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Discussion Starter · #1 ·
Got the stroker motor put back together. At 8psi I had to end up cranking the boost fueling and full throttle fueling to max on the aero commander to get 12.4 afr. Now that I have a few hours on it I went ahead and adjusted the boost up to 12psi. Now the afr sits at 14.2. Stock fuel pump (Only 30hrs on it) and stock injectors with a third injector from the aerocharger kit. So question is what options do I have to get more fuel to this thirsty hog? Recommended vendors would be nice aswell if fueling system components are required (Regulator, better pump, injectors, ect...) Thanks all -Chris
 

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did you check your fuel pressure?
some stock fuel pumps have been known to go bad, or put out low pressure.
I think it is supposed to put out 39psi.
 
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If the stock pump is truly done(check fuel pressure?)..call Rayce at K&T..they already have a return style set up with an upgraded pump and adjustable boost referenced regulator..not hard to do and works great...should give you fuel for days.. PM me if you need his Cell number.
 

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Highoctane you are a true gear-head. I don't know if that's what you do for a living but i truly enjoy reading your post and responses. Also I like the fact you have a 4, I know who to look for when I'm struggling with something.
 
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Highoctane you are a true gear-head. I don't know if that's what you do for a living but i truly enjoy reading your post and responses. Also I like the fact you have a 4, I know who to look for when I'm struggling with something.
Thanks..definitely proud to be a "gearhead".. I USED to do it for a living..now I work for Uncle Sam..and just "do it" as a hobby...
 

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Fuel pressure and boost should be 1 to 1. So if fuel pressure is set to 40 psi(at idle) and you pull 10 pounds of boost the fuel pressure should go to 50 psi.
 

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Discussion Starter · #8 ·
I guess I could try checking fuel pressure. Is there a test port inline somewhere I overlooked? Not sure if the pump is actually done or not. May just simply not be able to keep up and if that be the case would a rising rate reglator not help or even just the airtex jeep pump replacement without the regulator? Or must I do both or worst case do the above return style system? Thanks for the help
 

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Most of the stage 1 turbo kits dont use rising rate regulators and dont need to. The stock pump works fine for most people... but they can and do go bad.
depending on what year RZR you have there should be a test port on the end of the fuel rail. I don't remember if the Aerocharger kit you have changes that or not.
I would call Aerocharger, since you have thier kit and they can help you trouble shoot it better.

Kind of like Askin said, you need more fuel pressure than manifold air pressure.
If you have 15psi of boost, and 14.7psi of barrometric pressure (sea level) that is 29.7psi of air in the manifold. if your fuel pressure is below the stock 39psi then it could cause a lean condition. Imagine you had 29.7psi of air pressure, and only 25psi of fuel pressure... no fuel would come out of the injectors! That is why high boost systems usually use a rising rate fuel regulator. As the boost increases the fuel pressure increases to maintain the proper AFR.
 

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With jumping the boost up you will need an upgraded pump and adjustable boost referenced regulator. It's cheap insurance and as HighOctane stated Rayce as them in-stock if you get in a pinch.
 

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Discussion Starter · #12 ·
Bigger third injector did the trick. With 60# and the aerocommander at 2 lights I'm at 11.6. Now just have to raise limiter or re-clutch. The added power found the 7k rev limiter real quick!
 
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