Does anyone know where i can find information or specs on the stock camshaft for a 1986 4.3liter? I'd like to know what the stock duration and lift is so i can pick a replacement cam with a LITTLE higher lift. Thanks guys
Does anyone know where i can find information or specs on the stock camshaft for a 1986 4.3liter? I'd like to know what the stock duration and lift is so i can pick a replacement cam with a LITTLE higher lift. Thanks guys
im looking for the same stock info havent found it yet but i did find the crane cam web site very helpfull! good luck ( www.cranecams.com ) ps if you find the stock lift/dur please let me know Thanks cgvett@optonline.net
Specs to the stock cam? Try round lobes. Picking a replacement is easy.
My information says the 4.3 still used a flat tappet camshaft in 86.
I recommend the Isky 256 Supercam. It has the following specs:
Duration @.050 .202 Intake .202 Exhaust.
Lift @ Valve: .425 Intake .425 Exhaust.
Lobe Center: 112
RPM Range: 1500 - 4800
Application:
Best torque and economy in passenger cars and trucks.
Max compression ratio 9.5:1. Smooth idle, standard axle ratio,
Good vacuum. Computer Compatible.
Standard to 600 cfm Carb.
Cam Part Number: 121256.
This cam is the smallest of the line, and it may as well be considered a stock replacement cam. The stock cam is not a great deal smaller than this cam. This cam will aide low end torque development that you'll be able to feel in the seat of your pants. It will help driveability as well as fuel economy. Make sure you get the valve springs to match the cam and use a good double roller timing chain set. Are you using TBI or carb? If you would like other advice on helping the little six get better power and mileage just let me know as I've been playing with these engines since 2007. If your running TBI and would be interested in Venom Injectors, adjustable fuel pressure regulator as well as a Edelbrock performer TBI intake and a MSD blaster coil with less than 30,000 miles on it let me know, I got the whole package for sale cheap as I'm converting over to Vortec heads and carb.
I have a carbureted set up, came stock with rochester 4bbl, now i have an edelbrock 600 on it. I have been looking at Lunati voodoo cams, because they have some specially made for 4.3liter apps, which most other cam manufacturers focus on V8s
Also i just posted this question in the engine section but since we are on the subject of Chevy 4.3 liters.... My truck has a LB1 4.3liter carbed from the factory, and in the glove box info sticker it says Vortec 4.3 liter V6. I know Chevy didn't start marketing their heads under the Vortec name till like 96 but can you explain why Chevy called my engine "Vortec"?
The name Vortec came in the mid 1980's. Vortec is another name for Vortex which means tornado. The cylinder heads have a swirl vane in the valve bowls designed to swirl the mixture. These heads work great for low end torque development, but fall flat on there face at 4000 RPM.
If you already knew what cam you wanted to go with there wasn't much point in asking. Just about all the cam companies make 4.3 Cams, Comp, Isky, Lunati alone isn't the only company that put time and effort into 4.3 V6's. I hope you swapped a aftermarket intake on when you switched to the edel carb. other wise you have to use a adapter and the best place for a adapter is the trash. Adapters disrupt the mixture and the vacuum signal. I would have stuck with the Quadrajet, as it's one of the best street carbs made.
Well i had an idea of what i wanted, but i didn't want to go too steep, because i'm not tryin to build a race motor, just give mine a little more power. Sorry for the question but you did give me extra options which i thank you for. And i do have an adaptor, but looking at edelbrock intake to go with the carb pretty soon. It was a temporary fix because my qjet was going down hill and i needed my truck. So you say my truck has vortec heads?
Your truck has Vortec by name. The heads on your truck are swirl vane heads, the worst flowing heads in small block chevy and the 4.3 V6 in history. However the swirl vane heads is what gave it the name Vortec.
The desireable Vortec heads are completely different than the old school heads. The desireable Vortec heads didn't come along until 1996. They do not have a heat riser passage in the center of the manifold face. They have 8 mounting bolts that are straight up instead of 12 in a slant as the old school heads do. They have a heart shaped combustion chamber while the old school heads had bathtub shaped chambers. For the SBC, the casting numbers to look for are 062 and 906.
Casting numbers to look for on the 4.3 V6 Vortec heads are: 772, 140 and 113.
Specs to the stock cam? Try round lobes. Picking a replacement is easy.
My information says the 4.3 still used a flat tappet camshaft in 86.
I recommend the Isky 256 Supercam. It has the following specs:
Duration @.050 .202 Intake .202 Exhaust.
Lift @ Valve: .425 Intake .425 Exhaust.
Lobe Center: 112
RPM Range: 1500 - 4800
Application:
Best torque and economy in passenger cars and trucks.
Max compression ratio 9.5:1. Smooth idle, standard axle ratio,
Good vacuum. Computer Compatible.
Standard to 600 cfm Carb.
Cam Part Number: 121256.
This cam is the smallest of the line, and it may as well be considered a stock replacement cam. The stock cam is not a great deal smaller than this cam. This cam will aide low end torque development that you'll be able to feel in the seat of your pants. It will help driveability as well as fuel economy. Make sure you get the valve springs to match the cam and use a good double roller timing chain set. Are you using TBI or carb? If you would like other advice on helping the little six get better power and mileage just let me know as I've been playing with these engines since 2007. If your running TBI and would be interested in Venom Injectors, adjustable fuel pressure regulator as well as a Edelbrock performer TBI intake and a MSD blaster coil with less than 30,000 miles on it let me know, I got the whole package for sale cheap as I'm converting over to Vortec heads and carb.
WOW DV thanks that was really helpful i just bought this new 85 4.3l crate motor from pace performance (new gm leftover) for 500 bucks to replace the 3.8l in my fishing boat.I needed that info to be sure i wouldn't suck up water on the ex stroke.thanks again if you have any more input to help me make this a great marine motor i would love to hear your ideas ! thanks Chris (cgvett)
Your Welcome. I'm here to help if I can. What mods would you like to perform? Are you looking for more overall power, low end power, high end power? As on boats the prop pitch has alot of influence on both. Just tell me what you have in mind and I'll see if I can lead you in the right direction.
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