Mass Flo EFI anyone used or know how they are ?
09-13-2008, 12:35 AM
#1
Mass Flo EFI anyone used or know how they are ? Hi I have a World 454 sb and i want to put EFI on it . I know nothing about EFI I'm just looking for something that will give me good street manners, and easy instalation. It has a Dominator on it now .Its not in the car yet so I'm not sure how it will be for regular driving. I would like to keep the horse power close to the 600 it is now. Thank you for your time Wayne
02-25-2010, 07:29 PM
#2
Yeah i have the mass flo system on my 68 firebird 428 pontiac motor. I opted for the e-brock torker II with 30 lb/hr injectors as i have around 375hp. The system is straightforward to install and idles well and throttle response and closed loop operation and mileage are better than the carb.
However, the open loop operation was a different story. The way the chip was programmed as purchased, my air fuel ratio (AFR) at wot at high rpm was in the 15 range. Only found this out on my own after much back and forth with Chris R. Finally spent the money on the Zeitronix data logger and wideband O2 sensor. Then i had to purchase the Burn 1 F2A adapter to re-burn the chip, MYSELF. Minimal help from Chris. Essentially the system he sold me was probably burning my pistons until i solved the mixture issue. So in one aspect the system is plug and play as he says, so long as you never floor it.
After solving the AFR problem the car was still 30 to 40 hp shy of where it was with the carb. The GM 85mm MAF sensor is absolutley the culprit, (see my post on the "LPE 100mm MAF" thread pasted below). Its cross sectional area is 30% smaller than the throttle body that comes with the system. DO NOT let Chris R tell you are "barking up the wrong tree" when you bring up the 85mm GM bottleneck sensor, all the while you are wondering how you spent > $4000 and lost 8-10% of your horsepower.
Anyways, the data below is two years in the making. the 100mm MAF i used is not the LPE but the PowrMAX from
http://www.powrmax.com/PowrMAF%20100.html
(My feedback on the powermax is that it uses 12V to power it and not 5V like Bruce has on his website, 12V is what the GM 85mm MAF uses, otherwise the powermax works fine, AFTER calibration, it was about 30% off, but that could have resulted from my custom intake tubing setup)
Long story short, i got my horspower back with the 100mm MAF (actual ID is 102mm as advertised). If the conventional carb style air cleaner is a must for you then you'll be sacrificing.
Pasted from "LPE 100 mm MAF" in Gen IV external engine forum:
Here are results for an 85mm GM MAF compared to the 100mm ID MAF housing with a hitachi slot style MAF sensor (i.e. GM's newest MAF sensor).
Car/engine: 68 Firebird 428 ci engine convertied to multiport mass air EFI. E-brock torker II bung mod'd manifold, 30 lb/hr injectors, ~375hp.
The experiment is as follows. Airflow through the engine at wot and under full load is monitored by the output of the MAF and logged in real time along with engine RPM, with and without the 85mm MAF in place. The ECM is using the newly calibrated 100mm MAF as the MAF input signal in both cases. When the 85mm sensor in place it is in series with the 100mm MAF. To be clear, the 85mm is only being used as a restrictor plate, its wires are not connected to anything. Therefore we can trust the reading as they are from the same sensor in both cases.
The data below is converted into SCFM and is for a third gear pull at wot from 3k to 6k rpm WITH and WITHOUT the 85mm MAF in place. Each curve (data column here, don't know how to post images...) is an average of three runs (spread is tight run to run in each case). Same stretch of road, same day, time and ECT.
this a subset of the actual data, but shows the general trend:
with 85mm w/OUT 85mm MAF
RPM SCFM SCFM
3000 235 255
3500 290 295
4000 355 372
4500 410 446
5000 465 493
5500 495 540
6000 535 573
The 85mm MAF is a 7-8% flow constriction. Accelerometer and (rpm increase)/(unit time) data both support these data. I.e. the car is 8% slower with the 85mm MAF in place.
