What can I do to increase horsepower in my stock 350 engine without having to pull my engine?

Question

I have a 71 Impala with a 350 motor, 2 barrel Rochester carb, stock everything. I want to beef up the engine and make this thing go. What can I do?

Answer 1

there is so much you can do to this car, and it comes down to how much you want to spend and how fast do you want to go?

so lets start with the easiest first.
headers up to 15hp 10lbs tq
high flow mufflers and pipes 8 to 15hp & 6 to 12lbs tq
H-pipes for low end torq 5hp & 21 lbs tq
after market pullys up to 21hp & 15lbs tq
after market fuel pump 3 to 5hp
HEI distributor as much as 30hp over points distributors
ignition box as in MSD as much as 50hp
and if you dont want to change your intake holley makes a 500cfm 2 barrel carb you'll get as much as 35hp & 40lbs tq
and theres the trans a shift kit will help big time in over all performance

now here alittle more work but you can do it your self
roller rockers 15hp
4 barrel intake and carb as much as 60hp
cam but remember to keep the lift at or under 500
with roller timing chane as much as 100hp

and all this can be done in your drive way, but there so much more you can do from there as well.

check it all out at summitracing.com or call em at 1-800-230-3030

e-mail me for more info

Answer 2

This is a heavy car so while you are on the right track by wanting to increase horsepower you should consider a gear ratio change best bang for the buck at best that heavy Chevy is pulling 2.73 in the third member how about a very street-able 3.50 set,also keep it simple on a stock motor you are going to have to keep the cfm's on the carb to under 600, but they make plenty of carbs at 580 to 600 cfm's,also headers and duals that are flowing to a good quality turbo or open chamber muffler,after all when you are talking about acceleration you are not really talking about horsepower you are talking about torque and yes an H pipe does work,also when you buy an intake make sure it is a dual plane intake these offer more low end torque,you will have to upgrade to HEI and 8 or 8.8 mm plug wires as a minimum,if you try these you will notice a good increase in torque and drivability.

Answer 3

a four barrel intake and carb is step one. You can upgrade the plugs and wires as well. If you do not have an electronic distributor that would be next. You can remove the heads without pulling the engine and upgrade the valve job You can also add performance exhaust headers (big HP gain) without pulling the motor.

One thing to think about is all of this will be for nothing if the engine is excessively worn. If it has never been rebuilt, 37 years is an old engine. And although it may seem daunting, if you have the skills to do the above mentioned tasks, pulling ad rebuilding an engine is not as complicated as it seems, especially on an old Chevy....

Answer 4

There are lots of things. A four barrel and manifold will deliver more fuel and air into your engine and exhaust headers and thru flow exhaust will help you move if through faster.

Both will add a large amount of power. Just make sure you do not restrict the flow of air into that bigger carb. You need a lot of air to convert fuel into power.

A hotter spark delivery system such as an ACCELL high performance system will help, too. All of this power may be too much for you transmission and rear end. That too many have to be modified to handle the extra power. Otherwise, you will have difficulty getting the extra horsepower to the ground.

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Answer 5

Buick 350 Headers

Answer 6

Headers improve flow and increase HP as does a larger carb and intake manifold. If you don't want to take off anything hard, try getting a new high flow air filter. That alone will boost you 5-10 HP. Then replace the muffler with a better one with less restrictions and that will boost you another 5-10 HP.

Answer 7

How To Improve Horsepower

Answer 8

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Answer 9

Buy a Holly or Edelbrock 4 Barrell carbuerator, and an exhaust system. You will notice power increase right there.

Answer 10

could get a blower?......or change the cam and the heads intake and carb get an msd box along with a new distributor...underdrive pully set all can be done without pulling the motor but an old cast block can only take so much with stock crank,pistons and rings