12.54 at 112mph in EVO VIII
Originally posted by Speedlimit
Fuel cut does put stress on the engine and drive train, however, its purpose is protect the turbo and engine.
Fuel cut does put stress on the engine and drive train, however, its purpose is protect the turbo and engine.
The reason the recommendation for resetting the ECU is that it "learns" the fuel cut parameters relative to temp, press and mass air flow and triggers it next time the same conditions exist; at least it did in our DSM's.
Thomas Dorri
Hi Tom,
This is another one of the "urban legends" that many DSMer's thought was happening I guess. Fuel cut seemed to occur at the same point over and over after making changes so the conclusion that the ECU "learned" it. Actually it was just duplicating the same conditions over and over.
Speedlimit.........
This is another one of the "urban legends" that many DSMer's thought was happening I guess. Fuel cut seemed to occur at the same point over and over after making changes so the conclusion that the ECU "learned" it. Actually it was just duplicating the same conditions over and over.
Speedlimit.........
Hi. Probably doing modifications this week. What is a good instrument to measure a/f ratio? I do not have access to an AWD dyno, and I don't own a wideband O2 or anything. Also, anyone have settings for the SFC for 20psi to keep a/f ratios within limits?
Hi, i think i saw you at byron raceway this weekend on the 5th of April? I was under the impression that your evo, if it was you at byron, was stock. Crazy runs btw, anyways...i was wondering what a stock evo dynos at and what 1/4 it runs. According to SCC it was 12.8? Don't really believe the SCC articles cause they ran a 15.8 1/4 mile because i was running 15.3's and 4's all day and there have been reports of 14.9's. Oh, and my wrx friend is in disbelief and i want to put him down so please do inform me.
Last edited by Spec V.tuner; Apr 7, 2003 at 01:24 AM.
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Originally posted by AMS
One way of reducing the MAF signal is with an S-AFC, it modifies the MAF signal by increasing or reducing it, thus telling the computer that there is more or less air going through the engine. By reducing the MAF signal (via S-AFC) you are actually raising the fuel cut level. For example lets say the the computer will initiate fuel cut at a MAF signal of 100 (arbitrary number). At 6K rpm the stock MAF signal is 100, the A/F ratio is 10.5:1 and you're hitting fuel cut , now you modify the signal with the S-AFC (or whatever other method is used, ecu mods, ect) and reduce it by 10% to 90 and now your A/F ratio is 11.8:1. (since the computer thinks the engine is getting less air it send less fuel). You've just leaned out the A/F ratio and raised your fuel cut level, but obviously there is a limit since you can only go so lean before combution temps go up and you melt a valve or burn a piston.
One way of reducing the MAF signal is with an S-AFC, it modifies the MAF signal by increasing or reducing it, thus telling the computer that there is more or less air going through the engine. By reducing the MAF signal (via S-AFC) you are actually raising the fuel cut level. For example lets say the the computer will initiate fuel cut at a MAF signal of 100 (arbitrary number). At 6K rpm the stock MAF signal is 100, the A/F ratio is 10.5:1 and you're hitting fuel cut , now you modify the signal with the S-AFC (or whatever other method is used, ecu mods, ect) and reduce it by 10% to 90 and now your A/F ratio is 11.8:1. (since the computer thinks the engine is getting less air it send less fuel). You've just leaned out the A/F ratio and raised your fuel cut level, but obviously there is a limit since you can only go so lean before combution temps go up and you melt a valve or burn a piston.
I am installing the emanage today with the fuel cut defensor, and it has also the ability to adjust ignition timing, I will post the map after I can get a dyno tomorrow.
Originally posted by Coolguy949
For now I think an AFC would be the only way to do that.
For now I think an AFC would be the only way to do that.
Originally posted by wing240
I am installing the emanage today with the fuel cut defensor, and it has also the ability to adjust ignition timing, I will post the map after I can get a dyno tomorrow.
I am installing the emanage today with the fuel cut defensor, and it has also the ability to adjust ignition timing, I will post the map after I can get a dyno tomorrow.
Installed the SAFC2 in my Evo 8 today, along with a Hallman boost controller. Did it outside in the snow (yes, it snowed here in NJ, in April). SAFC2 was a ***** to install, because it didn't have an English manual, and Apex was no help. Got it figured out though. If anyone needs wiring help with it, let me know. Also put in the new style Hallman boost controller. Trying to make it to the track on the next nice day out.
