Opinions from the fuel/ecu wizards, please....
09-18-02, 12:29 AM
#1
Lexus Test Driver
Thread Starter
Opinions from the fuel/ecu wizards, please....
Im looking for some ECU/Fuel ideas on an SC300 NA-T.
This solution has to support around 650-750rwhp. (somewhere in the T72, Greddy T78, SP70 size range)
Here is what I have:
Fuel Injection:
6 Sound Performance balanced 750cc injectors (originally on Dave Stika's car). Sound Performance bored out N/A fuel rail with two feeds and center return.
ECU: stock NA
Fuel Supply:
Will probably use dual walbros, or dual TT pumps and dual lines with an aeromotive FPR haning off the back of the center return.
Questions:
1. Should I go with an AEM ECU and fumble through the endless tuning, or should I just do a VPC/SAFC?
2. Will an NA ECU with VPC and Apexi SAFC control the SP 750cc low impedance injectors? I thought the stock ECU would only do high impedance.
3. I understand that a VPC and SAFC are easy to setup, fairly easy to wire and require a lot less setup time. But, by the time you add up the VPC SAFC GFORCE, you're significantly above the AEM ECU.
If I go VPC, I NEED to have Gforce mod my ECU to raise the rev limit to take advantage of all the porting, head work and big cams that are installed.
Any and all ideas would be appreciated. Think out loud with me here.
BTW....I'll have a stock NA fuel rail and stock injectors for sale soon if anyone is interested. The injectors are higher mileage, but the plugs always looked identical, so the flow rates should be fairly balanced.
If anyone has anything related for sale that I may be interested in, let me know.
This solution has to support around 650-750rwhp. (somewhere in the T72, Greddy T78, SP70 size range)
Here is what I have:
Fuel Injection:
6 Sound Performance balanced 750cc injectors (originally on Dave Stika's car). Sound Performance bored out N/A fuel rail with two feeds and center return.
ECU: stock NA
Fuel Supply:
Will probably use dual walbros, or dual TT pumps and dual lines with an aeromotive FPR haning off the back of the center return.
Questions:
1. Should I go with an AEM ECU and fumble through the endless tuning, or should I just do a VPC/SAFC?
2. Will an NA ECU with VPC and Apexi SAFC control the SP 750cc low impedance injectors? I thought the stock ECU would only do high impedance.
3. I understand that a VPC and SAFC are easy to setup, fairly easy to wire and require a lot less setup time. But, by the time you add up the VPC SAFC GFORCE, you're significantly above the AEM ECU.
If I go VPC, I NEED to have Gforce mod my ECU to raise the rev limit to take advantage of all the porting, head work and big cams that are installed.
Any and all ideas would be appreciated. Think out loud with me here.
BTW....I'll have a stock NA fuel rail and stock injectors for sale soon if anyone is interested. The injectors are higher mileage, but the plugs always looked identical, so the flow rates should be fairly balanced.
If anyone has anything related for sale that I may be interested in, let me know.
09-18-02, 01:33 AM
#2
Lexus Champion
Well, let's be honest Scott, are you going to find yourself a year down the road, wishing you had just went with the AEM and spent some time tuning? Probably. Simplest way I can think of it is, longer to set up and tune because there's more you can do, and everyone seems to be migrating to the AEM lately, though I haven't personally seen any dyno sheets from AEM users that dropped my jaws, but i'm sure it's only a matter of time. Dyno sessions are pretty reasonable after all, I say go for it. Now let's wait to hear from all the armchair dyno experts who'll probably chime in on this.......
- Jon
- Jon
09-18-02, 11:03 AM
#3
Lexus Test Driver
Thread Starter
I've heard alot of mixed things about the AEM... too complicated, hard to setup, easy to make a mistake on a fuel map, etc. But I've heard that it can also do so many things that would take five other boxes to accomplish. People also say that it has more stuff on it than the Speed Pro, although everyone that uses the Speed Pro raves about how easy it is to set the fuel maps, Plug in your desired A/F ratio, see how the unit corrects the map in the table, and go from there.
Chris @ Horsepower Freaks made a little boo boo and ran a Map sensor that didn't extend far enough to map his high boost. As a result, the AEM didn't have a fuel table for it, boost ran right off the map and melted a bunch of pistons - shortblock ruined.
But perhaps the AEM really is near ideal, and the safe way would be to just start out with the boost very low, and creep up gradually.
Any ideas?
Chris @ Horsepower Freaks made a little boo boo and ran a Map sensor that didn't extend far enough to map his high boost. As a result, the AEM didn't have a fuel table for it, boost ran right off the map and melted a bunch of pistons - shortblock ruined.
But perhaps the AEM really is near ideal, and the safe way would be to just start out with the boost very low, and creep up gradually.
Any ideas?
Last edited by SC300T; 09-18-02 at 11:03 AM.
