exhaust options for 85camy

[rockhard]

I really need to get a new exhaust for my car because the current one thats on my car is horrible.
when the car is idling in one spot I can hear exhaust exiting from right below the 2 front doors and it is noisy as hell. on rare occasions I can smell exhaust in the car too.
so instead of getting a stock replacement exhast I want to spend a few extra bucks and get more of a performance system.

what type of options might I be available for my 85 camry?
any input thanks

[Tommy]

custom. just go to a muffler shop and have them put new pipes and a muffler on.

[te51levin]

I would not expect any performance gains from that. The entire 2S-E and all its systems are designed for quietness and durability, NOT for performance, and I really doubt that the existing exhaust is what's keeping the car from making horsepower. However, there is a tiny snorkle on the airbox that you can cut off and replace with a larger piece of flexible tubing if you like. Advancing the timing 5 degrees ahead of stock also helped pick up some bottom-end response on our old '85.

[rockhard]

what is the best type and size of metal tubing I could use to custom weld my own exhaust
2inch, 3inch?, stainless steel, aluminized ?
3 inch would probably be better right because an increased diameter means higher flow rate right

[te51levin]

Use exhaust tubing in approximately the same size as stock. There's no need to reinvent the wheel here. I really think any effort made towards building a "performance" exhaust is going to be wasted on a 2S-E. It will not make a tangible difference.

[Tommy]

Originally Posted by te51levin

Use exhaust tubing in approximately the same size as stock. There's no need to reinvent the wheel here. I really think any effort made towards building a "performance" exhaust is going to be wasted on a 2S-E. It will not make a tangible difference.

werd

Putting a 3" exhaust will actually reduce power. engine's rely on backpressure to a degree, to create the maximum hp, with no modifications to the rest of the engine, anything bigger than stock will do more harm than good.

[rockhard]

and my engine soon will not be stock ask if ya wanna know.... and well im not really trying to get a high performance exhaust anymore, i just wanna build up a semi perf.. system,
i would like to know what size would work best.. and if its the stock size then I would use that but i wanna go bigger maybe .25" or .5" more. whatcha think

[Tommy]

depends on what you are doing - stay N/A and you want 2.25" max, if you go turbo, then 2.5"-3" max

curiousity though - what exacty CAN you do to a 2SE?

[rockhard]

Well its no turbo or anything and you may think im crazy but I am porting and polishing the intake and exhaust manifolds, cyl heads, Combustion chamber polishing, and gettin a valve job..
I am custom directing my air intake and getting upgraded fuel injectors..
thats just bout it but exhaust comes first

[Tommy]

if you upgrade the injectors, youll need an upgraded ignition system, MSD+a new coil, go for the 2.25" exhaust, and even then, with all the head work youll be lucky to get 15-20hp

[rockhard]

oh well I think its worth it.. because Im gonna be doing the intake, exhaust, combustion chamber and most of the cyl head port and polish myself... but the valve work done at a machinist
then for the exhaust I will probably go for the 2.25" stainless steel tubing

[te51levin]

Originally Posted by Tommy

if you upgrade the injectors, youll need an upgraded ignition system, MSD+a new coil, go for the 2.25" exhaust, and even then, with all the head work youll be lucky to get 15-20hp

I don't want to pick a fight, but this is 100% incorrect. There is absolutely no reason that larger injectors would tax the ignition system, coil, etc. The headwork is the only thing in this equation that might make power, and even then, 15bhp is probably far more than you will ever see out of this project.

"Porting and polishing" manifolds is next to useless. You *might* find some very slight rough spots to clean up, but I doubt you'll find anything that actually nets you any gains in airflow.

Porting the head, if you do, should be done by a pro. Hogging the port out at the face, as most people do when they perform a "port and polish", typically does nothing but burn up time. In reality they are neither porting nor polishing anything.

"Upgraded" fuel injectors (assuming you mean "larger") are also not going to do you any good. The fact is that without significantly more airflow into and out of the engine, there is no need for additional fuel. Toyota usually leaves a good margin of safety when they choose a fuel injector, and your current injectors probably have more than enough capacity to support more airflow if your modifications actually create that airflow.

