Running a 165 ECM along side a 7427 PCM

[Fast355]

Manufacturers are not utilizing computers to deliver the best fuel mileage possible. They are using them to meet the emissions requirements for the length of the federally mandated emissions law requirements and warranties of those systems. It really surprises me that a modern drive by wire vehicle goes full throttle at all now. 15-20 years ago the EPA was talking about closing the WOT emissons loophole thus OEMs would be using the drive by wire to decrease engine load to a point that the system would never use wide open throttle enrichment, thus always operating at a stoichiometric air/fuel ratio for cleaner emissions. I feel like modern controllers are calibrated first and foremost for emissions and warranty requirements, secondary to that for CAFE fuel economy, with drivability and power a distant third and fourth to the first two requirements.

[steveo]

'good enough'

that's the only reason one should use an antique ECM

or because you're poor like me, or like a challenge

if you desire real control, upgrade

the 1980s and early 1990s ecms were a dark era in fuel injection

tuning mid 90s and up ecms is a very different experience

im not saying you can't make the car just fine with this dual ecm plan, in fact its something i might do if i had the parts laying around, it's just that it's really not optimal for what you're doing and your goals

[tayto]

have you spent the last 20 years playing with your current ECU and tuning it? are you planning on tuning this yourself? do you have a datalog cable, chip burner, emulator, etc? you are setting yourself up for heartache/failure if you think your gonna tune this thing solo. thats why I mentioned an LS PCM on gmt400.com so you can at least get someone local to help tune.

[dave w]

This thread has some interesting information and debates.

I often wonder if the debate about which is easier to tune 1227165 (MAF) vs. 1227730 (Speed Density) is factor for wanting to use the 1227165?

Back in time, before TunerPro RT, the debate winner was for MAF. Fast forward to now, with Tuner Pro RT, the Speed Density is the clear winner of the 1227165 vs. 1227730 which is easier to tune debate.

The internet is filled with information about how MAF is easier to tune than Speed Density. It's interesting to point out, NONE of the MAF supporters mentioned or even referenced the tuning software used for tuning the MAF system.

[Fast355]

This thread has some interesting information and debates.

I often wonder if the debate about which is easier to tune 1227165 (MAF) vs. 1227730 (Speed Density) is factor for wanting to use the 1227165?

Back in time, before TunerPro RT, the debate winner was for MAF. Fast forward to now, with Tuner Pro RT, the Speed Density is the clear winner of the 1227165 vs. 1227730 which is easier to tune debate.

The internet is filled with information about how MAF is easier to tune than Speed Density. It's interesting to point out, NONE of the MAF supporters mentioned or even referenced the tuning software used for tuning the MAF system.

The 165 can run $12P MAP code as well but that is code developed off the Australian Holden 308 V8 application 808 ECM which shares its back bones so to speak with the 165. I find speed density much more accurate than those early MAF setups.

[steveo]

yeah definitely. keep in mind while GM was doing their early MAF systems, the Japanese were still using vane airflow meters in a lot of their cars. for their time they were very advanced. the history of fuel injection is a long and crazy one. participating in it on a running vehicle is like playing nintendo video games on a tube tv while the rest of the world has an xbox

[steveo]

.... of course i still play nintendo games and have never seen an x box. so if you want to play with old car computers, you are in good company. but lets not live a lie that some antique lean cruise routine is going to out-do a modern ECM somehow

[Fast355]

.... of course i still play nintendo games and have never seen an x box. so if you want to play with old car computers, you are in good company. but lets not live a lie that some antique lean cruise routine is going to out-do a modern ECM somehow

Agreed, especially considering the modern PCM also has an even better version of the lean cruise. With 8 coil packs there is more spark energy available to more effectively fire the leaner mixture as well. Could easily run 0.060" gapped plugs and have all the spark energy needed for that lower compression engine.

[Racprops]

Well, you've just arrived at the heart of the issue. The 165 was "good enough" even though vehicles with a more recent design were getting a better ecm. OEM choices are based on economy and profit. That's what business is. But you're in a different space.

