Search results

  1. 1987 GMC Jimmy

    Upgrading brakes on 84 K10

    That might be worth considering. It boils down to you looking at how much interface between the pads and rotors is occurring and deciding whether or not you’re satisfied with it. The fronts do approximately 70% of the braking, which is why it’s been the industry standard for 55-ish years to have...
  2. 1987 GMC Jimmy

    Chevy 350 light knock

  3. 1987 GMC Jimmy

    Upgrading brakes on 84 K10

    It depends on how much you want to spend. The gold standard for brake upgrades is going with rear discs, but I don’t think that would ever be necessary even hauling the box full volume, high mass or keeping the trailers at or below 5K pounds gross. If you hauled a 5000 pound trailer, I think the...
  4. 1987 GMC Jimmy

    90-91 gauge cluster

    Right, and that’s what I meant. According to my math, it’d take 85 days without stop of burying the speedo needle at 90 mph with a drill to reflect my actual mileage starting from zero miles. Ain’t gonna happen. Even a used one would have to be relatively close for that approach to be feasible...
  5. 1987 GMC Jimmy

    1983 K20 350 SBC Upgrade Opinions

    To answer your question to me, you’ll need to upgrade valve springs if you go with that cam. If you go with one that’s below the Vortec stock spring .450 lift threshold, you can keep what’s on there. The cam you posted was like .447/.452 so even though it’s flirting with that ceiling, I’d still...
  6. 1987 GMC Jimmy

    90-91 gauge cluster

    Thank you. If I see any junker squares of that year, I know what to get. I might even get away with adding/subtracting mileage with a drill.
  7. 1987 GMC Jimmy

    What is this?

    Vacuum advance so I guess that is a vacuum tree. The other nipple should be going to something, maybe a transmission modulator, HVAC mode control, or cruise servo. If there’s nothing missing, it needs to be capped off because that represents a pretty significant vacuum leak.
  8. 1987 GMC Jimmy

    What is this?

    It looks like a regular ole vacuum tree or maybe a valve, but I lean towards the former. @CorvairGeek
  9. 1987 GMC Jimmy

    Cummins 6BT swap in a V2500 Suburban?

    Good advice above. If I was doing this swap, I’d also go for an 89-91 to keep it VE44 w/o intercooler. I wouldn’t go past ‘93. It’s still a fairly powerful motor, and you can tune on it a little bit to improve the stock specs. This version is the true nexus of simplicity and a torquemonster...
  10. 1987 GMC Jimmy

    90-91 gauge cluster

    Thanks, I had no idea they had them! I’ll have to add that to my wishlist. And yours is an ‘85? I figured it’d be 1989-early 90 if they did because I’ve seen ‘88s with the trip odometer and those still had hundred thousand mile odometers.
  11. 1987 GMC Jimmy

    Misterious Shimmy 45-55mph OD

    I was thinking the same with the lockup, although the shimmy is front to back, not side to side, and there should be a distinct chattering sound. I’ve had the same problem with one for years. I put some of that Instant Shudder Fixx in the transmission, and it helped a lot. Mine was real bad so I...
  12. 1987 GMC Jimmy

    90-91 gauge cluster

    I wish they put a six integer odometer (XXXXXX.X) in these, I’m fine with the mechanical speedo and Hall effect VSS. That’s the main appeal to me with one like this. Does anyone know if they offered the million mile ones before the electronic switchover?
  13. 1987 GMC Jimmy

    Rear end

    Cheapest is going to be a junkyard G80 Gov-Lok, and that will be an diff. explosion waiting in the wings. You’ll almost certainly have to spend more to reap the benefits. I like the idea of the TrueTrac if you do anticipate frequent practical use if not daily driving, errands, lots of light...
  14. 1987 GMC Jimmy

    Excess Rear End Backlash

    If you could, do a rough check of the pinion slop up-down/side-side (rotational play irrelevant to this test) on the driveshaft side of the pumpkin. My guess is you might find it to be sloppy. It sounds like you may still have the cover off so if you can, take some good pics of the ring and...
  15. 1987 GMC Jimmy

    Sludge In Coolant System

    I would pull the thermostat and tee in a flush kit to the heater hose and backflush the system. They sell the little kits at Walmart. Once the water’s blowing out clear, I would run a cleaning substance in the system. Some people use CLR/Zep or white vinegar. All good stuff, but they’re strong...
  16. 1987 GMC Jimmy

    1983 K20 350 SBC Upgrade Opinions

    The cam seems like a solid choice, although you’d need to add valve springs to the list for that model. Those lift specs are right on the edge of the ceiling for Vortec Springs so I’d rather knock that out rather than playing chicken with the ones you have. Plus, Comp recommends it with that cam...
  17. 1987 GMC Jimmy

    83 K5 bodywork

    Very nice indeed!
  18. 1987 GMC Jimmy

    Compressor fittings dont fit

    If I may jump in, it depends whether you have an R4 “pancake” or A6 (longer) compressor. The perimeter-design, radial R4 is an inferior design to just about anything: noisy, less efficient, poorly compatible with rebuilding due to how it wears internally. New units, if you get a good one, are...
  19. 1987 GMC Jimmy

    Pouring Gas from Carb

    I agree with the assessments above, but if you’re nearing or past 200K miles, I’d do the standard workup on it. Well plugs sealed, primary throttle shaft bushing, rebuild. The bushing requires a press, which you may have to outsource that service, but the rest is DIY-friendly. If you have...
  20. 1987 GMC Jimmy

    New radiator suggestions?

    I would seek to keep/repair the brass-cuprous unit as a first option and maybe look into the Champion as a secondary option. Plastic incorporated radiators are cheap and ubiquitous, and you can repair them yourself to extend their lives some if you want, but they’re more of an interval...
  21. 1987 GMC Jimmy

    Brass radiators - what would you pay to repair vs replace and what can be repaired

    Maintenance, or at least not letting it go to hell, on the front end is key. Hard municipal/rural waters, coolant corrosion inhibitor breakdown with age/use, and improper coolant to water ratio are the reasons good Harrison style units go to radiator heaven, not from a lack of quality. You can...
  22. 1987 GMC Jimmy

    Help! Carburetor on 250 I-6

    I’ve bought from them before, possibly several times, can’t remember what. Good idea, I’ll have to check.
  23. 1987 GMC Jimmy

    Help! Carburetor on 250 I-6

    According to the interchange I saw it’s: BUICK REGAL 1988-1991 CHEVROLET LUMINA 1990 OLDSMOBILE CUTLASS CRUISER 1988 OLDSMOBILE CUTLASS SUPREME 1988-1990 PONTIAC 6000 1990 PONTIAC BONNEVILLE 1988 PONTIAC GRAND PRIX 1988-1990 Not many years or models, which I think the third leg was just a...
  24. 1987 GMC Jimmy

    Help! Carburetor on 250 I-6

    Agree 100% with the caveat on MPFI being my experience with GM 60* V6 injectors, they can be flaky once they get to a certain age, and I’ve also heard bad things about the Gen I spider system, but that once they were upgraded to the Gen III, LS-based style, they were perfect. My Jimmy will set...
  25. 1987 GMC Jimmy

    Help! Carburetor on 250 I-6

    Actually, you’re probably thinking of an SM465. It’s technically a four speed, but one of those is “Granny Low” with three street gears, no overdrive. The NP833 is somewhere between the Saginaw Three and the SM465 in toughness, and the 465 is tougher than an NV3500. The 833s were more common in...

Latest posts

Forum statistics

Threads
44,163
Posts
950,686
Members
36,276
Latest member
2manysquares2care
Top