OK before i get flamed, iknow this is not the proper and safe way to do this, but its a low budget build/car that is for fun. I was wondering if there is a ratio of # of check valves to pound of boost. The problem i am having is not a CEL because the map isn't seeing enough psi to throw it, but when the map goes from vacuum to a little bit of psi (monitered through the afc) it will stumble for a second then get down and dirty. It is more of a drivabilty problem than performance. Just trying to get the transition from vacuum to boost smooth so i can mat it anytime and not have to roll into it.
The setup 93 integra GSR 1.7 w/ 7 lbs on stock motor w/ dsm 450's and the afc set at -4% across the board. Any real input is appreciated. I have 8 check valves currently.

 

With 7psi you aren't going to need any check valves, so I would do away with them. Second, you should check your fuel settings. -4% isn't hardly enough with 450's. You're more than likely richer than Paris Hilton.

Homemadeturbo.com Engine Management FAQ, by TurboEF9

This will give you the upper limit for the current injector size.
As for obtaining those settings there are a couple of things to explain. Fuel flow rate difference.

This is the difference in flow based on the stock injector flow rate. For a Honda, 240cc injectors are stock. If you increase to 450cc injectors, your flow rate difference is a 46% increase. How do we figure that? Simple math: percent_of_difference = ((240 / new_injector_size) - 1) * 100
Second, an AFC does not control fuel injector pulse duration. This means we cannot compensate for injector latency in the fuel table for our larger injectors. Injector latency describes the scientific characteristic of how long it takes the injector to physically open. The larger the injector, the higher the latency. Since AFCs do not control the pulse duration directly, we compensate with a fixed percentage subtraction, otherwise, we would run lean in lower RPMs, even though our fuel flow rate has been adjusted based on the exact percent difference. The scale for common injector sizes used is 5% for 440-450cc, 4%, 390cc, 3% for 310cc.. then subtract 1 percent per 500 RPM increase. This will give us are starting point. For a boosted application, running stoichiometric is dangerous because of the high volume of air. To "play it safe", you want to run a bit on the stoich/rich side, so we increase fuel flow by 1% per 1000 rpms, trying not to top out a 5% overall increase. Why 5%? ..because your fuel maps are still increasing in pulse duration. So you're increasing pulse duration, and percentage
of flow rate at the same time. You'll get rich, very quickly. If you have VTEC, enrich by 1% more over VTEC VTEC crossover.
So, lets apply everything we've learned, and come up with base settings for 450cc injectors.

1) 240/450 = 0.53
2) 0.53 - 1 = -0.46
3) -0.46 * 100 = -46

So we have a 46% difference, we add our 5% for injector latency compensation, which leaves us with these settings:

1000 - 40%
1500 - 40%
2000 - 39%
3000 - 38%
4000 - 37%
--- VTEC set to 4400 RPMs ---
5000 - 35%
6000 - 34%
7000 - 34%
8000 - 34%

Application of these ideals will find your AFC Hack producing the smooth, safe, reliable power.


Other than that, the 1.7 GSR engine is a rare bird, so please get yourself some type of real management before you hurt it.

 

thanx man. i know its super rich but trying to keep it safe on the 1.7. When i had only 6 check valves though it would throw a map code under boost on 3rd and higher pulls. Nice feedback!