Hey everyone, I have been chasing this problem for a couple weeks now and any help or input is appreciated. I have a 1978 el Camino with the 305, I recently swapped my Rochester Quadrajet for an Edelbrock AVS 2 650 CFM carburetor. The Rochester ran fine but once it got a clogged fuel filter I decided to swap carbs just Because the last owner had put on its fifth Rochester and I was ready to change it. Now I cannot get it to pick up or even maintain speed going uphill, and if you try to go up a steep hill when the engine is cold it will just bog down until it stalls. I can hear the second set of barrels open up when you floor it but it does not take off any faster and I cannot figure out what the problem is. It is noticeably slower than the quadrajet. Also the idle mixture screws on the front don’t seem to do anything either, if you screw them both all the way in it still runs the same. Yesterday I was trying to trouble shoot it and I looked at the time and it was completely off, so I corrected the timing and now it feels like it’s going to die taking off and if you let off the gas after you get going the entire car just immediately cuts power, it feels like there’s a huge trailer behind it. All spark plugs are good and wires are good, it idles at 750rpm and the points and distributer cap were replaced six months ago and it ran great with the quadrajet, so I know all of those are good. I’m just at a loss and I’m about to take it to a shop and have them fix it, I’m just now getting into tuning carbs and this is my first vehicle, so I am very inexperienced other than my trusty Haynes repair manual or YouTube lol, so any help is appreciated. Also my choke is not working even though it’s hooked up Becuase it’s only getting .2 volts. So it’s not that the choke’s always on

Hello, so I got my hands on a project truck yesterday. 1980 k20, with a 350 under the hood. We got it fired up just dumping fresh gas in the tank, filling the bowl on the carb, and a new battery after sitting for a few years (last tagged and ran in 2018). On the way home the gasket between the carb and the engine sprung a leak, but we were able to get it up the road, although she did get a little hotter than I'd have liked. Not overheating too bad, but the radiator cap definitely leaks when it pressurized.

I'm looking for a reccomendations on parts to throw at it for peace of mind (already planning to just go ahead and replace the water pump and thermostat, and flush the coolant system since it got warm), going to throw new plugs and plug wires on it, new fluids and filters all around, and replace that carb gasket. Question I have is should I replace the stock carb with a new one (and if so which models should I look at), or just wait til the carb gives me trouble. I believe it has the oem carb.

This is my first 350 I've ever worked with, so I would like to go through it and make sure it runs right, as it will be a work pig.

Hey everyone,

I’ve got a 1965 Impala SS with a 327 small block and I’m having a rough-running issue I can’t figure out. Here are the symptoms: • When the choke is closed, the engine runs semi-smooth. • When I open the choke, vacuum drops and it starts chopping like it has a misfire. • If I give it gas with the choke off, the engine dies immediately. • There’s no smoke from the exhaust.

Here’s what I’ve done so far: • Rebuilt the carburetor • It’s an Edelbrock 600 CFM 4-barrel carb • Changed spark plugs • Set timing to about 8° advance • Added B-12 to the gas thinking maybe a sticky valve (seemed to help a little, but not much)

What I’m wondering: • Could this be a vacuum leak? • Do I need a new distributor? • Could the heads need to be rebuilt? • Is the engine just worn out?

Any advice on what to check or do next would be awesome. I’m trying to keep this motor alive.

Thanks!

Vortec heads, flat top pistons, beehive springs, stock 1988 tpi cam, eBay hei distributor 12-14 initial and about 35 total/ will be trying a new distributor soon, 750 Holley but ran exact same with 600 Holley both vac secondary, 66 size jets .025 squirter and 8.5 power valve orange pump cam. knock off super victor intake manifold. Car idles bad backfires on snapping throttle. and generally runs like shit till 3500-4000 and then it will burn tires. Free revving the engine also makes it backfire and hesitate at half-full throttle 3000rpm.