Anyone have SAFC2 settings for 20psi, with a safe yet powerful a/f ratio? Thanks in advance.
Anyone have SAFC2 settings for 20psi, with a safe yet powerful a/f ratio? Thanks in advance.
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Originally posted by TearItUpSports
Hey Martin,
Great track numbers. They are very encouraging.
I am a tiny bit confused on your tech articles though.
In one article you had a SAFC and boost control (which one BTW?) making about 300 WHP. In another article you have a catback making about 300 WHP.
I am going to assume that they are independant tests. Is that correct?
If so what does the combo of all 3 of those measure on your dyno?
Also are you going to start using something like the EMS? It sounds like something like that would work well as a one unit solution to a lot of problems. It may not be the easiest route, but might be the cleanest. I would be really interested in looking into one of those even if I keep my car mostly stock otherwise.
This is just my play car, and I would like to learn how to do something new. If my car is down several weeks while I tune something, its not that big of deal.
Hey Martin,
Great track numbers. They are very encouraging.
I am a tiny bit confused on your tech articles though.
In one article you had a SAFC and boost control (which one BTW?) making about 300 WHP. In another article you have a catback making about 300 WHP.
I am going to assume that they are independant tests. Is that correct?
If so what does the combo of all 3 of those measure on your dyno?
Also are you going to start using something like the EMS? It sounds like something like that would work well as a one unit solution to a lot of problems. It may not be the easiest route, but might be the cleanest. I would be really interested in looking into one of those even if I keep my car mostly stock otherwise.
This is just my play car, and I would like to learn how to do something new. If my car is down several weeks while I tune something, its not that big of deal.
Martin
you peps are lucky that you have no jumpy rpm signals on the safc. us 6g72'ers have a huge problem with jumpy rpms using a safr or hks afr. i have an afr and dont have a fix yet so my rpms jump like MAD. but we tuned up to 8Krpms taking this into consideration. after my break in period i am putting a new piggy back system that acts like a standalone; control timing and all that jazz.
SWEET NUMBERS THOUGH....makes me really wonder why i spend soooooo much cash on my car when your cars could whip up on mine stock.
i am sure i will get flamed for this. but if you are gonna increase injectors are you gonna increase the fuel pump, maybe a boost sensitive fpr. mine works great. at idle my fuel psi is around 45 and during the onset of boost it climbs to 65. my dyno curve is almost perfect straight upward line. (thats because s/c though)
AFTERMARKET support for your cars is amazing. the car has only been out for a month or so and there is like 3-4 companies postin on this board with numbers in the 12.5 range. a guy on club3G board, with the s/c kit that i have is throwin down like 293whp and is only makin a 13.6. Traction is a huge problem though. well sorry to get off track. GOOD JOB and KEEP IT UP
SWEET NUMBERS THOUGH....makes me really wonder why i spend soooooo much cash on my car when your cars could whip up on mine stock.
i am sure i will get flamed for this. but if you are gonna increase injectors are you gonna increase the fuel pump, maybe a boost sensitive fpr. mine works great. at idle my fuel psi is around 45 and during the onset of boost it climbs to 65. my dyno curve is almost perfect straight upward line. (thats because s/c though)
AFTERMARKET support for your cars is amazing. the car has only been out for a month or so and there is like 3-4 companies postin on this board with numbers in the 12.5 range. a guy on club3G board, with the s/c kit that i have is throwin down like 293whp and is only makin a 13.6. Traction is a huge problem though. well sorry to get off track. GOOD JOB and KEEP IT UP
Originally posted by SuperchargedGTZ
i am sure i will get flamed for this. but if you are gonna increase injectors are you gonna increase the fuel pump,
i am sure i will get flamed for this. but if you are gonna increase injectors are you gonna increase the fuel pump,
However the injectors are only good for "so much" power and will eventually need to be replaced depending on how far the car is in the mods department.
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the stock 560cc/min inj. will support close to 400whp (at the front wheels), Safely I'd say 375whp. On DSM's we've taken 550cc/min inj. up to that level and maxed them out. BTW the stock FPR is boost referencing, so for every psi increase of intake manifold pressure there is a psi increase in fuel pressure. We'll be doing the fuel pump install here shortly and if it works out well it will only be about $125 for the whole pump and install kit.
Martin
Martin


