Hi, the exhaust manifold on my 1997 corolla has a huge crack in it. Was thinking of either replacing it or getting headers. my car is all stock. can any one give me some advice on the pros and cons for headers? is there any one who has headers and how does it preform? Could headers do damage to the engine?
Headers? Stay with OE Exhaust Manifold?
- Thread starter cokumura
- Start date
Headers are noisier. You have to be careful in the way the rest of the exhaust is going to fit; so without stress to the headers (crack!!). The first weeks you have to check regularly the way in which the headers are fitted to the cilinderhead. They tend to get loose; nuts should be used in combination with Loctite, and even then you have to check it regularly. Headers do not cause damage to your engine. You only get optimum extra HP in combination with a tuned exhaust system.
They are fine for high RPM power/racing, but can reduce bottom end torque, which reduces fuel economy. If you're going racing, with a Corolla, fine. But if you're just driving around, you'll save your money in better fuel economy using the stock exhaust manifold. To replace the stock exhaust manifold, I'm sure you can find thousands of them in junkyards all across the country at the below website. Good luck with it -
http://www.Car-Part.com
http://www.Car-Part.com
Get the stock manifold!
Headers on a 93.....no man, you"ll have no back pressure just for normal driving, they only work if youre going to put it to the floor at every single green light, if you want to make your corolla badass where its already good go with
k&n high flow air filter
AMSOil full synthetic 10w30
purilator or fram premium oil filter
thermo quiet ceramic pads and shoes from wagner
any good fresh rotors
race quality wheel bearings
pirelli p4's (usually $70 from discount tire)
after these upgrades your efficiency makes the prius even more of a joke but you also get as much bhp as you can get from stock specs without compromising the integrety of the engine
and seal it all up really well with high temp silicone (red)
Headers on a 93.....no man, you"ll have no back pressure just for normal driving, they only work if youre going to put it to the floor at every single green light, if you want to make your corolla badass where its already good go with
k&n high flow air filter
AMSOil full synthetic 10w30
purilator or fram premium oil filter
thermo quiet ceramic pads and shoes from wagner
any good fresh rotors
race quality wheel bearings
pirelli p4's (usually $70 from discount tire)
after these upgrades your efficiency makes the prius even more of a joke but you also get as much bhp as you can get from stock specs without compromising the integrety of the engine
and seal it all up really well with high temp silicone (red)
Last edited by a moderator:
My Corolla had the same cracked manifold issues (between cyl 2 n 3). I replaced with stock manifold. What i did notice on the install was the support brace from the block to the manifold. The hole didnt line up. To make it line up I would have loosened manifold nuts to get the brace-to-manifold hole to line up. Then re-tighten manifold nuts. Bad Deal!! That would create stresses on the exhaust causing THE SAME CRACK TO RETURN! Thats likely why the manifold cracked in the first place (before i owned it). I opened the hole on the brace til the bolt started then put a bigger washer on the brace-to-manifold mounting bolt. Maybe the casting was off or the poor Chinese machinist wasnt allowed to eat that day. Just a little heads up.
Totally depends on the design of the header. Backpressure is kind of a mis-nomer... People think that because smaller exhaust systems create more low end torque it is because the smaller system creates more pressure in the exhaust system, this is totally completely NOT TRUE. What it does, is harness the momentum of the moving air to create a vacuum in the exhaust system as the valves close, helping to pull more air / fuel into the cylinder. This is why it is SO critical on 2 stroke engines... The exhaust and intake are open at the same time usually so if you don't have the momentum of the exhaust gas to empty the cylinder, what is going to pull more air in?
The exact same principle works on an intake, only in reverse. Using the momentum of the moving air to pull or push more fuel / air into the cylinder. So the real question is... Is the stock exhaust manifold really tuned for low end performance? Does it actually help low end torque? Does anyone have dyno numbers? For the exhaust manifold you are taking off vs.. the header you want to put on?
I'd go for it! I suspect you won't notice much difference on low end torque. I don't think it will effect your fuel mileage much either... but... idk...
Alright, now bring on the nay-sayers!!
The exact same principle works on an intake, only in reverse. Using the momentum of the moving air to pull or push more fuel / air into the cylinder. So the real question is... Is the stock exhaust manifold really tuned for low end performance? Does it actually help low end torque? Does anyone have dyno numbers? For the exhaust manifold you are taking off vs.. the header you want to put on?
I'd go for it! I suspect you won't notice much difference on low end torque. I don't think it will effect your fuel mileage much either... but... idk...
Alright, now bring on the nay-sayers!!