Results 1 to 15 of 17

Thread: 88 chevy 1500 tuning issues

Hybrid View

Previous Post Previous Post   Next Post Next Post
  1. #1
    Electronic Ignition! typhoonss's Avatar
    Join Date
    Mar 2014
    Location
    Tampa, Fl
    Age
    44
    Posts
    10

    88 chevy 1500 tuning issues

    I have had this motor for almost a year as a daily driver now. I have for the most part drivability idle to 3200rpm with out knock and seems to run pretty good. Where my main issues are is it may break the tires loose a little off the line so it seems I may not have enough something there and also after about 3/4 throttle it drops off. My idle seems a little high usually in park around 1100-1300 and in drive with brake anywhere from 800-1000. The vehicle is a 88 chevy 1500 reg cab reg bed weighs 3960lbs without me in it. here is the motor build:
    motor: ATK SP03 357 4-bolt .040 +12.3cc Dish pistons 9.7:1 w/64cc

    cam: Comp Cams 12-262-4 1,500-5,500rpm 218/224 @.050 .464in/.470exh. lift LSA114

    lifters: COMP Cams High Energy Hydraulic Lifters 812-16

    pushrods: comp cams High Energy Pushrod Set Chevy 262-400ci w/Flat Tappet Cam 5/16 7.794

    timing chain: Magnum Double Roller Timing Set 1955-91 Chevy Small Block V8 265-400

    springs: COMP Cams Valve Springs 26918-16 Beehive 372 lbs./in

    rocker arms: Competition Cams 1417-16 Magnum Self-Aligning Roller 1.52 ratio, 3/8"

    harmonic balancer: ACDelco Harmonic Balancers 12551537 6.75in cast iron, internal balance

    Flexplate: Gold Series SFI-Rated Chromoly Steel Flexplate 1986-97 Small Block Chevy 350 Gen II

    oil pump: Melling M55HV High Volume

    Gaskets all Felpro
    Bolts all ARP except mains and piston rods

    Vortec heads 062
    Edelbrouck EPS Performer for vortec heads
    TBI adaptor aluminum
    TBI bored to 50mm with tbi spacer and #80 cop car injectors adj fpr w/17-20psi (17psi at 90's F and 20psi under 65 F)
    stainless midtube headers 1 5/8 to 3in
    msd blaster coil
    electric fans
    upgraded to 3 wire o2 sensor
    I have a 700r4 trans rebuild about 3yrs ago with the extra clutch packs and upgraded valve for firmer shifts(im not a transmission person had a buddy build it who has a transmission shop)
    FTI 2,400 stall convertor
    3.42 gm posi rear
    255/60r15 tires

    I have been reading post for years learning and tweaking the setup but I am getting stuck at this point. I know I will only get 5000 rpm out of the tbi which is fine.
    I do not have a wideband o2 for testing from what I have been reading seems I might need t get one.
    I started with Dave w. Performance AMUR bin file and have gone from there. I just changed the timing a little and have a little better low end and during normal driving but still 3/4 throttle up drops on it's face. Here is the bin files and logs. Oh yeah it is a 7747 $42. The datalog .csv would not upload so I zipped it.
    Any help would be greatly appreciated. I hope I got all the info and files you need to take a look.

    Also just to make sure this is working corretly I have a raspberry pi running android connected to a 5in touch screen running aldldroid which is where I datalog from and is also a touchscreen gauge cluster when driving.
    Attached Files Attached Files

  2. #2
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    422
    You can tune using a NBO2 and BLMs. I like using a wideband myself. I learned on the 7747 ECM. I switched two trucks over to the 7427 PCM for a multitude of reasons.... You should look into swapping one in and consider it yourself.

    Post pics of your touchscreen setup please. I'm interested in the layout you have there.

  3. #3
    Electronic Ignition! typhoonss's Avatar
    Join Date
    Mar 2014
    Location
    Tampa, Fl
    Age
    44
    Posts
    10
    off topic here is the touchscreen. I am also putting a 7in in the glovegox which will run a home automation linux system and also be a wireless router for sensors around the truck and leds. 20180212_135951404_iOS.jpg20180212_220317041_iOS.jpg

  4. #4
    Fuel Injected! CDeeZ's Avatar
    Join Date
    May 2012
    Location
    Jokelahoma
    Posts
    422
    Very cool thanks for sharing. I love the GMT400s. Have two of 'em.