This translates to ~30 hp loss with the 85mm MAF bottleneck.
To get the full effect of the larger sensor, you need ALL your intake tubing to be 4" ID or larger as well as a high flowing air filter. To achieve this i made it all from scratch with fiberglass. Air filter is a 6.5" OD by 10" long K&N low restriction monster. I have pics, just give me ur email i'll send.
However, the open loop operation was a different story. The way the chip was programmed as purchased, my air fuel ratio (AFR) at wot at high rpm was in the 15 range. Only found this out on my own after much back and forth with Chris R. Finally spent the money on the Zeitronix data logger and wideband O2 sensor. Then i had to purchase the Burn 1 F2A adapter to re-burn the chip, MYSELF. Minimal help from Chris. Essentially the system he sold me was probably burning my pistons until i solved the mixture issue. So in one aspect the system is plug and play as he says, so long as you never floor it.
After solving the AFR problem the car was still 30 to 40 hp shy of where it was with the carb. The GM 85mm MAF sensor is absolutley the culprit, (see my post on the "LPE 100mm MAF" thread pasted below). Its cross sectional area is 30% smaller than the throttle body that comes with the system. DO NOT let Chris R tell you are "barking up the wrong tree" when you bring up the 85mm GM bottleneck sensor, all the while you are wondering how you spent > $4000 and lost 8-10% of your horsepower.
Anyways, the data below is two years in the making. the 100mm MAF i used is not the LPE but the PowrMAX from
http://www.powrmax.com/PowrMAF%20100.html
(My feedback on the powermax is that it uses 12V to power it and not 5V like Bruce has on his website, 12V is what the GM 85mm MAF uses, otherwise the powermax works fine, AFTER calibration, it was about 30% off, but that could have resulted from my custom intake tubing setup)
Long story short, i got my horspower back with the 100mm MAF (actual ID is 102mm as advertised). If the conventional carb style air cleaner is a must for you then you'll be sacrificing.
Pasted from "LPE 100 mm MAF" in Gen IV external engine forum:
Here are results for an 85mm GM MAF compared to the 100mm ID MAF housing with a hitachi slot style MAF sensor (i.e. GM's newest MAF sensor).
Car/engine: 68 Firebird 428 ci engine convertied to multiport mass air EFI. E-brock torker II bung mod'd manifold, 30 lb/hr injectors, ~375hp.
The experiment is as follows. Airflow through the engine at wot and under full load is monitored by the output of the MAF and logged in real time along with engine RPM, with and without the 85mm MAF in place. The ECM is using the newly calibrated 100mm MAF as the MAF input signal in both cases. When the 85mm sensor in place it is in series with the 100mm MAF. To be clear, the 85mm is only being used as a restrictor plate, its wires are not connected to anything. Therefore we can trust the reading as they are from the same sensor in both cases.
The data below is converted into SCFM and is for a third gear pull at wot from 3k to 6k rpm WITH and WITHOUT the 85mm MAF in place. Each curve (data column here, don't know how to post images...) is an average of three runs (spread is tight run to run in each case). Same stretch of road, same day, time and ECT.
this a subset of the actual data, but shows the general trend:
with 85mm w/OUT 85mm MAF
RPM SCFM SCFM
3000 235 255
3500 290 295
4000 355 372
4500 410 446
5000 465 493
5500 495 540
6000 535 573
The 85mm MAF is a 7-8% flow constriction. Accelerometer and (rpm increase)/(unit time) data both support these data. I.e. the car is 8% slower with the 85mm MAF in place.
This translates to ~30 hp loss with the 85mm MAF bottleneck.
To get the full effect of the larger sensor, you need ALL your intake tubing to be 4" ID or larger as well as a high flowing air filter. To achieve this i made it all from scratch with fiberglass. Air filter is a 6.5" OD by 10" long K&N low restriction monster. I have pics, just give me ur email i'll send.
