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-   -   stock port rew/ efr 8374 low on power? (https://www.rx7club.com/single-turbo-rx-7s-23/stock-port-rew-efr-8374-low-power-1157178/)

AlexG13B 09-02-23 06:32 AM

so my nozzle flows about 1,800cc compared to the aem which was like 1,500-1,600cc
ive always alought maybe it's too much but i have seen people run dual 10gpg nozzles, granted maybe it's just straight meth and not mixed 50/50 like me

here are my pulse solenoid settings. i'm pulsing a solenoid and just turning meth pump on or off
pressure like i said is logged at like 180-200 psi on average. im using an upgraded prometh pump and running -4 hise from tank to solenoid, and im using the stock washer tank and pump mounted right by tank so less distance from engine to pump

30 hz
40% dc -75cc flow in 10 seconds
50% dc- 125cc
60% dc- 150cc
70% dc- 190cc
80% dc- 225cc
90% dc- 295cc
100% dc- 320cc

Topolino 09-07-23 05:41 PM

I suppose the consolation in all of this (using far more nozzle capacity than ideal) is that you were using a 50/50 mixture, which likely kept you from flooding your engine w a deluge of water. Then again, had you been using water only, you would've discovered the problem instantaneously since it would've been obvious at that point.

Now that you're on the right track to implementing a suitable remedy (swapping in a much smaller AI nozzle), I recommend going w something in the 400-500 cc/minute range for your power goals.

As a GENERAL rule of thumb when using a 50/50 WM mixture, use a factor of 100 ml/min (cc = ml) for every 100 hp achieved; approx. 1.5 gph nozzle capacity per 100 hp. This is primarily a starting point for the 20 psi or lower crowd. If using water only, go with 1 gph nozzle capacity for every 100 hp produced.

Note: These are general "starting points" considering the variable factors of differing mfr pump pressures & nozzle flow ratings offered; more prudent to start at the minimal end, and work your way up as applicable.

And since you are already familiar w Rodney's AI offerings, I recommend snagging one of his newer nozzles rated at 0.022 orifice size (best atomization selection offerings in the industry in my view). Plan to pair that w a 3-slot atomizer, and then add a 4-slot atomizer to the order should you determine some extra capacity at that initial orifice size is ultimately needed.

If going a more traditional route for nozzle selection (using gph capacity ratings), a 7 or 8gph nozzle selection will be plenty enough flow for your application. You can certainly go up to 10gph to limit solenoid duty cycle, but you'd be sacrificing slightly less overall atomization in the process. In either case, you should see instant gratification on the butt dyno when chunking your existing 20gph nozzle for any recommended selection less than half that overall capacity.

Hope this info helps! Interested to see how it goes for you moving forward.

Valkyrie 09-07-23 08:56 PM


Originally Posted by AlexG13B (Post 12574240)
so my nozzle flows about 1,800cc compared to the aem which was like 1,500-1,600cc
ive always alought maybe it's too much but i have seen people run dual 10gpg nozzles, granted maybe it's just straight meth and not mixed 50/50 like me

here are my pulse solenoid settings. i'm pulsing a solenoid and just turning meth pump on or off
pressure like i said is logged at like 180-200 psi on average. im using an upgraded prometh pump and running -4 hise from tank to solenoid, and im using the stock washer tank and pump mounted right by tank so less distance from engine to pump

30 hz
40% dc -75cc flow in 10 seconds
50% dc- 125cc
60% dc- 150cc
70% dc- 190cc
80% dc- 225cc
90% dc- 295cc
100% dc- 320cc

320 cc in 10 seconds equates to 115 liters in an hour... that's the better part of 30 gallons.

ogmikeG 10-26-23 09:46 PM

updates?! :)

AlexG13B 11-17-23 04:19 PM


Originally Posted by ogmikeG (Post 12581609)
updates?! :)

no not really :(

AlexG13B 02-15-24 02:43 PM

well im back to try and figure this thing out. took a much needed brake from it. got tired of working on it and spending money with no result.

right now im pretty sure issue is with the meth system or weak ignition.


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