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- - 450 tuning (https://www.homemadeturbo.com/engine-management-10/450-tuning-36482/)

Sorry for the long post by this kinda sucks. I was supposed to be putting my turbo kit that I've been piecing together on my prelude ( Eclipse parts on the H23) this coming weekend but know I don't think I'll make the dead line. I installed the 450's this weekendand it all sealed perfect no fuel leaks. I set the SAFC II to:

800 -40
1400 -39
2000 -38
2600 -37
3200 -36
3800 -36
4400 -36
5000 -36
5600 -36
6200 -36
7000 -36

The H23 has 240cc injectors just like almost every other honda so these settings should have got me close to good readings. The car is stock except for CAI. On the PLX m300 the car was idiling at 16.**. I had to turn the fuel up to around -33% at idle to get the wideband to read stoich. I let the car run for a while at these settings. I didn't rev it up mainly because I was scared to running at -33% at idle but it ran ok, no black smoke, and didn't smell rich and the a/f ratios on the WB were pretty stable but the reading bounces around anyway( does anyone know how stable it should be at idle because even with the stock injectors the ratio bouces around a bit). If any of this doesn't sound right then someone please let me know. The math does not add up here so I cut the car off and put the original injectors back in. Switched files so I was at 0 correction and cranked the car again and the wb read stoich at idle and all the right readings when I got on the gas so I don't think that the WB is off calibration. My stock injectors look like any other 240cc honda injectors I've ever seen and the dsm's are blue tops so I'm sure they are 450's. Any ideas why it needed so much fuel. Someone metioned that the injectors might be clogged and to get them cleaned but that costs more that what I paid for them. Any ideas. Thanks

At low opening times, 450's are a bit slower than your stockers. Its normal for a 450 to want to idle at 2.1-2.3ish ms, and seeing how a stock 240 idles at around 2.8ish ms, your -33 correction is nothing to worry about. As the opening times get bigger, the 450's will start to really flow more than the 240's, and your corrections will get bigger on the AFC.

I just read that, and as usual I dont explain things good. Hope you got it.

That may be true but then whya would everyone else with a stock honda and a safc with 450 run 40% correction and I would need 33%. Thanks

By stock do you mean non-boosted?

More negative correction means less fuel (I think). My boosted setting were all in the -30's. O0

I explained all of this in the FAQ... Leed is talking about injector latency compensation. Check out Section 2 of the FAQ.

Thats true you did explain all of that for 240cc injectors which I have and these were the settings you suggested:
1000 - 40%
1500 - 40%
2000 - 39%
3000 - 38%
4000 - 37%
--- VTEC set to 4400 RPMs ---
5000 - 35%
6000 - 34%
7000 - 34%
8000 - 34%

Since I don't have vtec I did't increase the extra 1% so I did the same settings. I know they are only a base but why would I need to richen it up so much more the latency should be the same on the injectors. I wonder if it has anything to do with the fact that everyone else uses saturated stock and mine are peak and hold. Maybe the ECU is set up to read differently? And no the turbo is not on the car yet I wanted to get the injectors on and working before I put everything else on. This is confusing the hell out of me.

Quote:

Originally Posted by kylecrews

The settings TurboEF9 goes over in the the FAQ are for the popular DSM 450s, or so i thought...try reading the FAQ again.

1) Xenocron is right, those settings are not for 240s, they're for 450 injectors.. which you stated you were using above.

2) 240s and 450s do not have the same latency. 450s have a larger mass, therefore, at lower RPMs open and close slower than 240s. If you did a straight flow difference cut, (46%) you would run lean, because of this increase in latency. 240s would open quicker, thus 240s would open quicker, and release more fuel than 450s (which take longer to open) at the same pulse duration with the straight flow differential applied.

3) It has nothing to do with saturated, or peak and hold. Those are just two methods that the ECU uses to control the injectors. IT has nothing to do with thier fuel flow.

Mostly has to do with the fact that DSM injectors have a very heavy pintle (rod in the injector that moves up and down, opening and closing) compared to the stock 240 injectors.

Most larger injectors that you buy these days (RC, Precision, maybe Tuner Toys, not sure) use a disc which has very little mass and might actually open quicker than a pintled 240cc injector.

Sorry I did not explain that very well before, I ment to say that the settings TurboEF9 gave were for putting 450dsm injectors into a car that has stock 240cc injectors which i have and the latency correction is around +5%. I have 240cc stock injectors and put 450cc dsm injectors in with no turbo just to tune the injectors and did the -40% correction ( -46% + 5% for latency) and the WB02 read 16.** when I started the car so I had to increase fuel to -33% to get it to idle at a hair above stioch and it ran fine for several minutes at stoich with -33% correction. That is what I want to know is why I had to compensate +14% correction for latency instead of 5%.