650's

[TC Mueller]

650's to big for a big 16g and an SAFCII?
either going that route or a big 16 and evo8 560's

what would you guys reccomend

 

[chuckg]

do you have a wideband? you're probably running way rich.

No, I don't have a wideband. On my safc i have to add like +6ish all across the board to keep knock down, which seems kinda rich to me. Anything below that and it starts pulling timing and knocking really bad. Any ideas?

 

[Karma]

Eprom!

 

[2gGSX]

I would go with 750's or bigger and have the eprom burned to the injectors. This way if you go larger you can grow. Plus you can get close to using up the 650's with that turbo and cams.

This depends. If he's comfortable running his injectors to 95% IDC he'll be moving 4.13 lbs/min of fuel, which is enough for 45 lbs/min of airflow at 11:1 AFR.

Nope it doesnt to me. My brother is running about 19psi on his 550's and seeing a little over 70%.

This makes absolutely no sense. On a 1g that equates to 2.39 lbs/min of fuel at 70%. There is no way he is making 300 awhp with that much fuel unless he's running AFRs in the area of 14:1 or leaner.
Even if they were 80%, on a 1g that's still 2.73 lbs/min, which seems very low for 300 awhp.

 

[JayRolla]

This makes absolutely no sense. On a 1g that equates to 2.39 lbs/min of fuel at 70%. There is no way he is making 300 awhp with that much fuel unless he's running AFRs in the area of 14:1 or leaner.
Even if they were 80%, on a 1g that's still 2.73 lbs/min, which seems very low for 300 awhp.

Im not lying, its actually around 76% but he is not hitting 80%. So it does make sense unless the logger is wrong.

 

[2gGSX]

The IDCs may make sense but the dyno numbers do not. You'd need close to if not more than 35 lbs/min of airflow to be seeing 300 awhp. Like I stated above, with the amount of fuel he's flowing there is no way he's supporting that kind of airflow.

For example, CanadianTSi is maxing his 650's to support 47 lbs/min of fuel. That's 4.35 lbs/min of fuel for 47 lbs/min airflow, translating to an AFR of approximately 10.8:1 (the exact number may or may not be near this, although this is likely within .5).

Going off of that for this other vehicle, 76% IDC on a 1g with 550's equates to 2.59 lbs/min of fuel. For 35 lbs/min of air, that equates to a rough AFR of 13.5:1 give or take 0.5. Granted this example (and it's calculation) is nowhere near perfect, it gives you a good idea of the point I'm trying to make.

 

[CanadianTSi]

For example, CanadianTSi is maxing his 650's to support 47 lbs/min of fuel. That's 4.35 lbs/min of fuel for 47 lbs/min airflow, translating to an AFR of approximately 10.8:1 (the exact number may or may not be near this, although this is likely within .5).

Thats pretty much dead on

As for the Dyno numbers, some dyno's read alot higher than others. The Dyno that I run on reads exceptionally low for instance. I take most dyno numbers with a grain of salt...