Think of it this way... the 5.7 / 350 was "good enough" until the LS engine was introduced. But you're using a 383 instead. Why? And if you're using a better version of the factory engine what is stopping you from using a better version of the factory ecm? The 7427 has more features and more tunable tables. The LS pcm has more tables and features than the 7427 and it has a faster processor.

If you want to run dual pcm's, follow the instructions in the pdf previously posted.

I am subject to a lot of bad reports of engine failures with the newer engines and car, seem the newer they become the faster and more costly repairs.

Lots of reports of major problems with every transmission from the Ford 5R55s on up.

I know a SBC can take beating and keep on Ticking, and the same for a 4L80...and my Doug Nash Dual Range Overdrive. I CAN tow in the 4L80 in 3rd and in the DN Overdrive so I will be in 3rd overdrive.

With the newer many gears you really need to be in the 1:1 gear to tow.

So as my 93 G20 Van came with a SBC I want as close to a 400 I could get, so a383, and as I wanted torque a longer stroke gives that.

So what can a newer super PCM do better in my set up??

The 165 has a adjustable Highway mode, and it fades in and out automatically...need to pass something, just put your foot in it return to cruising speed and it fades back into highway mode. As I may not be the driver on long trips my co drivers need to not blow up my engine is we hit a hill, I NEED the system to be automatic.

I have seen some grade that snick up on you...and that might harm a manual lean burn.

So two questions how would one kick a system out of Closed Loop??

And what PDF?? the one where your running a carb and using the PCM as a TCM??

Rich

[Racprops]

Agreed, especially considering the modern PCM also has an even better version of the lean cruise. With 8 coil packs there is more spark energy available to more effectively fire the leaner mixture as well. Could easily run 0.060" gapped plugs and have all the spark energy needed for that lower compression engine.

Or I can add a MSD coil....or captaincy discharge system and do Multisparks for a longer duration.

The main advantage to all the newer stuff it it might last longer...and keep the smog better controlled, almost all these improvments ina STOCK car is to keep smog control, after all why the hell are not getting 40 to 70MPG??

Rich

[dave w]

Often the best plan for a project is low cost and simplicity. How much budget combined with technical skills. Often low cost and simplicity is a tug-of-war of compromises. OBD1 vs. OBD2 is a huge factor low cost and simplicity. If it was my 93 Custom Van I would likely keep the OBD1 EFI with some low cost modifications. There is a huge gap between planning a project and getting many miles of smiles. First comes the miles of smiles, then get more smiles per gallon.

94 Chevy C2500 5.7_4L80E_01.jpg

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[Racprops]

What I am doing is common, there a bunch of aftermarket Transmission controllers, all costing about 1K. SO many are doing them when running a non-stock transmission.

All I am doing it just using a 7427 AS a transmission controller.

Other wise it is just like doing a old style TPI swap into a different car or truck and I have a couple of manuals on how to do that.

I can see NO reason to run a OBDII and perhaps allow in gas wasting programing.

I truly believe the 86 to 89 SBC TPI was a special Intake system.

One that was dropped not because it did not work but for the very reasons I am so excited about them.

And one is that they make low end power or torque, which when the engine is tuned for it I believe will make great LOW RPM power which can make great MPG.

The TPI introduced performance fans to the merits of electronic fuel injection, it was TPI that launched the modern EFI performance era back in '85. Unlike previous carburetors (including the computer-controlled varieties), the TPI system offered precise metering of the fuel under all operating conditions.

Fuel efficiency and emissions were optimized by balancing fuel delivery to each individual cylinder. Unlike carbureted, TBI, and even the Cross-Fire EFI systems, TPI provided fuel injectors for each port, thereby balancing power production (and fuel usage) in each cylinder.

Even fuel delivery is difficult (if not impossible) in a typical carbureted (or TBI) application, so the air/fuel is tuned to the leanest cylinder. Unfortunately, this also means other cylinders run rich. This cylinder imbalance decreases power while increasing fuel consumption and exhaust emissions.

Designed to flow air (the injectors are positioned at the base of the intake to flow fuel only into the head port), control of just air (Called a DRY Manifold) allows the designers to move the air at its best ways without the dropping out of suspension of the fuel or puddling of fuel within the manifold."