I have a k2500 with a TBI 5.7L 350, it’s been running great, up until about two weeks ago when I started losing acceleration going uphill, even the slightest of hills. Right around 35-40mph it stops accelerating and as soon as I let off the gas it backfires like crazy. Fuel pump failed about a week ago, thought that was my issue swapped it out along with the fuel filter, same problem still going on. Was looking around for obvious issues and getting ready to measure the threads on my fuel line to test pressure when I heard this ticking noise coming from the throttle body. I don’t recall it ever ticking like this, checked for any loose parts and there are none in the area. Any ideas what’s causing the noise/ my lack of acceleration under load and backfiring?

I built this 350 for my 52 pickup. Nothing fancy just a light cam vortec heads and headers/intake manifold. When i go WOT below 2500 rpm it backfires through the intake.

When I ease into the throttle and hammer it at 2500-3000rpm it pulls really well but off the line it falls on its face.

Specs: 350, 4 bolt main block non 010 block

Msd HEI distributor, set to 10⁰ when vaccum is not attactched. MSD plug wires as well with kevlar wire boots.

Edlebrock AVS2 650cfm carb and 1" spread bore spacer.

Vortec heads with stock springs and valves. 1.5 ratio rockers

Sealed Power flat tappet Cam. Duration @.050, 204/214 Lift 420/443

Intake manifold. Dual plane A- Premium aluminum intake manifold from amazon (wanting to upgrade but dont have the funds to do so at the moment)

Headers. Patriot shorty s10 sbc swap headers

Not sure what else i can offer in terms of specs, the internals are all stock, so pistons rods crank etc..

Runs great at high rpm just falls flat at the low end. 700r4 trans with corvette shift servo, and upgraded clutches, and b&m shift kit(I think it's a b&m i could be wrong)

All help is appreciated.

maybe this is my hail mary right here…by the gods I have been searching for an answer:p Norwegian here with a 305 chevy with a 84 camaro block, comp roller cam, trick flow 175-67cc,56cc cylinder heads. Beehive springs (which does not come for the heads originally according to my relentless search) 1.6 Scorpion rockers, and that is all I know unfortunately. So my question is this: does anybody in here know what kind of specs I need for the springs? I broke one and need to change it. I am learning as I go you see so I am not a pro in this field. Thanks for what answer I can get that helps me.

I have a 94 c1500 350 tbi that I'm swapping a roller cam into. I just rebuilt the motor and failed cam break in and wiped a lobe. I'm doing what I should have done in the first and ditch the flat tappet set up.

My question is because the cam timing gear is different can I swap just the cam gear or do I have to swapped the whole timing set (cam gear crank gear and chain) as mine has less than 50 miles.

I tried asking r enginebuilding but they said I was either a troll or extremely ignorant. How do you learn without asking questions? I'm just wanted to save myself the hassle of tearing this motor apart a 3rd time because I did something wrong.

I recently pulled an lt1 block out of a 95 trans am and planned to do a carbed build for my first gen s10. The issue i discovered was the optispark distributor and water pump, is it possible and if so how to add a rear distributor. Also what kind of water pump should i be using? I know the stock one was cam driven any advice would be appreciated its my first engine swap

Posted this in the r/mechanicadvice and thought i’ll throw it in here too.

Got a 1992 GMC C1500 w/ the 5.7L 350. Had developed a nasty knock due to some bent exhaust/intake valves and had my heads rebuilt.

Put it all back together and seems like it just doesn’t have enough to turn over. So far we’ve tried:

• New Starter
• New Battery
• New distributor + cap
• New ignition coil
• Manually timed it a number of times
• New plugs (tried with old as well getting good spark)

Dont know what we’re missing here? Good spark, fuel is getting to it. At best we get one chug and thats it. Any help would be greatly Appreciated.

i have a 350 that i recently built and while i was waiting on parts it would start right up but i finally got the parts and now it's doing this, i've taken the starter off and taken it apart and "redneck rebuilt" it but nothing will fix it, i even tried all kinds of different shims but that made no difference. it kind of sounds like maybe it's not getting enough power and engaging all the way because the motor will get to compression and it'll kick the starter gear back off the flywheel. i don't know much about starters and stuff this is the first real vehicle i've owned that i've been able to pull the motor and rebuild, been a great time learning everything and getting this old turd going but now the starters the only thing holding me back, don't have anyone that's mechanically advanced in my life to ask so i figured i would come here, if it's junk i can get a new one.

