carbed 350 questions
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Joined: Jan 2009
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From: Lansing NC 28643
Car: 91 Firebird, 89 Bird, 86 Bird
Engine: None, 5.7, 5.0 L.O.
Transmission: None, T5, Thm 350
Axle/Gears: 3.23, 02' 3.43 rear disc, ???
carbed 350 questions
Ok... I hope I'm posting in an appropriate place...
So I'm in the finishing stages of my motor for swap into my Firebird...
but first some motor questions... I'm swapping the 3.1 (0-60 eventually) for a 1973 5.7 monte motor. It has edelbrock performer intake, double row timing chain, 5.0 H.O. heads, and flat top pistons. My qestions are what size cam should I get? Will a Quadrajet give it enough fuel? If not what carb should I go with? Will a turbo 350 from an 80's sunbird have the right tail shaft to bolt up to that torque bar to the rear end? any help would be nice... And if you need to know anything else about the car or motor just ask. Thanks
So I'm in the finishing stages of my motor for swap into my Firebird...
but first some motor questions... I'm swapping the 3.1 (0-60 eventually) for a 1973 5.7 monte motor. It has edelbrock performer intake, double row timing chain, 5.0 H.O. heads, and flat top pistons. My qestions are what size cam should I get? Will a Quadrajet give it enough fuel? If not what carb should I go with? Will a turbo 350 from an 80's sunbird have the right tail shaft to bolt up to that torque bar to the rear end? any help would be nice... And if you need to know anything else about the car or motor just ask. Thanks
Re: carbed 350 questions
A Qjet carb is a good carb if it is adjusted right. You can do a google search and find the way to adjust them right. As long as it is an older Qjet and not one with all of the electronics on it will flow up to 750 CFM. It only supplys what the engine needs or wants. Only a street driven car I wouldn't put anything bigger than a 275 adv duration cam in the engine. Bigger doesn't always mean better.
Thread Starter
Member
Joined: Jan 2009
Posts: 105
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From: Lansing NC 28643
Car: 91 Firebird, 89 Bird, 86 Bird
Engine: None, 5.7, 5.0 L.O.
Transmission: None, T5, Thm 350
Axle/Gears: 3.23, 02' 3.43 rear disc, ???
Re: carbed 350 questions
ok what lift should I go for?
Re: carbed 350 questions
I would say no more than a .470 to .480. The thing to remember is use lots of break in lube on the cam and the bottom of the lifters, then add an oil additive to the oil for the break in. Keep the engine between 2000 and 2500 for at least 20 to 25 minutes varying the rpm's between the 2000 to 2500. By doing this you are making sure the lifters will spin in the lifter bores to get them to seat right, this also splashes oil onto the cam and lifters to keep them lubed and cooled.
Thread Starter
Member
Joined: Jan 2009
Posts: 105
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From: Lansing NC 28643
Car: 91 Firebird, 89 Bird, 86 Bird
Engine: None, 5.7, 5.0 L.O.
Transmission: None, T5, Thm 350
Axle/Gears: 3.23, 02' 3.43 rear disc, ???
Re: carbed 350 questions
not trying to seem like a complete idiot but I have no idea what kind of cam your supposed to use for this kind of set up lol there are a few I know but...
Retro-Fit Hydraulic Roller ?
Hydraulic Flat Tappet ?
Solid/Mechanical Flat Tappet ?
Solid/Mechanical Roller ?
Retro-Fit Hydraulic Roller ?
Hydraulic Flat Tappet ?
Solid/Mechanical Flat Tappet ?
Solid/Mechanical Roller ?
Re: carbed 350 questions
No big deal man. Not everyone knows everything that is why you ask questions.
From 1955 to 1986/1987 GM used either a solid or hydraulic flat tappet in their engines. After that GM moved up to roller cams in thier engine. So you will either need a Retro_fit hydraulic roller or a flat tappet cam. The lifter bores on all of the engines are the size but the newer blocks have taller lifter bores. You can take a roller cam engine and run a flat tappet in it with no problems, but to run a roller in a older engine you have to have lifters with a connecting bar, special lenth push rods and that kind of thing. You can go to a roller in the engine but you will be looking at about $1000 to do it. If you go that way it is best to buy a kit where everything is matched and it is not so confusing that way.
From 1955 to 1986/1987 GM used either a solid or hydraulic flat tappet in their engines. After that GM moved up to roller cams in thier engine. So you will either need a Retro_fit hydraulic roller or a flat tappet cam. The lifter bores on all of the engines are the size but the newer blocks have taller lifter bores. You can take a roller cam engine and run a flat tappet in it with no problems, but to run a roller in a older engine you have to have lifters with a connecting bar, special lenth push rods and that kind of thing. You can go to a roller in the engine but you will be looking at about $1000 to do it. If you go that way it is best to buy a kit where everything is matched and it is not so confusing that way. Joined: Dec 2005
Posts: 6,499
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From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
Re: carbed 350 questions
not trying to seem like a complete idiot but I have no idea what kind of cam your supposed to use for this kind of set up lol there are a few I know but...