This is always a problem with any manifold handling wet air, air and fuel together. And often means what is good for the air may not be good air and fuel.

The TPI systems incorporated tuned runner lengths to optimize power production at the lower rev ranges. With long, small-diameter intake ports, the TPI system enhanced low- and mid-range torque production.

To illustrate this point, torque production from a typical L98 Vette motor exceeded horsepower production by roughly 100 lbs-ft. Rated at 250 hp, the TPI system helped the 350 pump out an amazing 350 lbs-ft of torque.
This is done by a thing called Ram Air Injection, or even better Newton’s third law: A body (Or AIR) remains in motion at a constant speed until acted upon aother force. Air flow though the tubes want to keep flowing but the valves stop this even for a second and the air behind the valve PILES up and in fact make some positive pressure JUST waiting to get into the chamber.

It is RAMED Charged.

Naturally this overabundance of mid-range torque came with a penalty. The same runners in the TPI system that were designed to enhance power production below 5000 rpm, lost efficiency rapidly thereafter. TPI motors were all about instant gratification. There was never any waiting the cam to get in its power range of Come on, just plenty of torque to get things going in a hurry.

It is often forgotten that TORQUE is really what gets your car off the line, HP helps keep it moving.

Unfortunately, the long runner lengths quickly put an end to the party.

At lease for the High RPM HP people.

They say speed is what kills MPG and sure the faster you go the more gas you use. BUT is it truly the speed OR is it the RPMs of the engine??

My testing has shown low RPMs seems to be the best for MPG, this is a time proven fact, low gears, 2:73 always make better MPG on the highway over say a 4:11.

But the market in the automotive world is always for performance which is seen as higher HP and higher RPMs.

Those aims do not really make better MPG. They make speed.

But even Ford made their own versions of the Tune Port intakes for their 4.6 which I believe is why they make so much power out of a little 4.6 281 CI engine.

And before they retuned the 4.6 from 200HP to 240HP these engines could do 30MPG at 65MPH.

The jump to 240HP lost about 4 to 5 MPG reducing the MPG to 25/26. They did it by moving the power curve upward.

2000 Ford Crown Victoria
Horsepower 200 @ 4250 RPM Torque 275 @ 3000 RPM

Performance Improved w/dual exhaust option:
2003 Ford Crown Victoria
Horsepower 224 @ 4900 RPM Torque 272 @ 4100 RPM

SO 2000 30MPG with a Torque peak of 3000RPMs

2003 25/26MPG with a Torque peak of 4100RPMs.

Also like the SBC TPI The Ford version also is limited to around 5000RPMs.

Power takes Gasoline…

I have seen this all the time: More HP and Torque comes at a higher RPMs and means less MPG.
More vooom vooom….less MPG.

More:

I REALLY began to question the MPG on a road trip in the stock 93 TBI Van, around 2018 we took a trip to Sedona AZ which is near Flagstaff, Sedona is 4,350 feet above sea level, Phoenix is 1.086 feet above sea level. This is a serious climb, as I love to go fast I was keeping up with most of the highway traffic and doing 75/80MPH and a fair amount of that was at WOT and in Third gear.

The trip is 119.3 Miles and takes 2.2 hours.

I filled up before starting and filled up in Sedona and read the MPG: 14MPG.

I was OK that as it did not seem bad for hauling a big van up these mountains at 80MPH often is 3rd gear at full throttle.

We drove around a little, had lunch which include Rattle Snake, and hiked a nice trail. And drove back DOWN to Phoenix…

And I filled the tank at the same gas station and got WTF 14MPG!!!

Downhill and no change. 14MPG???!!!

OK Here is what I think, the car companies figured…everyone KNOWS trucks, vans and SUV have never gotten good MPG. Partly as I feel they were built to run a little rich just in case they are pulling a trailer or hauling a load.

Everyone KNOWS this.

So they (Car companies) can program the newer trucks PCMs to get those same historical MPG and no one will be the wiser…

So even if car with a new fuel injection system and an over drive can get 5 to 10 MPG just with those improvements, they program these Trucks, Vans and SUVs to get the same poor MPG and tell us IT’S A TRUCK. They are bricks you cannot get good MPG.

