Search results

  1. Jims86

    350 TBI 2k-3k RPM woes

    Easiest way to accellerate the diagnosis process if there is a problem, is to get an ALDL cable and datalog a long drive, and see what the ECM is seeing.
  2. Jims86

    carb suggestions for a 350

    The setting of the vacuum brake on the secondary side is mostly what determins the CFM...Up to 750 wide open....not sure how low it can go, never worried about it. I have seen Q jets on 4.3 v6s in boats though. Maybe they can go down 550 or below. Very Versital carb, but yes, a little...
  3. Jims86

    carb suggestions for a 350

    Q Jets are mostly 750, but there is an 800cfm model from the late 60's Pontiac, Olds, and Buick muscle cars...pretty rare piece. it can be identified by humps in the primary barrels. 750s are 750s, there is no making them bigger. The big issue with Edelbrocks is the poor bowl design...Hard...
  4. Jims86

    carb suggestions for a 350

    750 is what came on gm 305s, 350's and 454s from the factory. Just have to make sure it's jetted/ rodded correctly. I would go with that Holley, get a rebuild kit. While your at it, call holley and ask for the recommended jetting size...I think after all is said and done, you will still be...
  5. Jims86

    TBI or carb questions

    Financially...best is to stay with TBI, do a stock rebuild. put 1.7 exhaust valves in the TBI heads, and port the exhaust side a little....that is if you have the ability to do the headwork. Stock cam should do fine, as well as anL31 cam, but you would have to convert to roller, which is at...
  6. Jims86

    Exhaust system options

    Probably walker....may see a little dip in takeoff power by going bigger, but not much with another1/4inch. Best thing is to go as small as possible and use a wide open muffler.
  7. Jims86

    carb suggestions for a 350

    Those people are generally the lazy type(not everyone, so I dont want to hear any shit) and wont bother to learn about the q-jet. Its easier for them to just go to oriellies and plunk down $300 or so for a carb of inferior design. Q jets, and Holley are best. around 750 cfm is perfect for a...
  8. Jims86

    TBI or carb questions

    Chris has had some gremlins show up with his TBI, but if yours is running fine, keep it if you want. you will need an older manifold style for the heads, most of those pre 87 factory heads were 74cc. The 87 heads are an improvement over the earlier, but Vortec heads would be my...
  9. Jims86

    TBI or carb questions

    Good choice on carbs, stay away from Edelbrock. Dual plane manifold is the way to go, single is for much higher rpm ranges. IMO, 1300 is a tad high for power to come in for a truck. I suggest you take a look at the stock vortec L31 roller cam, as well as the HT383 cam from gmpp. if you dont...
  10. Jims86

    1987 Silverado Fuel problem

    First, and cheapest...check the fuse marked ECM B
  11. Jims86

    TBI or carb questions

    If you are going to do a lot of off road, you would be better off doing a stock rebuild, with the stock cam. TBI will not respond well to a cam thats too far from stock. You would be better off with rebuilding the 4 bolt bottom end, and using the heads and intake from the TBI engine....Those...
  12. Jims86

    Talk me into or out of TBI

    Beginning to wonder if these TBI problems aren't because of electrically worn out injectors. I am soo outa practice....That was one of my reasons for switching backwards from TPI, was to see if I could find what the issue is behind all these headachs.
  13. Jims86

    Talk me into or out of TBI

    Hi Honey!
  14. Jims86

    HRPC--Skip White Distributor

    I have the TBI one. Excellent piece.
  15. Jims86

    Gasket for EFE "butterfly" valve in exhaust?

    Price wise, thats about as reasonable as it gets. If all else fails trying to find a gasket, I have had luck making them wire mesh, carfully covered in heavy foil, or just goop it with ultra copper RTV.
  16. Jims86

    Talk me into or out of TBI

    Sounds like you may have some slight adjustments with the MSD, but its running good. TBI will yeild reliability for a daily driver, that does no need much attention, but will also be a bit on the slow side, compaired to what makes you smile now. This is due to the lower 450ish cfm tBi...
  17. Jims86

    Wiring harness question

    Good deal, thats exactly what I was going to suggest.
  18. Jims86

    Wiring harness question

    Sounds like he is talking about the TPS....it may be the round style plug. there is a slim chance it has the later IAC too. there really is no way to tell by year. For some reason they put the newer stuff on some, and the older stuff on others.
  19. Jims86

    4.3 v-6:

    Yup, that one is steel tube. Like the 85-85 3/4 ton 350 manifolds...they breathe a little better. Weld her up! But make sure you dont need it to pass inspection first.
  20. Jims86

    Wiring harness question

    No reason to change the harness just to install the 350. Just swap the ecM, as there are different chips for the 350 and 305. The oil pressure sender on the 350 should be behind and to the drivers side of the distributor, tapped in with the oil pressure switch for the fuel pump.
  21. Jims86

    Wiring harness question

    No,i meant an SB TBI truck. 86 and down are not worth messing with to incorporate an EFI harness, just run it stand alone. The 86 and earlier harnesses pretty much only handle the charging system. In the OP's case, he is just swapping an 87 305 for a 91 sub 350. only difference is the ecm engine...
  22. Jims86

    Wiring harness question

    Harnesses are different between the 91 gMT400 1/2,-3/4 ton and Squarebodies, and unless the 91 burb, whitch is still square, is a 3/4 or 1 ton with a THM-r2(early 4l80 E) the TBI hanesses and ECMs are the same. And the only difeerence is really the harness length,mbecaus they routed the GMT 400...
  23. Jims86

    Wiring harness question

    And that alt and AC wiring is the only thing you need to modify. No need to move harnesses from one square body to another. Use the EcM from the burb, it will plug right into the 87 harness.
  24. Jims86

    1990 5.7L TBI Flooding at Freezing Temps on Cold Start?

    Yeah, it could. Take enough power to crank the starter, and you wont get a hot enough spark. But cracking the throttle open to start makes no sense. I know its cold, but maybe hook up a known good battery and jump it....If it works, get a batt tray for the drivers side, and run doubles.
  25. Jims86

    '88 TBI 350 - multiple personalities

    Love it! a mini tour bus! What do you play? I am doing the band thing meself here...Drums.

Latest posts

Forum statistics

Threads
44,422
Posts
957,412
Members
36,769
Latest member
Bowtie72
Top