Fitech Meanstreet 800
I'm curious about something. Why is it that the Meanstreet 800 is only rated at 800 Hp, when the fuel delivery contradicts that?
It has 8X62 lb/hr injectors. With 0.5 BSFC for gasoline, Hp = 8X62/0.5 = 992 Hp.
Meanstreet 800 Hp 8X62/0.5 = 992 Hp (way off from 800)
Go Street 400 Hp 4X56/0.5 = 448 Hp (pretty close to 400)
Go EFI 4 600 Hp 4X80/0.5 = 640 Hp (pretty close to 600)
Go EFI 8 1200 Hp 8X80/0.5 = 1280 Hp (pretty close 1200)
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Great question. I have personally only worked with the 600 units. I know the 400 and the 800 use the same injectors. The 400 runs something like 46psi fuel pressure, where the 600 runs 58psi. I wonder what the 800 is regulated at. If it is the lower pressure, a simple regulator swap would fix that.
Yes, my wife's '71 vette that I put the 600 on does indeed have 58 psi pressure, because I put a fixed gauge on it right at the input. I'll be doing the same on my 800 to see just what it is. Good point.
Good deal.... I recommend everybody install a fuel pressure gauge. Very important for troubleshooting and tuning. Fitech never mentions this. Good luck. Look forward to your results.
I got a response back from fitech tech and they said the reason why the meanstreet is rated lower than the others in relation to the size of the injectors, is because it's pressure is regulated at 43 psi. I'm waiting on a return email from fitech on if there was a particular reason why they limited the pressure to 43 on that model.
I have heard of guys using the 58psi regulator on the 400, but never seen any data or results. Can see any reason why not.
I go the other way, I use the 43 psi regulator on my 600HP unit. My engine is only 3.5L (215 ci), so it helps keep the injector duty cycle above 1% at idle.
My guess the reason they use 43 psi on the Mean Street is just to create differentiation in the product line.
Well, if it wasn't for this one horse town, I would have been able to start my car for the first time with EFI, but couldn't get the AN fittings I needed for connecting the fuel pump up to the fuel line. So, I ordered what I needed from Summit Racing, and will most likely have it by Tuesday. Today I completely wired up the Fitech Meanstreet, including tach, power, accessory, fan relay, fuel pump control, and engine temp sensor. Also got my new 0-100 psi fuel pressure gauge at the fuel inlet of the fitech. Also finished hanging and restraining the fuel return line. All toll, that was a 12 hour day! 
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Ok, I think I'm ready for chassis dyno tomorrow! I got the Fitech Meanstreet 800 tuned to my engine well enough to have it idle without stalling, and it loses traction on the road at about 1/4 throttle when I punch it there, that it didn't do with the carb. Glad I took the day off, because it took till now from 8 this morning to get it to this point.
I realized last night after I got the fittings to connect my monster fuel pump to my fuel line and couldn't get the Fitech to start the car, that I needed to ground the Fitech to the frame. What, nothing in the kit to do this! So first thing this morning was going to ACE and picking up the correct bolt to wire ground it, then the handheld controller started working consistently, and the prime fuel started squirting in, and it almost started, but immediately fouled the plugs. So, I had to cut down the prime fuel from 170 to 50 to stop that, cleaning the plugs on each change. Then was able to fire it up and idle with my foot on the gas, so I had to call Fitech tech line and they walked me through the IAC adjustment to keep turning up the throttle a little at a time until I finally got it to idle without my foot, and an IAC of 3-10. Normally the recommended setting is a 1/2 turn on the idle screw, mine with just 5 in Hg with the cam I have had to be turned over 4 turns. The Fitech tech guy had to consult with others after he heard from me what this Fitech was going on.
So, I proceded to take it on the street and it died as soon as I tried to accelerate. I then began to increase the the acceleration pump settings, because It wasn't getting enough fuel, another good reason to have AFR meter in the car. So I had to go up from 0 on those to the settings below before it finally started to respond. You would sure think this crazy thing with all its sensors could tell if I was going lean without me having to tell it to give more fuel, but oh well.
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Oh, it idles so nicely now! I put in the new TPS sensor and new intake system and recalibrated the TPS, and it idles great! I ran it for awhile and looked at the plugs. They were running a little lean now with the changes, so I changed the 16.5 fitech AFR idle setting down to 16 and will check the plugs again. You have to keep checking the plugs, because the overlap in the cam I have skews the results of the AFR reading at idle to appear leaner than it is.
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