So one fix personally, I am planning on running a 87 Camaro 165 OBDI Computer was not as programed with this MPG killer program, and with these old ECMs they can easily be reprogrammed unlike the OBDIIs.

And these already are High Way Mode ready, which is better called Lean Burn Cruise, they just need to be turned on and programed for even better MPG than stock. I am going to run this on my 93 Van. Sadly, this cannot be done on hardly any other cars.

Lastly, IF the fact it is a van then it pushing through the air IS the main and ONLY fact then how did this van get 29MPG highway???


Rich

[Fast355]

What I am doing is common, there a bunch of aftermarket Transmission controllers, all costing about 1K. SO many are doing them when running a non-stock transmission.

All I am doing it just using a 7427 AS a transmission controller.

Other wise it is just like doing a old style TPI swap into a different car or truck and I have a couple of manuals on how to do that.

I can see NO reason to run a OBDII and perhaps allow in gas wasting programing.

I truly believe the 86 to 89 SBC TPI was a special Intake system.

One that was dropped not because it did not work but for the very reasons I am so excited about them.

And one is that they make low end power or torque, which when the engine is tuned for it I believe will make great LOW RPM power which can make great MPG.

The TPI introduced performance fans to the merits of electronic fuel injection, it was TPI that launched the modern EFI performance era back in '85. Unlike previous carburetors (including the computer-controlled varieties), the TPI system offered precise metering of the fuel under all operating conditions.

Fuel efficiency and emissions were optimized by balancing fuel delivery to each individual cylinder. Unlike carbureted, TBI, and even the Cross-Fire EFI systems, TPI provided fuel injectors for each port, thereby balancing power production (and fuel usage) in each cylinder.

Even fuel delivery is difficult (if not impossible) in a typical carbureted (or TBI) application, so the air/fuel is tuned to the leanest cylinder. Unfortunately, this also means other cylinders run rich. This cylinder imbalance decreases power while increasing fuel consumption and exhaust emissions.

Designed to flow air (the injectors are positioned at the base of the intake to flow fuel only into the head port), control of just air (Called a DRY Manifold) allows the designers to move the air at its best ways without the dropping out of suspension of the fuel or puddling of fuel within the manifold."

This is always a problem with any manifold handling wet air, air and fuel together. And often means what is good for the air may not be good air and fuel.

The TPI systems incorporated tuned runner lengths to optimize power production at the lower rev ranges. With long, small-diameter intake ports, the TPI system enhanced low- and mid-range torque production.

To illustrate this point, torque production from a typical L98 Vette motor exceeded horsepower production by roughly 100 lbs-ft. Rated at 250 hp, the TPI system helped the 350 pump out an amazing 350 lbs-ft of torque.
This is done by a thing called Ram Air Injection, or even better Newton’s third law: A body (Or AIR) remains in motion at a constant speed until acted upon aother force. Air flow though the tubes want to keep flowing but the valves stop this even for a second and the air behind the valve PILES up and in fact make some positive pressure JUST waiting to get into the chamber.

It is RAMED Charged.

Naturally this overabundance of mid-range torque came with a penalty. The same runners in the TPI system that were designed to enhance power production below 5000 rpm, lost efficiency rapidly thereafter. TPI motors were all about instant gratification. There was never any waiting the cam to get in its power range of Come on, just plenty of torque to get things going in a hurry.

It is often forgotten that TORQUE is really what gets your car off the line, HP helps keep it moving.

Unfortunately, the long runner lengths quickly put an end to the party.

At lease for the High RPM HP people.

They say speed is what kills MPG and sure the faster you go the more gas you use. BUT is it truly the speed OR is it the RPMs of the engine??

My testing has shown low RPMs seems to be the best for MPG, this is a time proven fact, low gears, 2:73 always make better MPG on the highway over say a 4:11.

But the market in the automotive world is always for performance which is seen as higher HP and higher RPMs.

Those aims do not really make better MPG. They make speed.