    If you were to switch over to the 7427 PCM you could use Daves spreadsheet to make dialing it in easier. As far as which wideband I have an two different AEM 30-4110s installed in each of my GMT400s. The 7427 can be made to log wideband data directly in the datastream making it even easier. That's what I would do.

  5. #5
    Electronic Ignition! typhoonss's Avatar
    Join Date
    Mar 2014
    Location
    Tampa, Fl
    Age
    44
    Posts
    10
    OK I have spent about 5 hours reading posts over the past 2 days and I have changed the spark table, added a little more at idle and some to the 60-100 map in the 1800-3200 range. I also added a degree to the pe so it is at 3.52 now. I also changed the BPW from 110 to 120. I took a drive and datalogged and used the vortec ve excel sheet to correct the VE tables. It did not fall on it's face in the higher rpm but still stumbled a little. So I added a little more timing higher map and rpm then took another drive. Here is where I am at now. Idle a little high, I have been trying for a year now to get this down but nothing really seems to help, it is either high or it wants to die, maybe someone can give me a direction on what to try to change. WOT is almost perfect in first gear around 4800-5000 I get a little stumble but is good in second WOT. Just under WOT but over 3/4 throttle I get a little stumble in the higher rpm range 3000-4800. My second gear shifts in auto or D at 4800 in second. Additionally if anyone can take a look at the datalog and give any pointers if anything else looks odd or misconfigured as alot of you out there seem to know this system very well.
    It's all about learning, testing, changing and over and over again till good.

    CdeeZ - I have thought of going the route of upgrading the computer but my next step will be an after market throttle body system as this truck will eventually be for play and I would like to see 500hp, hopefully a year or 2 down the road. This is just a daily driver that I was looking for 350hp and hopefully still get decent gas mileage. At the present time I get around 14-15 depending on the driving situation.
    Attached Files Attached Files

  6. #6
    Fuel Injected!
    Join Date
    Feb 2013
    Location
    Euless, TX
    Posts
    2,308
    Quote Originally Posted by typhoonss View Post
    OK I have spent about 5 hours reading posts over the past 2 days and I have changed the spark table, added a little more at idle and some to the 60-100 map in the 1800-3200 range. I also added a degree to the pe so it is at 3.52 now. I also changed the BPW from 110 to 120. I took a drive and datalogged and used the vortec ve excel sheet to correct the VE tables. It did not fall on it's face in the higher rpm but still stumbled a little. So I added a little more timing higher map and rpm then took another drive. Here is where I am at now. Idle a little high, I have been trying for a year now to get this down but nothing really seems to help, it is either high or it wants to die, maybe someone can give me a direction on what to try to change. WOT is almost perfect in first gear around 4800-5000 I get a little stumble but is good in second WOT. Just under WOT but over 3/4 throttle I get a little stumble in the higher rpm range 3000-4800. My second gear shifts in auto or D at 4800 in second. Additionally if anyone can take a look at the datalog and give any pointers if anything else looks odd or misconfigured as alot of you out there seem to know this system very well.
    It's all about learning, testing, changing and over and over again till good.

    CdeeZ - I have thought of going the route of upgrading the computer but my next step will be an after market throttle body system as this truck will eventually be for play and I would like to see 500hp, hopefully a year or 2 down the road. This is just a daily driver that I was looking for 350hp and hopefully still get decent gas mileage. At the present time I get around 14-15 depending on the driving situation.
    Up your MAP AE 25% for the stumble and see if it helps. I would also do some VE tuning in the upper MAP/RPM ranges with the PE TPS enable set to about 90%. You can watch the integrator and see if it goes higher or lower than 128 to know if you are lean or rich.

    Woth that throttle body, proper fueling and timing you should have no problem reaching 5,500-6,000 rpm with that cam and heads.
    Last edited by Fast355; 03-22-2018 at 06:02 AM.

Similar Threads

  1. Replies: 6
    Last Post: 01-22-2016, 02:33 AM
  2. Z28 LT1 $EE Tuning issues
    By Terminal_Crazy in forum GM EFI Systems
    Replies: 17
    Last Post: 01-13-2016, 03:32 AM
  3. code59 tuning issues
    By Superbee in forum GM EFI Systems
    Replies: 112
    Last Post: 08-08-2015, 06:58 AM
  4. Need help. 05 chevy 1500 o2 sensor
    By JeepsAndGuns in forum Gear Heads
    Replies: 5
    Last Post: 07-06-2014, 03:11 PM
  5. 1990 chevy 2500 computer issues
    By tbitrouble in forum Introductions
    Replies: 9
    Last Post: 04-28-2014, 05:38 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •