Page 6 of 7 FirstFirst 1234567 LastLast
Results 76 to 90 of 98

Thread: 94 Z71 TBI on vortec build runs richer than a crooked politician!

  1. #76
    Fuel Injected! S.O.B.B.'s Avatar
    Join Date
    Nov 2017
    Location
    Ontario Canada
    Posts
    167
    One would think if u have a intake leak to the crank case it would suck oil in.if u disconnect vacuum and breather for pcv u shouldn't still have tons of vacuum at the pcv hole or oil fill cap hole.u have smoke tester to see if it still sucks in a lot.if it does maybe there is a leak.but one would think that would cause a lot of symptoms.just a thought.
    Jeeper
    87 sjimmy powered by a 92 cadillac 4.9L pfi on 7427pcm /700r4/ 8.8 3.55 rear/disc brakes.

  2. #77
    Fuel Injected! Jimmie's Avatar
    Join Date
    Oct 2018
    Posts
    69
    when I first installed the engine it was running rich but after replacing the 18lb fuel pressure spring with the stock one because it was running at 20 pounds with the 18 pound spring and now 13 with the stock it fixed the rich idle, but now I'm wondering if I should try another spring because every time I stomp the gas it go's lean on the wide band AF gauge also every time it upshifts it go's lean instantly like 18 lean and sometimes off the gauge lean, these last few days being in the 20's coming to work it backfires through the intake when it shifts gears and go's lean or if you gas on it to take off cough pop lean then back to 12 or 13 and it takes off again. The guy I bought the chip from who has been trying to help fix the bin said that he put more "accelerator pump" AE on my bin than any small block he has tuned, could this be from lack of fuel pressure or should the 13 pounds be ok. thinking of it like a carb I would give it more fuel, maybe I've been over thinking this whole thing and looking for gremlins everywhere else. any thoughts? hey Fast 355, I'll be in your area soon "Denton" maybe I could swing by and let you take it for a spin and get your thoughts on it? as always any ideas are greatly appreciated.

  3. #78
    Fuel Injected! Jimmie's Avatar
    Join Date
    Oct 2018
    Posts
    69
    timing glitch lean.jpg

    here's something to odd to look at, the green row is my timing advance, next is rpm, blue is throttle position, yellow is my wide band AFR, it has a glitch that when rpm is below900 or so it gives 23039 or so degrees advance. Also it leans out more when this happens, this is the type of crazy I'm trying to figure out here, and yes all of my grounds are new and well grounded, replaced ign module, cap rotor wires coil, everything on this thing is new. Dave, have you ever seen this before??

  4. #79
    Fuel Injected!
    Join Date
    Jan 2017
    Posts
    411
    I would think that you probably could get away with the higher spring pressure and then you need to do this: http://www.gearhead-efi.com/Fuel-Inj...-data-Tutorial! All VEs need to be adjusted to return BLMs of approximately 128.

    Getting ahead of myself, DO THIS prior to dialing in BLMs...if you go with the higher spring rate, I would use a fuel injector calculator like the one at Witch Hunter and calculate what your lbs-hr will be. Once you've determined that, you need to adjust that in the scalars lbs-hr.
    Last edited by stew86MCSS396; 03-07-2019 at 03:27 AM.

  5. #80
    Fuel Injected!
    Join Date
    Feb 2013
    Location
    Euless, TX
    Posts
    2,308
    Quote Originally Posted by Jimmie View Post
    when I first installed the engine it was running rich but after replacing the 18lb fuel pressure spring with the stock one because it was running at 20 pounds with the 18 pound spring and now 13 with the stock it fixed the rich idle, but now I'm wondering if I should try another spring because every time I stomp the gas it go's lean on the wide band AF gauge also every time it upshifts it go's lean instantly like 18 lean and sometimes off the gauge lean, these last few days being in the 20's coming to work it backfires through the intake when it shifts gears and go's lean or if you gas on it to take off cough pop lean then back to 12 or 13 and it takes off again. The guy I bought the chip from who has been trying to help fix the bin said that he put more "accelerator pump" AE on my bin than any small block he has tuned, could this be from lack of fuel pressure or should the 13 pounds be ok. thinking of it like a carb I would give it more fuel, maybe I've been over thinking this whole thing and looking for gremlins everywhere else. any thoughts? hey Fast 355, I'll be in your area soon "Denton" maybe I could swing by and let you take it for a spin and get your thoughts on it? as always any ideas are greatly appreciated.
    I am not even an hour south of Denton. I don't get many days off work but if the time overlaps some off time I definately do not mind looking at it. I still have my AutoProm.

    You definately need the 20 psi spring and at high rpm and WOT with your engine build that may still not be enough fuel. The last TBI I messed with of similar specs had the 28-30 psi spring in it and still hit 80% duty cycle. Figure that engine was 360-380 hp at the crank.

    My last personal engine had 3x a stock 454 when it came to AE. You have to think of it in terms of airflow and plenum volume in the manifold. A stock 230 hp 454 is not breathing nearly as well as a 350+ HP small block. It is also harder to keep fuel in suspension on a throttle stab with an unheated intake manifold. It is the reason those high rise air gap manifolds generally reapond best with a double pumper. LOTS of pumpshot.
    Last edited by Fast355; 03-07-2019 at 04:51 AM.

  6. #81
    Fuel Injected!
    Join Date
    Feb 2013
    Location
    Euless, TX
    Posts
    2,308
    The AutoProm is pretty cool though. I can real time tune and datalog with the engine running down the road. With data tracing enabled you can also tell exactly where the engine is operating in a given table at a given operating condition.
    Attached Images Attached Images

  7. #82
    Fuel Injected! woody80z28's Avatar
    Join Date
    Nov 2011
    Location
    Walton, NY
    Age
    38
    Posts
    242
    Quote Originally Posted by Fast355 View Post
    The AutoProm is pretty cool though. I can real time tune and datalog with the engine running down the road. With data tracing enabled you can also tell exactly where the engine is operating in a given table at a given operating condition.
    I just enabled data tracing and the 0-5v wideband logging on my car last year and took another stab at the tune (with a new cam and heads). Made a huge difference in dialing it in. I'm looking forward to doing that with my new TBI to MPFI project on the truck. The truck is my winter beater, and even with a ton of AE it would bog a little when rowing gears.
    80 Camaro Z28 - 550hp AFR 383 / T56 6spd (Holley HP EFI)
    91 Beretta "SS" - 260hp 3400 MPFI / HM282 5spd (7730/$A1) sold! for crazy money...but I miss it
    94 Silverado Z71 - 300hp Vortec 357 TBI / NV4500 5spd (7427/$0D) gone but not forgotten
    96 Beretta "T56" - 4.8 LS RWD swap / 6spd (0411/2156)
    01 Silverado 2500HD - stock Vortec 8.1 / ZF6 6spd (0411/8322)
    https://www.youtube.com/c/GEARHEADdezign

  8. #83
    Fuel Injected!
    Join Date
    Jan 2017
    Posts
    411
    OP owns an Ostrich...just sayin.

  9. #84
    Fuel Injected! Jimmie's Avatar
    Join Date
    Oct 2018
    Posts
    69
    wot inj duty cycle.jpg

    Thanks for the quick replies and good info! I will have to look into the data tracing, I'm not sure how that works. Here's another odd screenshot of the same datalog,noticethe injector duty cycle "in red to the left" at wot in the 40% range? this thing is making no sense to me. I have been letting the guy who burned my initial chip try and fix I t just because I paid $300 for it but it looks like I need to just finish learning how to tune these TBI engines myself and get it done. I will read the links supplied and get back on datal logging. let me know what y'all think on this duty cycle being low, seems like it should be a lot higher rite? I bought new ac delco injectors that are supposed to be stock for a 350, maybe they sent ones for a 454? Fast355 I will let you know ahead of time when I am going to be over your direction, will be in Argyle actually down from lantana. Again thanks for all the replied, any and all help is very greatly appreciated!!!
    Last edited by Jimmie; 03-07-2019 at 04:58 PM.

  10. #85
    Fuel Injected! Jimmie's Avatar
    Join Date
    Oct 2018
    Posts
    69
    Quote Originally Posted by woody80z28 View Post
    I just enabled data tracing and the 0-5v wideband logging on my car last year and took another stab at the tune (with a new cam and heads). Made a huge difference in dialing it in. I'm looking forward to doing that with my new TBI to MPFI project on the truck. The truck is my winter beater, and even with a ton of AE it would bog a little when rowing gears.
    I thought about doing a TBI to MPFI on my truck, I loved my old TPI but hate the price of the lower intake for the vortec heads. what type of setup are you going with?

  11. #86
    Fuel Injected! Jimmie's Avatar
    Join Date
    Oct 2018
    Posts
    69
    Quote Originally Posted by Fast355 View Post
    The AutoProm is pretty cool though. I can real time tune and datalog with the engine running down the road. With data tracing enabled you can also tell exactly where the engine is operating in a given table at a given operating condition.
    I just did a search on data tracing on here and can't seem to find a good tutorial on it, maybe I'm searching the wrong place? I have the ostrich so I should be able to do it with that rite?

