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Old 01-24-2019, 08:26 PM   #1
98Murray
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Ways to make my bone stock 305 more reliable?

I have a bone stock '86 C10 with a 305 and all the emissions components. It is NOT a CA truck (if that makes a difference) and legally to register and inspect it it only needs safety equipment. Is there a reliability benefit to getting rid of this equipment? When I first got the truck a lot of the vacuum lines that ran to all these things were bad and I quite some time tracking down and fixing all the leaks. The trucks runs OK now aside from the non adjustable quadrajet giving me fits every now and then. I know I can drill out the plugs to access the adjusters but I am honestly just thinking about ditching the quadrajet and a lot of the emissions components for a more simple and reliable setup but, is it worth it? I mean, the truck runs ok with all of it on there and I really hate to mess with something that aint broke but at the same time I don't want it to break down on me because of this aging equipment.

Also I would like to simplify and dress up the engine bay. What are some good ways to do this? I would love to ditch the 4 belts for one serpentine belt if I could. I also have some long tube headers laying around that I may want to put on it. What are yalls thoughts??
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Old 01-24-2019, 08:53 PM   #2
Justins76
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Re: Ways to make my bone stock 305 more reliable?

I used a serpentine setup from a TBI Camaro, added an AD244 alternator along with a Lincoln MkVIII electric fan. Headers are Hedman longtubes.
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Old 01-24-2019, 08:54 PM   #3
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Re: Ways to make my bone stock 305 more reliable?

If you go with the serpentine setup make sure you get the correct water pump, they turn in the opposite direction. It also swaps position with your AC compressor and alternator. I had custom hoses made. Really cleans things up.
If you want to dump the quadrajet get a Edelbrock Performer manifold (or equivalent) so you don't have the spread bore/square bore mis-match. The Edelbrock carbs are pretty simple. I hear good things about the Street Demon but no personal experience.
Long tube headers will help breathing.
Best of all, if you decide later to do a 350 everything will work on it, too.
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Old 01-25-2019, 06:28 PM   #4
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Re: Ways to make my bone stock 305 more reliable?

Getting rid of the emissions crap won't make it more reliable per se, but it will eliminate a lot of ugly vaccum lines that eventually go bad and cause leaks.
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Old 01-25-2019, 07:21 PM   #5
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Re: Ways to make my bone stock 305 more reliable?

Get a properly remanufactured quadrajet for a 1ton smallblock if you want to keep her reliable.

Use a 70's Corvette Evap can, vacuum advance HEI, and keep your stock PCV.

Headers will not enhance reliability.

F-body 305 or 4.3l S10 Serpentine belt setup will clean up the looks.
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Old 01-25-2019, 07:46 PM   #6
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Re: Ways to make my bone stock 305 more reliable?

I second what Hatzie said. Your best bet is to get an early quadrajet from a 1-ton. Get a good re-builder and tell him you want a balance of emissions and performance. Grab yourself some manifolds from an 88-95. HEI and the simplified evap canister are a must.

If you run an open air filter buy the 6.2 air filter with the foam around it.

If you want some pep buy an RV cam and drop it in. If you really want some pep get some 305 vortec heads. Buy the Edlebrock performer intake (I have the number somewhere) and enjoy.

I am up in Canada and have gone through about 3 different engine combinations. This setup is by far the best. It runs perfectly in the cold. Feels like a stock 350 and gets great highway mileage.

In town i average 15-17 L/100km
My best on the highway has been 10.62 L/100km @120km/hr

Those numbers are with a beefed up 700r4 and 308s in the rear.
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Old 01-25-2019, 08:54 PM   #7
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Re: Ways to make my bone stock 305 more reliable?

why is a 1 ton carb better ? I have a edelbrock 600 carb and hate it, I never had troubles with m Q jet. Going to go back to a Qjet but was wondering why the 1 ton is better. I thought all Q jets were the same, don,t know but asking
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Old 01-26-2019, 12:05 AM   #8
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Re: Ways to make my bone stock 305 more reliable?

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why is a 1 ton carb better ? I have a edelbrock 600 carb and hate it, I never had troubles with m Q jet. Going to go back to a Qjet but was wondering why the 1 ton is better. I thought all Q jets were the same, don,t know but asking
I had an edelbrock for years an way plagued with starting issues and constant pinging no matter what I did with the timing. I tried the whole 9-yards with it. when I pulled apart the last motor it had washed the rings so bad you could stick a dime under the ring ridge.

The 1-ton quadrajets give you a bigger CFM flow without having to modify anything. If you are good with fiddling with jets you can get it set up how you want. Otherwise get someone to build it.

Regardless make sure all the bushings are good. The quads will actually leak around the bushings and act like you have a vacuum leak. Also ensure to avoid any of the late computer controlled or bio-quadrajets with all the junk on them.

Alternatively you can buy the 1900 series edelbrock carbs. they are basically a quadrajet but have a crazy price tag.

And yes essentially the quadrajets are the same. the CFM flow differences can be fixed by bending a tab out of the way. But the Pontiac, Buick and GMC carbs have a different fuel inlet (GM turns vs. Pontiac straight). And as I mentioned some of the later years have some emissions junk on them...avoid those.

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Old 01-26-2019, 11:51 AM   #9
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Re: Ways to make my bone stock 305 more reliable?

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why is a 1 ton carb better ? I have a edelbrock 600 carb and hate it, I never had troubles with m Q jet. Going to go back to a Qjet but was wondering why the 1 ton is better. I thought all Q jets were the same, don,t know but asking
The 1 ton wasn't an electronic carb and had a lot less crap on it because it was in a different emissions class.
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Old 01-26-2019, 09:05 PM   #10
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Re: Ways to make my bone stock 305 more reliable?

