Its a 1975 chevy 350 & the mechanic said "Those headers always leack exhaust". But I'd rather use them than not. so how much power would it gain. I've read that the engines only 165 HP stock but I think it was rebuilt so I'm unsure if its stock inside or not. Its extremely clean with no leaks visible.
2007-02-16 19:22:06 · 7 answers · asked by Willis C 3 in Cars & Transportation ➔ Car Makes ➔ Chevrolet
Stock exhaust 2 1/2 inch with no cats. maybee duals in future with edelbrock 600 carb.
2007-02-16 19:30:05 · update #1
You could unlock so much horsepower from that motor if you took off the smog pump and changed to 3" dual exhuast and a 4 barrel carb. My friend has a 77 Nova 350 and he went from a sad 165hp to around 300hp just from changing those parts.
2007-02-16 21:22:43 · answer #1 · answered by the Animal 3 · 0⤊ 2⤋
I own a shop, and have built many engines over the years. A good set of headers is worth about 20-25 horses. Since torque is what moves the vehicle, it is important to look at this as much as you do horsepower. Headers won't do a thing if you don't open the exhaust up so it breathes, as in 2 1/2 - 3 " pipe all the way out, with good flowing mufflers such as glass packs or flowmasters. The long tube headers will give you more torque than the shorty's, and don't go over 1 5/8" into a 3" collector as bigger is not always better on a small block. Giving the engine a few more degrees timing will do a lot for the engine too. Using a big free flowing air cleaner will help it a lot. You want to give it all the timing you can, and the engine will still start OK without dragging the starter or spark knocking. More timing may need higher octane fuel, but the difference may be worth it. Tighten the header bolts every two weeks, and they won't leak on you, but if you don't use quality headers, they can be a problem keeping them from leaking.
Glad to help out, Good Luck!!!
2007-02-17 00:47:22 · answer #2 · answered by Anonymous · 0⤊ 0⤋
sixty 5 chevy HD with a 350, if that is unique engine nicely maintained 8-ish seventy two Z with a 305, same circumstances 15-ish The truck is in all probability around 3 a lot, and the automobile around a million.5, plus the aerodynamic properties are way diverse between the two, yet you're nevertheless speaking carburetors, or maybe the slightest mis-adjustment would reason significant variations to MPG. there is likewise approximately 10 million variables that make this stressful to wager at. The Z ought to have had a super cam put in it (greater ability, much less MPG), had ignition enhancements (greater valuable MPG and greater ability), and endless different issues. the two inventory and exact tuned nevertheless, two times the MPG for the Z is a reasonably sturdy wager "off the cuff".
2016-11-23 14:34:46 · answer #3 · answered by ? 4 · 0⤊ 0⤋
No here has mentioned adding a high voltage ignition coil. Perhaps one of the cheapest bolt on horsepower you can ever do. Other than a good carb then headers. Since its a 1975 adding the racing coil can improve performance. fuel efficiency as well as having the engine breath better due to leaner and cleaner burns.
2007-02-17 10:01:30 · answer #4 · answered by Kill_Me_Now! 5 · 0⤊ 1⤋
Headers will probably add 10-15 horsepower to your engine. A lot also depends on what exhaust system you choose too.
2007-02-16 19:28:10 · answer #5 · answered by m k 5 · 0⤊ 1⤋
headers will give you more horses put the style of hedder will make a differance. You need to find out what cam is in the motor?
There are many things that can make a difference when it comes to motor specs.
2007-02-16 23:01:21 · answer #6 · answered by kissmywinnie 2 · 0⤊ 1⤋
you might get extra 20 hp
2007-02-16 19:27:03 · answer #7 · answered by gregs111 6 · 0⤊ 1⤋