  12. #87
    Fuel Injected!
    Join Date
    Dec 2012
    Location
    Naches, WA
    Age
    76
    Posts
    64
    Quote Originally Posted by Jimmie View Post
    I just did a search on data tracing on here and can't seem to find a good tutorial on it, maybe I'm searching the wrong place? I have the ostrich so I should be able to do it with that rite?
    With Tunerpro try this.

    http://www.gearhead-efi.com/Fuel-Inj...unerPro-How-To!

  13. #88
    Fuel Injected!
    Join Date
    Feb 2013
    Location
    Euless, TX
    Posts
    2,308
    Quote Originally Posted by Jimmie View Post
    I thought about doing a TBI to MPFI on my truck, I loved my old TPI but hate the price of the lower intake for the vortec heads. what type of setup are you going with?
    If you are patient you can find alternatives. I found a brand new Indimar tunnel ram MPI intake for Vortec heads for $500. The new Indimar returnless fuel rail was $180 from Michigan Motor Sports marine. It uses a TPI/LT1 style throttle body. I will probably have Lloyd Elliot port this to match the Assault Racing heads he ported for me too. Should make a good bit more torque than a single plane, ramjet, or miniram style intake but still breathe very well up the rpm range. I like the intake runner/plenum design better in this manifold than the Holley stealthram as well.
    Attached Images Attached Images
    Last edited by Fast355; 03-07-2019 at 07:41 PM.

  14. #89
    Fuel Injected! woody80z28's Avatar
    Join Date
    Nov 2011
    Location
    Walton, NY
    Age
    38
    Posts
    242
    Quote Originally Posted by Jimmie View Post
    I thought about doing a TBI to MPFI on my truck, I loved my old TPI but hate the price of the lower intake for the vortec heads. what type of setup are you going with?
    I bought injector bungs on ebay for $30 and a fuel rail for $80 and I'm gonna use the TBI TB (with no injectors) and drill and weld the bungs in my Vortec Performer carb manifold. I have a steel carb to TBI adapter plate that I'm gonna weld the fuel rail mounts to and it should all be pretty low buck.

    Here it was on the initial TBI build in 2011.
    80 Camaro Z28 - 550hp AFR 383 / T56 6spd (Holley HP EFI)
    91 Beretta "SS" - 260hp 3400 MPFI / HM282 5spd (7730/$A1) sold! for crazy money...but I miss it
    94 Silverado Z71 - 300hp Vortec 357 TBI / NV4500 5spd (7427/$0D) gone but not forgotten
    96 Beretta "T56" - 4.8 LS RWD swap / 6spd (0411/2156)
    01 Silverado 2500HD - stock Vortec 8.1 / ZF6 6spd (0411/8322)
    https://www.youtube.com/c/GEARHEADdezign

  15. #90
    Fuel Injected! Jimmie's Avatar
    Join Date
    Oct 2018
    Posts
    69
    Quote Originally Posted by Fast355 View Post
    If you are patient you can find alternatives. I found a brand new Indimar tunnel ram MPI intake for Vortec heads for $500. The new Indimar returnless fuel rail was $180 from Michigan Motor Sports marine. It uses a TPI/LT1 style throttle body. I will probably have Lloyd Elliot port this to match the Assault Racing heads he ported for me too. Should make a good bit more torque than a single plane, ramjet, or miniram style intake but still breathe very well up the rpm range. I like the intake runner/plenum design better in this manifold than the Holley stealthram as well.
    I would love to find a deal like that, got a little drool on my laptop looking at it!!!!!!!! That is definitely more my style!!

Similar Threads

  1. 5.7 vortec runs rich
    By dhworkin in forum GM EFI Systems
    Replies: 20
    Last Post: 05-14-2017, 09:17 PM
  2. Replies: 14
    Last Post: 03-17-2016, 01:04 AM
  3. Replies: 119
    Last Post: 01-03-2015, 10:17 PM
  4. Getting ready to start my tbi vortec build.
    By bgwhtahoe in forum GM EFI Systems
    Replies: 10
    Last Post: 05-01-2014, 04:47 AM
  5. S10 Vortec 5.7L build in hex
    By Caleditor in forum OBDII Tuning
    Replies: 26
    Last Post: 01-24-2014, 09:34 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
  •