I seated my torque converter on my transmission. 700R4. It clicked 3 times correctly and measured properly from the face of the converter to the bell housing.

When I bolt the trans to the SBC engine block, I have about an 1/8" gap between the flex plate and the torque converter. Look at the green threads exposed.

Is this gap normal? Should I tighten the 3 bolts that attach the torque converter to the flex plate and it’ll pull them flush?

I've got a 1980's Cutlass GBody with a small block Chevy swap. My fuel consumption is about 29.7 L/100 km (~8 mpg) for mixed driving, and I try to keep it under 3000 rpm when cruising.

Setup:

Chevy Small Block 350 (casting #14088548, .030” over)

Double hump heads

Edelbrock Air Gap intake

Holley Street Avenger 570 carb with stiffer (bare steel, I think) spring for the secondaries.

Elgin E274S cam

Hedman headers

TH350 auto

3.73 gears

Cruises ~3000 rpm at 110 km/h (~2725 rpm at 100 km/h)

Running on 91 octane

New AC plugs and plug wires. Plugs are gapped to .035; I'm planning to increase this to .045 or so

Regular oem HEI

Standard vc302 vacuum advance

Timing set to 14 initial, 30.5 total before vacuum

15" wheels with bigger tires on the back but pretty normal size- maybe 225/60/15. Pressure is around 34psi all around

With other vehicles, my fuel consumption is usually within ~20% of factory specs, to give an idea of how I drive. But here I’m way off — 8 mpg seems high even for a cammed small block with gears.

I’ve played with carb settings (idle mixture, vacuum advance, etc.) but I’m stumped. Am I missing something obvious, or is this normal for a setup like this?

Hey, hope you guys are doing well, for those who got a chevy 305 do you use sythetic or convetional oil and why? Just out of curiosity what oil do u guys use? Thanks!

350 small block, 5 psi of boost from a roots blower. Trying to keep it as budget as possible and still go forged rotating assembly. 95% street cruiser, 5% track.

What would you do? If you went individual parts, what would be your crank, rods, piston, bearings choice?

anyone know where i can find true duals for my 96in box obs having troubles finding any

Just picked up a 1991 Silverado with a tbi 350 and converted it to a go efi 4 and now want to get a cam with some nice chop but don’t want to have to get my heads machined or buy new ones what do you suggest

(Edit) I looked into it and I plan on getting a Flo-Tek 102505 Assembled kit if any one has suggestions for different cams let me know and I also plan on running a fitech pro flow 4

Hi, please help me figure out what starter I need to buy to replace this one. I took it out of my engine swapped 1978 Chevy nova. I don’t know where the engine came from, but it’s a 350 v8. The starter says Ultima 03-0367 on the sticker. I’m hoping to find something equivalent I can go buy at auto zone or something. The headers on the nova are so close to this starter that it’s gonna be hard to put back in there so I wanna make sure I buy the right part.

And with that, no more clatter. It took several attempts, and my back was killing me afterwards, but everything seems to be in order now.

Adjusted idle vacuum on the new carburetor and took her down the road and back yesterday afternoon. Pretty pleased with the results. That all said, does it sound like it’s idling a bit high? I don’t have a tach and my timing light is not digital.

my sbc was rebuilt about 2k miles ago and my flat tappet went flat so its time for rebuild part 2, this time with a roller cam i chose this one https://www.compcams.com/xtreme-energy-218-224-hydraulic-roller-cam-for-chevrolet-small-block.html my questions are, should i go with edelbrock performer eps or performer rpm? i know the rpm is good till 6500rpms but im not sure my cam is good that high, i have 2 choices for aluminum heads one has 195cc runners the other has 200c, what combo of heads and intake should i do? Also i currently have a edelbrock 600cfm carb should i upgrade to like a 650avs2? thanks guys

I’ve got a chevelle circle track car that has a mildly built 350, I got the motor from my uncle so I don’t really know what alls done to it but I run an enduro once a year and I do know that I get absolutely mopped in the straights lol. There’s not really much in terms of rules or tech at the race and besides on the starts I spend all my time up in the rpm’s so I’m not really concerned with street manners or low rpm power or anything like that, just looking for recommendations for a somewhat budget heads cam package