Retro-Fit Hydraulic Roller ?
Hydraulic Flat Tappet ?
Solid/Mechanical Flat Tappet ?
Solid/Mechanical Roller ?
Retro-Fit Hydraulic Roller ?
Hydraulic Flat Tappet ?
Solid/Mechanical Flat Tappet ?
Solid/Mechanical Roller ?
Solid lifters are lighter (tehy're not filled with oil) and they're generally for motors taht see very high RPMs as tehy're lighter and just generally work better for that sort of work. They require maintenance though. You'll need to reset valve lash at regular intervals (adjusting the rocker arm height on the stud) whereas hydraulic lifters basically adjust themselves unless there's a problem. Most factory cars and I'd say most hot rods even have hydraulic lifters. They're just a bit more user-friendly, require less maintenance, and work fine for most people.
Now you have to consider roller vs flat tappet. A roller lifter can be hydraulic or solid, and a flat tappet lifter can be either hydraulic or solid. Doesn't matter. A roller lifter can use much more aggressive camshafts and make a lot more power. They are also not as prone to failure. This is what ahs been used since 1988 in most factory sbc's (There are exceptions). They use a roller to ride the cam in the same way your wheels on your car ride on the road.
A flat tappet lifter works a lot differently and the whole lifter must rotate along the axis of the pushrod to stay lubricated and ride the cam lobe as it goes up and down. Modern oils aren't formulated for these types of lifters anymore since they dont make flat tappet lifters in new cars anymore. You'll have to take very special care to make sure a flat tappet cam doesn't grind down a lobe and put metal shavings all through your new motor with special lubes and additives. After break in this is much less critical, but for initial startup it's a very, very big deal.
Roller lifters are for the most part always better, but they cost more money. Flat tappet style cams are fine for most people, just take care in the early stages and you should be fine. Whether or not you go hydrualic or solid depends on what kind of power range you're tryign to hit and how fast you want/need to spin the motor. IF you're gonna keep it under 6,000 RPMs and you dont know the difference between teh cam types yet, I'd say hydraulic is probably the better choice for you. Solid lifters require regular maintenance and tend to only be used in fairly serious builds that are meant to rev a bit higher than most.
If your block can take roller lifters you should use them. If it doesn't take roller lifters, the retrofit rollers will usually work, but they cost a lot more money than regular roller lifters. If your block is a 1973 block, it cant take roller lifters. Your best bet is to go flat tappet unless you've got the money to burn on nicer roller setups.
Last edited by InfernalVortex; Jul 13, 2009 at 03:35 PM.
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Thread Starter
Member
Joined: Jan 2009
Posts: 105
Likes: 0
From: Lansing NC 28643
Car: 91 Firebird, 89 Bird, 86 Bird
Engine: None, 5.7, 5.0 L.O.
Transmission: None, T5, Thm 350
Axle/Gears: 3.23, 02' 3.43 rear disc, ???
Re: carbed 350 questions
Thanks 
Ok so its lookin like its gonna be hydraulic flat tappet.
This entire build was a combination of me wanting to do it and a bet that I couldnt do it under 3000$ I'm at 20$ right now. I'm lucky people still barter
oh yeah the car will be driven mainly on the street with probably a weekend or two a month at the strip

Ok so its lookin like its gonna be hydraulic flat tappet.
This entire build was a combination of me wanting to do it and a bet that I couldnt do it under 3000$ I'm at 20$ right now. I'm lucky people still barter
oh yeah the car will be driven mainly on the street with probably a weekend or two a month at the strip
Last edited by Blk91Firebird; Jul 13, 2009 at 06:46 PM.
Thread Starter
Member
Joined: Jan 2009
Posts: 105
Likes: 0
From: Lansing NC 28643
Car: 91 Firebird, 89 Bird, 86 Bird
Engine: None, 5.7, 5.0 L.O.
Transmission: None, T5, Thm 350
Axle/Gears: 3.23, 02' 3.43 rear disc, ???
Re: carbed 350 questions
And all those plans worked out great and it was decently quick all up until the point that... I busted the block
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From: Waterford, MI
Car: 1998 Camaro Z28
Engine: 6.0L
Transmission: 4L60E
Axle/Gears: 3.73
Re: carbed 350 questions
What happened to it? Depending, it may be easy/cheap to repair at a machine shop.
Thread Starter
Member
Joined: Jan 2009
Posts: 105
Likes: 0
From: Lansing NC 28643
Car: 91 Firebird, 89 Bird, 86 Bird
Engine: None, 5.7, 5.0 L.O.
Transmission: None, T5, Thm 350
Axle/Gears: 3.23, 02' 3.43 rear disc, ???
Re: carbed 350 questions
Stupidity and impatience 
It could be fixed and I would love to fix it but I traded the motor, minus the heads and intake, for a 79 K20 put the motor from it into my bird and it was knocking like hell (didnt notice it before I pulled it) now I'm rocking a 89 305. definitely moving up

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