Lots of good info yall! Thanks! What about Holley carbs? And, has anyone messed with EFI?
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Old 01-26-2019, 10:57 PM   #11
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Re: Ways to make my bone stock 305 more reliable?

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Lots of good info yall! Thanks! What about Holley carbs? And, has anyone messed with EFI?
YES. Avoid the latest "self-learning TBI junk!" I just went through a nightmare with a Holley Sniper. Huge POS. The Edelbrock Pro-flo is a true fuel injection (port) system that worked great for me previously.
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Old 01-26-2019, 11:19 PM   #12
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Re: Ways to make my bone stock 305 more reliable?

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Lots of good info yall! Thanks! What about Holley carbs? And, has anyone messed with EFI?
I've done quite a bit of research into using factory fuel injection systems. I'm going to swap in a TBI from a 1987 along with repining the harness to use the 94/5 PCM. Cheap, reliable, looks stock, simple and parts are available everywhere for the few sensors needed since its factory GM. The OBDI stuff uses PROM chips. If you planing for engine mods, you'll need to burn your own chips, but then any EFI system will need to be properly tuned when retrofitted.
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Old 01-26-2019, 11:24 PM   #13
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Re: Ways to make my bone stock 305 more reliable?

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Originally Posted by 85gmcguy View Post
If you go with the serpentine setup make sure you get the correct water pump, they turn in the opposite direction.
Also clutch fan since is will be turning backwards as well, or go electric.
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Old 01-27-2019, 12:42 AM   #14
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Re: Ways to make my bone stock 305 more reliable?

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Originally Posted by 98Murray View Post
Lots of good info yall! Thanks! What about Holley carbs? And, has anyone messed with EFI?
Holley carbs are fussy to setup and doing it right takes some experience. If you have said experience then go for it.
Rochester Quadrajets just work and keep right on working for a long time. My guess is your 1986 Rochester is probably the original or the first reman.
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Old 01-27-2019, 12:09 PM   #15
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Re: Ways to make my bone stock 305 more reliable?

I rebuilt a 77 305 for my '70 LWB. Used a 68 q-jet iron manifold, stock cam for a late 60's truck 327/350, and a late 70's Buick rejetted q-jet with electric choke. It has been a good running stock-performance engine and only maintenance is fluid changes. Have 120k miles now since rebuilding.
305 has a reputation as a dog, but take the emissions crap off and set it up like an older small block it does well.
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Old 01-30-2019, 12:47 AM   #16
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Re: Ways to make my bone stock 305 more reliable?

I also have an 86 GMC with a 305 with all the emissions that runs great now. I had my QJet rebuilt by a person that all he does is rebuilt all kinds of carbs. I asked him if he could get me an older QJet without the electrical attachment on the front of the carb. He said that he would disable this inside the carb and fix it so that instead of feeding one side of the primaries he would make it feed both on acceleration. I now have the 2 wires that were connected to the front of the carb now just lying to the side. The truck really has more power on acceleration. He also removed the plugs that covered the adjustment screws and with a vacuum gauge I have the engine running very smooth!
From what he said and several other friends in the repair business they all claim the QJet is one of the best carb out there. One of these days I may remove the emissions on my truck but I want to keep it as original as I can right now. Plus I live in Texas and we have to pass a visual inspection of original parts. It is running great right now!

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Old 01-30-2019, 01:29 PM   #17
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Re: Ways to make my bone stock 305 more reliable?

Watching this one with interest.

My 83 with a 305 runs smoothly, but has crap for power. Truck only has about 38K on it and it sat up for a long time before I dragged it out and got it running. Had the carb rebuilt by a local shop, along with new plugs and wires, and I later removed some of the smog stuff.

Starts fine, idles fine, runs smoothly, but just doesn't have any guts. I know the 305's aren't powerhouses but this one is a dog.

I've wondered if my timing should be adjusted, or if perhaps the carb needed adjustment, but yall are saying these carbs are blocked off so they can't be adjusted?

I run Motorcraft 2100s on my Jeeps. Cheap, simple to tune, and reliable. Factory BBD's on the Jeep 258's had stepper motors that were computer controlled and were garbage, so I junked them and went to the MC2100's. I know nothing about GM carbs.

I don't drive the truck much, so it tends to get mothballed until I need to haul something, which leads to me not troubleshooting the lack of power.

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Old 01-30-2019, 02:04 PM   #18
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Re: Ways to make my bone stock 305 more reliable?

I put Summit's K1101 cam in my stock LE9 305. Still had the ESC HEI. It had great power and got 16 MPG in this K10. Even pulled a good hill in overdrive with 3.08 gears. For reliability, I'd rebuild the carb, give it fresh fluids, replace the ignition components, and set the timing.
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Old 02-02-2019, 03:52 PM   #19
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Re: Ways to make my bone stock 305 more reliable?

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I put Summit's K1101 cam in my stock LE9 305. Still had the ESC HEI. It had great power and got 16 MPG in this K10. Even pulled a good hill in overdrive with 3.08 gears. For reliability, I'd rebuild the carb, give it fresh fluids, replace the ignition components, and set the timing.
This right here^

If you have an LE9 305, then you have a good motor. Many people confuse the electronically controlled carburetor and distributor for emissions equipment. It is actually a high-compression engine to help make up for it smaller size. The ESC is to control engine knock under load by retarding timing. The one I have runs surprisingly well with unexpected power. If you have an air pump, I would pull that. And I would research any other emissions components you want to remove. I will be leaving the ESC intact. If you run mid-grade gas or better, or a octane booster you may keep the ESC from retarding your timing under load, and notice a little increased power.
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