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87 K5 chip???

87BrnRsd

87BrnRsd

1/2 ton status
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Apr 21, 2003
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Boone, North Carolina
Well, I kinda have two questions. I have an 87 K5 with TBI on a re-built 350 bored .030" over. I added cfm-tech's fuel injection upgrades and noticed a nice power gain. On top of that, I now have a set of afterburner headers and an edelbrock performer tbi intake with new sensors for it. One: how much more power can i expect from headers and the intake? And two: will I need to burn a new chip, or can I get away with just bumping up the fuel pressure since I have an adjustable regulator and guage? Thanks.
-Harrison
 
The stock chip shoulld handle your setup just fine. Bump up the Fuel pressure to around 14 psi. You can also advance your timing some to gain a little more power. It would be good if you had winaldl or a scanner so you can read the data. It really helps to have the data like knock counts and fuel to air ratio so you tune your FP and timing so you get the most out of it.
I am running pretty much similar to yours with a 600 CFM TB on a stock chip. I run 14 psi fuel pressure. I get a little better performance at 14.5-15 but. Fuel milage goes down a little and idle is a little choppy. 14 seems to give the best all around performance with 2 degrees advance. Thees settings work for me but I am at 5K foot elevation. Diferent elevations may require diferent tuning.
 
I was hoping you would reply. Your a wealth of tbi knowledge.:bow: Anyways, I live around 3500-4000 feet of elevation. I had the fuel pressure at about 13 psi with just the cfm-tech stuff. I recently turned it down to between 12.5-12 psi becuase it was a little rich. I do have winaldl and a laptop by the way, so as soon as i get a cable, ill be able to post up some numbers. Im not worried about fuel mileage, only best performance, since i only drive the truck to the trail and wheeling. Now, when i bump up the timing, is it best to unhook the tan wire? I did that to the engine when i put it in and it seemed to work good. Its running great now with plenty of power...im just trying to optimize it once i get the headers and intake on. How much power would a chip gain me if i use the proper data logging from winaldl, and burn it specifically for these mods? Is it worth the $300 from tbichips.com? Thanks for all your help.....thunder....you suggested the cfm-tech upgrades....................................................................................................................................................and.........:bow: the throttle response i gained was amazing.:bow:
-Harrison
 
You really don't need a new chip unless your its something major like heads or cam. It would run a little better with a chip but it should run just fine without it and no its not worth it... most of those mail order chips will never come close to a custom tune. best way to do it is either burn the chip/s yourself or put it on a dyno and let a pro do it.

Yes... you'll want to unhook the tan wire... that's your advance wire... kinda hard to time it accuratly with it hooked up because it'll through off your starting point.
 
I run flat tops +.030., Edelbrock cam and manifold and did have headers too and a throttle body spacer on a stock chip. I bought everything to burn chips myself but it ran so good on the stock one I haven't invested the time into writing and burning yet. You should be fine on that set up.
Like Thunder says, you can bump up the fp a bit but go easy as it's easy to overcome the injectors and it'll run way rich at idle and low speed.
 
Thats good to know that the stock chip will support these mods. I really wasnt looking forward to shelling out the cash for a chip.
-Harrison
 
But bear in mind that every motor is different so run Winaldl and see what sort of figures you're getting regarding temperature, BLM and knock counts.
Good luck!
 
southernspeed said:
But bear in mind that every motor is different so run Winaldl and see what sort of figures you're getting regarding temperature, BLM and knock counts.
Good luck!
Click to expand...
Yeah...I have a laptop and just downloaded winaldl. I have to get up some money for the cable though....and the usb adapter thing since my laptop is new.
-Harrison
 
I am glad the stuff I suggested works for you. As said. Go slow with the fuel pressure 1/2 lb change can make a big diference. I have gone as far as 4 degrees timing advance (with black/ tan bypass wire disconnected) without any problems or pinging as long as you use 89 or better gas.
Also Be sure drive your truck for a while after you make any changes in FP or timing. It takes 40 or 50 miles for the ECM to learn the new changes and get the block learn reset to the new settings. Then do some more scans/readings and adjust accordingly if needed. It took me a week of driving back and forth to work (40 miles) to get everything tuned right when I went to the bigger CFM TB. Getting full throttle performance was not that hard but fine tuning for fuel mileage took a bit of tweaking.

Oh and I will add a shameles plug for Eagle Mark. Affordible FI does good work. And he can work with you if you do need a new chip burned. I had them do some injector work for me long before they became a vendor here at CK5. Was very satisfied.
 
Connector is hard to find (I've never seen them sold) but you can make the cable for about $3, the plans are all over the internet.
 
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