Yeah that is what I was thinking too I have 2 kinds of zeiner diodes here.. one let's. Thur too much and the other only let's . 3.5 volts. I have been messing around with it to see how close I can get it to cut voltage. I have tryed a 4.7 and a 5.1 volt. Now I have 4.3v on its way. The 4.7 volt only let 3.5 thru. I don't thing the 4.3 will work either. But I will find out
good old 50cent map clamp
- Thread starter 525gte
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ok so i wired in the 4.3 volt. and it lets thru 4.35v.. now i dont seem to have control over the sfac.. i am adding a ton of fuel and it does not seem to be resopnding at all to what im telling it to do.. does any one know why this is not contolling fuel.. ? and it still works fine on lo throttle.. its just not adding any at hi throt.. and i know this is not safe and not the right way. but i want to have it for the next dyno day. to be honest i hardly ever have ny boost controller even on. it start to lean amost instantly at 34oo rpm. and shows no sign of it slowing down and i have maxed out the sfac adding as much as i can at that point. any ideas? maybe you cant run the clamp method with
the sfac?
the sfac?
Definitely check your fuel lines, for both size, and kinks. Have you had this problem before? It almost sounds to me like you're running a fuel line that is either damaged (causing a bottleneck), or just too small for the application.
ifyouaint1sturlast
Banned Scammer - I'm whitemike.
525gte;1846437 said:
If it works on LO and not HI .. perhaps it's not detecting your throttle position sensor ..
Yeah they definitely go AFTER the SAFC. You only want to stop the ECU from seeing more than 4.3v on the map signal wire. You don't want to mess with the signal going into the SAFC.
The whole problem behind using diodes is that the ecu thinks you're running 14.5psi of boost from the time you hit 14.5psi all the way till whatever your real max boost is (lets just say 20 psi for this example). So to keep from running lean and blowing it up you need to tune at WOT @20psi with the SAFC to make sure you add enough fuel back in to not run lean, but the downside then is that at 14.5psi you will be running very rich and then it will slowly taper back to correct AFR when you near 20psi. That's not even close to ideal. The other downside is that you will be running the same timing from 14.5 to 20psi which is not usually a good idea. You might get knock, which will cause the ECU to retard the timing and will kill your power. So that defeats the whole point of raising the boost. You might also get BAD knock, which will just leave you with a blown engine. You also need to be careful you don't run out of fuel since you're running more boost without upgrading the injectors. So, in summary, not good.
The bigger fuel injector method is the safest way to run higher than boost cut on a stock ECU. Don't try upgrading the map sensor on a stock ECU, it's pointless because the fuel injectors can't handle providing all the extra fuel anyway. Just upgrade the injectors. 550's will raise the 1JZ boost cut to about 19psi after you tune them with the SAFC. 440's will give you about 17psi capability. You want to get a calculator and figure out how many percent larger the new injectors are than the stock ones, then stick that number (as a negative correction percentage) in the lo map and in the hi map. Then fine tune the hi map at WOT with a wideband and you're set. There's also vF tuning for the lo map, but that's another thing... you can search for that on here if you want, it's been covered 100 times.
The whole problem behind using diodes is that the ecu thinks you're running 14.5psi of boost from the time you hit 14.5psi all the way till whatever your real max boost is (lets just say 20 psi for this example). So to keep from running lean and blowing it up you need to tune at WOT @20psi with the SAFC to make sure you add enough fuel back in to not run lean, but the downside then is that at 14.5psi you will be running very rich and then it will slowly taper back to correct AFR when you near 20psi. That's not even close to ideal. The other downside is that you will be running the same timing from 14.5 to 20psi which is not usually a good idea. You might get knock, which will cause the ECU to retard the timing and will kill your power. So that defeats the whole point of raising the boost. You might also get BAD knock, which will just leave you with a blown engine. You also need to be careful you don't run out of fuel since you're running more boost without upgrading the injectors. So, in summary, not good.
The bigger fuel injector method is the safest way to run higher than boost cut on a stock ECU. Don't try upgrading the map sensor on a stock ECU, it's pointless because the fuel injectors can't handle providing all the extra fuel anyway. Just upgrade the injectors. 550's will raise the 1JZ boost cut to about 19psi after you tune them with the SAFC. 440's will give you about 17psi capability. You want to get a calculator and figure out how many percent larger the new injectors are than the stock ones, then stick that number (as a negative correction percentage) in the lo map and in the hi map. Then fine tune the hi map at WOT with a wideband and you're set. There's also vF tuning for the lo map, but that's another thing... you can search for that on here if you want, it's been covered 100 times.
Yeah I know all that. I have 440s in it now.. and it will only make 15.5 befor cut.. some times it will make 17.. but I also have 660s sitting on. My shelf.. and I was told that because u have to pull more than 20 percent that the 550s and 660s wiare not safe to run with the sfac. So I have never tried to istalle them.. lol so I was just going to save them for standalone nextwinter
So I guess I have to say f the 50 cent clamp.. no matteer how or where I wired it in at I had no high fuel control. I tried every way u can do it.. but here is the fun.ny part.. I took it out.. ran it stock with just th sfac.. grabbed a buddie and whent out to retune.. just pulled 20.2 with a 11.6 afr. And no fuel cut.. ?? Did it 3 times. 2 at 19.6 and 1 at 20.2.. go figure right.. car feels amazing too.also no knock showing. Going to do some more testing later when it gets colder but if it makes 19 I'm good with that still planning on a re dyno on the 22nd. So I should get much better bumbers now that all my issues are fixed.. ill let you know