Texas GN
 

Jack, just bought a 1987 25k GN that has been in a warehouse for many years here in San Antonio Tx. The car has had a few mods on it but i think for the most part it is stock. The mods are dual exhaust 2.25 ,headers, gauges (boost,temp,oil pressure,temp) hypertech chip (PT# 41 373). Can't seam to find any info on a 41 373 but there is plenty of info on the 41 372. I changed the gas tank out because it was full of rust and changed the fuel pump to a Walbro 255lph.
Oh, one other thing I have a hot wire kit for it too. I noticed it is running lean, the plugs were very clean; to clean even after 500 miles. Anyways I would like to get the car into the hi 12s low 13s. I need you to put me on the right track, you said something about 42lb injectors and a chip? Can i use the chip i have? Are the Valve springs up to the tasks? I hear they were weak too. Thank again, Glen

Sounds like A BEAUTY.. I didnt see anything about the fuel filter being changed out. You should definatly do it If you havent already.
You will need a chip for the #42 inj Im sure Jack has some in stock
Good luck
Mike
Post up some pics :) !

Texas GN
 

Thanks, I was planning on ordering the injectors asap but what about the Hypertech chip? Should I scrap the one that's in there now? Or should I try it with your 42 lb injectors?

Thanks Glen

Hi Glen,
Your going to need a new chip for larger injectors. Chips have come a looong way since that hypertech chip. It was most likely intended for use with stock injectors.
Chips now a days are burnt specificly for the injectors. Should you go to a larger injector after the #42s say maybe #50s same rule will apply
Hope this helps

Yup, Mikey is right.
First thing is work on the fuel system, which you have already started. I agree with Mikey, replace the fuel filter if you haven't. Does it have an adjustable fuel pressure regulator? All chips burned for this car require that the fuel pressure be set a bit higher than the factory non-adjustable unit is set for. Factory is 30#, I think, and most chips want you to set it for 42-ish.
Make sure everything is running right, FIRST. Then injectors and a chip. And as said, chips are programmed based on injector size. After that, if you want more go, then turbo, and/or a higher stall converter. Oh, don't forget, you are going to need to put tires in your budget.

Here's my car! 1987 Buick Grand National, 25k miles, just needs a little kick!

Texas GN
 

Thanks Guys, Starting to feel better about this project. I did change the fuel filter first thing when I pulled it out of the warehouse. That’s how I discovered the tank was shot. One thing I did not think about was a new regulator. Is there a replacement for the original position or just mount a Holley underneath somewhere. (Is there a recommended part number from Cotton's) Back to the fuel injectors, is the 42lb best ones for a stock block and turbo? Or can I just skip the 42s and move on to the 50s like previously discussed.

Thanks again for your assistance!
Glen

Give Jack a call, and he'll set you up with a good regulator that mounts in the factory location. As for injectors, the biggest that you can go without modifying the computer is 60#-ers. (Actually, I think they may have something a little bigger. Not sure.)
The chips for the 60s are supposed to be pretty good for anything from mild to wild, so I would recommend going with those and a chip to match. You don't want to buy a chip for 42s, then upgrade injectors, and have to buy another chip, then upgrade injectors again to 60s, and have to buy another chip. Go as big as you can. It will be good for what you have now, and will be ready for future upgrades.
Just to be sure, talk to Jack about what you have, what you want now, and what your plans are for the future. Just remember this. When I built my toy, I started out saying I only wanted to put it into the 12s, and I'd be happy with that. Then, I just wanted low 12s. Then once I got a low 12, I just wanted an 11.................well, now I am getting a motor that should blow right past the 10s and put my waGoN in the 9s. So, keep that in mind. Most people don't stop with one little upgrade.

Remember that line.. If I knew now what I didnt know then.
I personally would go # 50s. You could easliy hit 13s/12s with stock injectors. Although from what you told us there could be some fueling issues. Replacing the injectors may be wise. The boost reg would be on the fuel rail
When the boost bug bites you will have plenty of room to grow

Too funny Brian beat me to the punch ..:D