09-19-02, 11:02 PM
#4
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Though I have limited experience with the SC I do have quite a lot with ECUs on the supra and other cars. The AEM has worked out pretty well for most guys but still not a lot of guys running them with much time on the setup. Have you thought about the HAL-TECH or the Electromitive? The Electromitive TECIII is in my mind the best ECU made it is very expensive but also once up and running the best you can get. The HAL-TECH is a bit more simple and has lot of very neat features as well. You can download the hal-tech OS at there web site and play around with it see what you think.
In my mind the only draw back to the hal-tech and electromitive systems are tuning on the fly. We all know it should only be done on the dyno with a wide band 02 but its very easy to try and fine tune on the street and of course this is were most problems with it come in. You said think out loud so some stuff to think about if your interested in going that rought.
In my mind the only draw back to the hal-tech and electromitive systems are tuning on the fly. We all know it should only be done on the dyno with a wide band 02 but its very easy to try and fine tune on the street and of course this is were most problems with it come in. You said think out loud so some stuff to think about if your interested in going that rought.
09-20-02, 02:37 PM
#5
Lexus Champion
Originally posted by NONE
Though I have limited experience with the SC I do have quite a lot with ECUs on the supra and other cars. The AEM has worked out pretty well for most guys but still not a lot of guys running them with much time on the setup. Have you thought about the HAL-TECH or the Electromitive? The Electromitive TECIII is in my mind the best ECU made it is very expensive but also once up and running the best you can get. The HAL-TECH is a bit more simple and has lot of very neat features as well. You can download the hal-tech OS at there web site and play around with it see what you think.
In my mind the only draw back to the hal-tech and electromitive systems are tuning on the fly. We all know it should only be done on the dyno with a wide band 02 but its very easy to try and fine tune on the street and of course this is were most problems with it come in. You said think out loud so some stuff to think about if your interested in going that rought.
Though I have limited experience with the SC I do have quite a lot with ECUs on the supra and other cars. The AEM has worked out pretty well for most guys but still not a lot of guys running them with much time on the setup. Have you thought about the HAL-TECH or the Electromitive? The Electromitive TECIII is in my mind the best ECU made it is very expensive but also once up and running the best you can get. The HAL-TECH is a bit more simple and has lot of very neat features as well. You can download the hal-tech OS at there web site and play around with it see what you think.
In my mind the only draw back to the hal-tech and electromitive systems are tuning on the fly. We all know it should only be done on the dyno with a wide band 02 but its very easy to try and fine tune on the street and of course this is were most problems with it come in. You said think out loud so some stuff to think about if your interested in going that rought.
Good point, and one of the reasons I like the Speed Pro, domestic guys have been using it for years and years, like Scott said I love the ability to plug in an AF ratio, plus the other features like a cold-start idle, etc. Decisions, decisions, Scott, the three of us could just try one each and see who's faster
...........- Jon
09-21-02, 12:13 AM
#6
Lexus Test Driver
Thread Starter
Anyone know if the NA ECU can even control 750cc injectors with the VPC?
I know Jeff ran 440cc injectors with stock ECU but that was high impedance, I thought?
I know Jeff ran 440cc injectors with stock ECU but that was high impedance, I thought?
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09-22-02, 02:20 PM
#9
Lexus Champion
He did, RC Engineering 440's with custom clips, stock rail, and a pump. He also had a Rebic IV and two aux 550's, but I don't think he ever used them, no need with the 440's at that level...
Jeff, where you at bro? Put down the firehose and help us build horsepower ..........
- Jon
Jeff, where you at bro? Put down the firehose and help us build horsepower
..........- Jon
09-22-02, 09:40 PM
#10
Originally posted by SC300T
I've heard alot of mixed things about the AEM... too complicated, hard to setup, easy to make a mistake on a fuel map, etc. But I've heard that it can also do so many things that would take five other boxes to accomplish. People also say that it has more stuff on it than the Speed Pro, although everyone that uses the Speed Pro raves about how easy it is to set the fuel maps, Plug in your desired A/F ratio, see how the unit corrects the map in the table, and go from there.
Chris @ Horsepower Freaks made a little boo boo and ran a Map sensor that didn't extend far enough to map his high boost. As a result, the AEM didn't have a fuel table for it, boost ran right off the map and melted a bunch of pistons - shortblock ruined.
But perhaps the AEM really is near ideal, and the safe way would be to just start out with the boost very low, and creep up gradually.
Any ideas?
I've heard alot of mixed things about the AEM... too complicated, hard to setup, easy to make a mistake on a fuel map, etc. But I've heard that it can also do so many things that would take five other boxes to accomplish. People also say that it has more stuff on it than the Speed Pro, although everyone that uses the Speed Pro raves about how easy it is to set the fuel maps, Plug in your desired A/F ratio, see how the unit corrects the map in the table, and go from there.
Chris @ Horsepower Freaks made a little boo boo and ran a Map sensor that didn't extend far enough to map his high boost. As a result, the AEM didn't have a fuel table for it, boost ran right off the map and melted a bunch of pistons - shortblock ruined.
