a reasonable price and my mechanic had it in use.
Then I just learned how to tune it with the help of friends and the internet and I've been happy with it.

My mechanic made a wiring harness that I used to connect the car to Megasquirt and I can always connect the original ECU back to the car if I want.

 

FiTech has systems specifically for standalone TPI. Around 850 for basic, and a grand for the unit that will also run the trans.

Any thoughts on their systems? It looks like the Holley systems are more like 2000!

Vettepilot

 

I don’t know much about the system, but it’s caught my attention and am also eager to hear from someone who has info on the system.

 

My Holley system with trans control, touch screen and harness was $1200. But that was a few years ago.


I just looked it up. So if you wanted to keep the factory 700r4 then a Holley Terminator X would work. They are $1280 MSRP. This has I/O that can be configured to operate the lockup converter. You only need transmission control on an ECU (Terminator X Max) if you are swapping to a 4L60e or 4L80e. Also this price is for a kit with the harness and the touch screen. If you call Holley directly they also sell a kit that in place of the touch screen, comes with a data cable for a laptop. These kits are usually around $200 less. So you could get a Holley Terminator kit with a harness to run a TPI for around $1100 MSRP. That includes the wide band O2. Yes this is a bit more that an MS3Pro. But given the ease of tuning and how good the online support is it's something to think about. Also this is MSRP. You might be able to find a better deal somewhere.

https://www.holley.com/products/fuel.../parts/550-936

 

Thanks for all the input guys.

You see, what I am doing is putting a 454 in my 1987 Z-51 four speed Vette. The left over 350 TPI, with some good heads and a small cam would be a super great, torque strong engine for my 1994 K-1500 4x4 half ton pickup.

The truck has a 4L60E, but I figured I would just piggy back the OEM computer to run the trans only, then have whatever aftermarket system I go with control fuel and spark. However, if I got a system that could run the trans too, that would be cool as the stock setup has really goofy, very early shift points. (Smog and mileage settings.)

One further possibility yet would be to just use the Corvette computer. I would be pissing off the stock, Corvette ECU by adding AFR Enforcer heads or something similar, and a cam. The cam won't be very big, as a big cam is not a good match for TPI, nor my intended use. The cam will have a tight lobe center however, which EFI systems find difficult I am told.

Guys, I am 70 and quite knowledgeable and experienced. I built race cars, boats, motorcycles, and experimental airplanes. I just switched careers about the time EFI really got going, and I never got into tuning a hotrod EFI setup. At 70 years old now, I'm very tired and don't want to dig in and learn raw EFI tuning from scratch. I could recognize that I need to "richen up the "accelerator pump" shot", or see that I need to "fatten up the mid range", or dozens of other tuning scenarios, and I know how to click a mouse, but other than that---> I don't know a "bin" from a "adx" file. All this is what keeps me from buying Micro or Megasqirt right this moment.

I only need fuel and spark control. I don't even want the computer turning the fans on, and certainly don't want multi-stage nitrous, nor breakfast in bed. Just a super simple system, but with a "For Dummies" interface and a cheap price...

I hope I don't get frustrated enough to buy a carburetor for this rig...

:~(

Thanks again,

Vettepilot

 

Well there is one issue. The easier an ECU is to the tune the higher the price. The Holley will run the motor out of the box and with the touch screen will run without a laptop at all. But you pay for that convenience. A higher end Megasquirt can do anything a Holley can. But they aren't as user friendly.

Something to consider is places like this. For example: I'm no pro. But I can tune with Holley EFI well enough that I could set up a tune for something naturally aspirated and get it running pretty well. I know there are guys here with experience with Megasquirt and other brands. If you get stuck just ask for help. I would be more than happy to email your tune file back and forth a few times till we got something you were happy with. People here have helped me with all kinds of stuff over the years. That's what forums like this are for. I'm sure others would help too. We might not always agree and sometimes bicker like old women. But most people here are willing to help.

 

I am in the process of installing the FiTech in my 86. It is not finished yet but has been very straightforward to install, the lengthy part of my project is removing all of the factory wiring harness that will no longer be needed to make for a neat install. You can download the instruction manual from FiTech so you can look at everything before you buy but for putting a stock L98 in your truck and controlling the trans I think its perfect. Edit, I see you may do cam and heads which it my reasoning for the FiTech, heads, cam and intake base/runners.

 

I would be inclined to keep the 87 (165) ecm just for the 4+3 overdrive control, but that's me.