But even Ford made their own versions of the Tune Port intakes for their 4.6 which I believe is why they make so much power out of a little 4.6 281 CI engine.

And before they retuned the 4.6 from 200HP to 240HP these engines could do 30MPG at 65MPH.

The jump to 240HP lost about 4 to 5 MPG reducing the MPG to 25/26. They did it by moving the power curve upward.

2000 Ford Crown Victoria
Horsepower 200 @ 4250 RPM Torque 275 @ 3000 RPM

Performance Improved w/dual exhaust option:
2003 Ford Crown Victoria
Horsepower 224 @ 4900 RPM Torque 272 @ 4100 RPM

SO 2000 30MPG with a Torque peak of 3000RPMs

2003 25/26MPG with a Torque peak of 4100RPMs.

Also like the SBC TPI The Ford version also is limited to around 5000RPMs.

Power takes Gasoline…

I have seen this all the time: More HP and Torque comes at a higher RPMs and means less MPG.
More vooom vooom….less MPG.

More:

I REALLY began to question the MPG on a road trip in the stock 93 TBI Van, around 2018 we took a trip to Sedona AZ which is near Flagstaff, Sedona is 4,350 feet above sea level, Phoenix is 1.086 feet above sea level. This is a serious climb, as I love to go fast I was keeping up with most of the highway traffic and doing 75/80MPH and a fair amount of that was at WOT and in Third gear.

The trip is 119.3 Miles and takes 2.2 hours.

I filled up before starting and filled up in Sedona and read the MPG: 14MPG.

I was OK that as it did not seem bad for hauling a big van up these mountains at 80MPH often is 3rd gear at full throttle.

We drove around a little, had lunch which include Rattle Snake, and hiked a nice trail. And drove back DOWN to Phoenix…

And I filled the tank at the same gas station and got WTF 14MPG!!!

Downhill and no change. 14MPG???!!!

OK Here is what I think, the car companies figured…everyone KNOWS trucks, vans and SUV have never gotten good MPG. Partly as I feel they were built to run a little rich just in case they are pulling a trailer or hauling a load.

Everyone KNOWS this.

So they (Car companies) can program the newer trucks PCMs to get those same historical MPG and no one will be the wiser…

So even if car with a new fuel injection system and an over drive can get 5 to 10 MPG just with those improvements, they program these Trucks, Vans and SUVs to get the same poor MPG and tell us IT’S A TRUCK. They are bricks you cannot get good MPG.

So one fix personally, I am planning on running a 87 Camaro 165 OBDI Computer was not as programed with this MPG killer program, and with these old ECMs they can easily be reprogrammed unlike the OBDIIs.

And these already are High Way Mode ready, which is better called Lean Burn Cruise, they just need to be turned on and programed for even better MPG than stock. I am going to run this on my 93 Van. Sadly, this cannot be done on hardly any other cars.

Lastly, IF the fact it is a van then it pushing through the air IS the main and ONLY fact then how did this van get 29MPG highway???


Rich

Long story short those vans do not even come

close to those MPG figures in real world. The 4.3L is an underpowered slug. Throw in some wind, a few hills, a few passengers, a couple hundred lbs of cargo and that 29 mpg 4.3L struggles to get 18 mpg. OBD2 is easy to program and both the P01 and P59 had lean cruise from the factory that was very well implemented. With the coil near plug system you can also easily run 0.060" plug gaps with much longer spark duration than even a CDI system. The CNP coils with a wide gap are much more likely to fire and burn a lean mixture misfire free.

TPI was a fairly poor intake. The LT1 that replaced the L98 made more low-speed torque in the RPm range you are looking to run in. The L31 engines used in boats were cranking out 400 ft/lbs at 2,500 rpm and more than 350 ft/lbs @ 1,500 rpm. Some of them had MPFI dual plane manifolds while others had the L31 style crossram marine manifold. The TPi actually reduces torque in the rpm you are looking to cruise in. I have mentioned this multiple times to you over the years. Real world I had less low-speed torque with a TPI than I did with a dual plane and TBI as well as worse fuel mileage because the engine had to spin more rpm to make up fpr the torque loss.