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I purchased a 91 police car (caprice) with 140,000 on 5.7 350 fuel injected motor.

There is a ton of emission crap on this motor that I am sure the computer needs to work right. I am planning on removing all emission stuff and total redoing the motor and going 30 over. My questions are as follows: Will the existing computer work ? can it be reprogrammed or will it need replaced? What mfg makes a replacement computer to use on a hiperformance motor?

Any suggestions on redoing the heads?

The trans is a AOD unit not sure if it is a 4L6E or 7004R, Is B & M the best choice for a shift kit?
 

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you can get a custom chip from <a href="http://www.fastchip.com" target="_blank">fastchip.com</a>... they did a custom chip for my k5 when I redid it. they can burn the chip so that you will not need all the emissions stuff.

a popular upgrade right now for the heads are the vortec's. you can get them a couple places for a little over $500, and that is complete. GM Performance makes a intake that will accomodate the TBI (I'm assuming you have TBI - if TPI I'm not sure what solutations there are for using the vortec heads).

all in all it was a decent upgrade in the stock power.
 

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Ah what ton of emmissions stuff are you talkin about?? O-2 Sensor?? EGR valve?? coolant temp switch??air temp sensor?? Lockup converter?? Cat converter. All you would be doing is screwing up your gas milage,getting less HP and damaging the trans by removeing anything.The reason that motor is so desirable in a rod is cause its got all that stuff you dont understand.Go get a 327 if you dont understand computer controled motors.The computer controls everything and thats were you get your power,milage,and drivabilty. You need to buy and after market wiring harness but DONT ripe everything off the motor you think is emmisions cause it dont have but a egr valve and cat the rest is engine mangement ;) Sound like you might do better selling it and buy a 70's 350 with a carb you will get better reasults.
 

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its a 4L60(not 4L60E)

good car, leave all the "emissions junk" because the computer will be happy. honestly there isnt much in there. takin off the smog pump will screw your belt routing, and anything else will screw your computer.

ive got a 91 with a 305 - real easy to work on.
 

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yea I dumped the air injection on both of them... one had to have a custom chip anyway, and they other one still have the pump on the serpentine with the sensors hooked up. runs great that way, but eventually I'll get a custom chip & dump the air injection pump too.
 

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in a lil nicer way i have to agree with phatt the police edition setup is a very desireable eng and computer controled setup the police chip is the same as taxi setup and gives good power and drivability just like it is if changed to a performance chip setup and removing the computer controlled devices would prolly be wasted money that could be spent on better upgrades else where i would love to have the setup that you are wanting to destroy in one of my current projects
 

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Sorry i did not mean to come off as nasty. I allways post like i am talkin in the shop with a friend .This subject allways comes up and my customers drive me nuts when they look all over the country for that motor than they want me to strip everything off it(posted with a smile) Wookie dont pull the injection pump off its there for a reason.Do you know what??(i can bust on him a little as i know him :) ) )Sorry if i sounded like a jerk i dont post very well. In the end you will be very happy with that engine and combo(just dont strip it LOL )
 

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I thought they only thing the air injection pump did was emmissions related? I know the EGR actually helps the engine cyl. run cooler etc. but I was unaware the injection pump actually did anything signifigant.
 

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Stay away from b&m-it stands for bowl movement, and is what your tranny is likely to look like after the b&m shift kit. Stick with transgo, or art carr for a shift kit. The stock heads? I would not recommend wasting money on modifying them. The nice thing about the police motor is, that they have roller cams, where the trucks don't, for future reference. Those little tbi motors are designed for torque, and it would be wise to maximize breathing with exhaust, headers, throttle body spacer, and free flowing air cleaner. The chip on that motor will add 18-20hp, based on the use of premium fuel-if you have to run cheap gas, then the chip is out, for the most part-once we make a chip for cheap gas, the improvement is pretty small, compared to the standard units for premium fuel. Use a 180* thermostat, either way. Underdrive pulleys work, as long as the alternator pulley is an overdrive unit, to maintian tolerable charging. Once you have the motor maximized with peripheral items, then you can think heads-world product torquers are the best aftermarket choice. Many peopl find that the vortecs cost more in the end, by the time they have to buy an intake, or modify the bolt pattern on the heads-the vortecs do not have egr passages, either-you might want to know that. As far as emissions go, keep the egr, for sure, the air pump is to lower emissions on warmup by adding air to the mix, then when warm, to heat the cat converter-it won't really help OR hurt you, if it does not get in the way, just run it, to keep the pulley arrangement, if not, or you are allergic to it, chunk it and deal with it.
 
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