But perhaps the AEM really is near ideal, and the safe way would be to just start out with the boost very low, and creep up gradually.
Any ideas?
lessee... there's Haltech, FAST, Motec, and AEM...
i think the AEM is the best for the $$$, while the FAST in my book the best period
AEM is also the EASIEST to set up; the Haltech requires you to slice the harness n ****...
if you're trying to save money; buy injectors off of a Buick Grand National website in lbs/hr... they are FAR cheaper and just as good
09-22-02, 10:02 PM
#11
Pole Position
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He is at Nopi right now but I'm not sure when he is getting back. Today was the last day if I remember correctly so you should be hearing from him soon.
Originally posted by Lex Luthor
Jeff, where you at bro? Put down the firehose and help us build horsepower ..........
- Jon
Jeff, where you at bro? Put down the firehose and help us build horsepower
..........- Jon
09-23-02, 08:47 AM
#12
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I run Speed Pro, now known as FAST and love it. We have had nothing but good results from it, and it has even saved us in a few situations.
Additionally, you can run more than 2 bar on a 3 bar map sensor with the Speed Pro, and they are going to be releasing 5 bar software soon as well which will allow for more boost than any of us will ever run on these blocks. I have already ran 32ish psi on the 3 bar with Speed Pro, and know that the Venom Tundra has run 42-44psi on the 3bar with Speed Pro, because Harv told me when I was talking to him (Harv tunes the Venom cars).
The Speed Pro is very user friendly once you get to know the software, and you can make your car 100% as driveable as on the stock ECU if you spend the time on tuning.
In my book I will not own anything besides Speed Pro (FAST) unless something comes out that absolutely eclipses it in numerous aspects at a reasonable price, which as of right now, nothing has... Maybe AEM when they get the closed loop wide band option figured out (have they done that yet), but right now I prefer the Speed Pro, and there are SOO many people with experience with it compared to the AEM that you can get technical support from all over.
-Ethan
Additionally, you can run more than 2 bar on a 3 bar map sensor with the Speed Pro, and they are going to be releasing 5 bar software soon as well which will allow for more boost than any of us will ever run on these blocks. I have already ran 32ish psi on the 3 bar with Speed Pro, and know that the Venom Tundra has run 42-44psi on the 3bar with Speed Pro, because Harv told me when I was talking to him (Harv tunes the Venom cars).
The Speed Pro is very user friendly once you get to know the software, and you can make your car 100% as driveable as on the stock ECU if you spend the time on tuning.
In my book I will not own anything besides Speed Pro (FAST) unless something comes out that absolutely eclipses it in numerous aspects at a reasonable price, which as of right now, nothing has... Maybe AEM when they get the closed loop wide band option figured out (have they done that yet), but right now I prefer the Speed Pro, and there are SOO many people with experience with it compared to the AEM that you can get technical support from all over.
-Ethan
09-23-02, 10:56 AM
#13
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low impedance injectors will work with the stock NA ecu... all you need to do is wire in either a MKIII or MKIV injector resistor pack.
as for ECUs... ive dealt with both Speedpro and AEM. I like speedpro because, just as you said, its pretty simple. but the costs involved (crank trigger, for NA you'll also need the speedpro electronic distributor) in mating it to a supra/sc300 are higher than that of the aem. the aem has more features than speedpro and as the next version comes out... will feature automapping and the closed loop o2 code will be solidified.
i have everything wired up on my car, im currently just waiting for an intake manifold to get finished, and my tire sponsor to sort out a tire situation. ill be sure to report my results
-brian
a slow '92 rsp sc300
as for ECUs... ive dealt with both Speedpro and AEM. I like speedpro because, just as you said, its pretty simple. but the costs involved (crank trigger, for NA you'll also need the speedpro electronic distributor) in mating it to a supra/sc300 are higher than that of the aem. the aem has more features than speedpro and as the next version comes out... will feature automapping and the closed loop o2 code will be solidified.
i have everything wired up on my car, im currently just waiting for an intake manifold to get finished, and my tire sponsor to sort out a tire situation. ill be sure to report my results
-brian
a slow '92 rsp sc300
09-23-02, 08:53 PM
#15
Lexus Test Driver
Thread Starter
Thanks!!!!
I wonder if there is a cheap solution to the ECU thing:
Parallel MAFs (like Clint) twice the air flow signal +
injectors that spray twice as much say 680cc =
air fuel ratios in balance or nearly in balance?
I have 750cc injectors right now (pretty close), I wonder if doubling the MAF signal would balance the whole system out? Or even be close so that it would just take an S-AFC to bring the balance back.
I wonder if there is a cheap solution to the ECU thing:
Parallel MAFs (like Clint) twice the air flow signal +
injectors that spray twice as much say 680cc =
air fuel ratios in balance or nearly in balance?
I have 750cc injectors right now (pretty close), I wonder if doubling the MAF signal would balance the whole system out? Or even be close so that it would just take an S-AFC to bring the balance back.