The 2S-E is a SOHC, 8-valve, non-crossflow, low-performance passenger car engine. It was not designed to make a lot of power, and no amount of bolt-on gimmickry is going to change that. Rather than try to reinvent the wheel, why don't you find an '86-'89 Celica GT-S with a 3S-GE, and swap that into your car? Then you'll have an engine that was designed from the start to spin decent RPM and move some air. You'll also be able to take advantage of more performance mods by sharing some of the goodies available to the MR2 Turbo community.

Please, READ and LISTEN before you decide to spend money on that engine, or that car. DO NOT call up vendors or visit shops and ask what you can buy for your engine, because they will probably try to sell you anything they have. And since there's nothing short of a full teardown and overhaul from stem to stern that is going to make that engine powerful, you are going to be giving your money away and getting nothing in return.

[Tommy]

its not that hard to modify the AFM to get it to allow for more air, and physics proves that an increase in air+fuel+spark, youll get more power. It wont be a lot, but i specifically said it wasnt going to amount to much.

but i do agree with what you said, and modifing the 2SE is about as pointless as it gets. Gen1 is an ugly car with a crappy engine, much better off taking the $1000 youll spend and buy a better starting point.

[te51levin]

Originally Posted by Tommy

its not that hard to modify the AFM to get it to allow for more air, and physics proves that an increase in air+fuel+spark, youll get more power. It wont be a lot, but i specifically said it wasnt going to amount to much.

but i do agree with what you said, and modifing the 2SE is about as pointless as it gets. Gen1 is an ugly car with a crappy engine, much better off taking the $1000 youll spend and buy a better starting point.

The AFM is not the limiting factor in airflow. Modifying it will not allow more air into the engine because the engine isn't capable of moving more air.

More air + more fuel = more power, but without a complete, ground-up, full-tilt attack on the breathing characteristics of this engine - and that means redesigning the intake manifold, extensively modifying the cylinder head, replacing the entire exhaust system, and changing the camshaft - it's not going to pump much more air. Plain and simple, that is why there won't be much more power.

The "increase in spark" thing is a bit of a myth. A stronger spark will make ZERO difference if you already have enough spark to light the mixture consistently, and that is what a stock coil does. A blowtorch doesn't light a firecracker any better than a kitchen match...all you really have to do is light the fuse. The stock coil lights the fuse. Fancy coils are not required on anything approaching stock, because Toyota supplies coils that get the job done.

I also missed an opportunity to address the myth that engines need backpressure. That is a very old, very popular lie, but it's a lie nonetheless. What street engines need is a manifold/header size and design that produces best power over a broad range of engine speeds. What that means is that it is a compromise between velocity at lower speeds and backpressure at higher speeds. The velocity that small-tube headers provide is good for torque at low to moderate speeds. An unfortunate side effect is that those systems induce backpressure at higher speeds. Backpressure is NOT your friend. It is a necessary high-RPM evil of a reasonably sized and designed header/manifold that works well at low to mid RPM. Repeat after me: Engines do not need backpressure!

I think the absolute best thing that could come out of this project is that the OP will not get ripped off too badly. At best, he'll get a decent exhaust system that fits well and last a long time, and maybe some machine work that will help the engine stay together for another eight or ten years. It will all probably be sold to him as "high performance", and the results will probably be no better than stock. But then, many parts and services sold as "high performance" should really be called "not as crappy as our usual low-grade junk".

If you really want a project for the sake of experimentation, go ahead. If you want power, start with an engine that was designed to do what you want to do.

[Tommy]

you contradict a lot of common knowledge, you think its a myth, although many of these things have been proven by dyno runs. not necessarily on camry's or even toyotas, but proven none the less.

for fun a few years back, me and a friend did all of these things to a 88 CRX, was a POS slow ass CRX beater that he had sitting in his back yard. Increased fuel injector size, msd, blaster coil, advanced the timing...ect.... we didnt do any of the head work mentioned, but the car did have 4-2-1 header and a 2.5" ricer fart can exhaust.

While this certianly didnt turn the car into a beast, there was a noticeable difference.

This goes along the same lines of replacing the jets in a carb. you spray more fuel in, as long as there is enough spark, youve got more power. Replacing the jets on my dad's motorcycle and throwing on some high flow pipes yielded 10hp.

back pressure is a bit of a misnomer though, really what you are trying to do with properly sized pipes is keep the exhaust velocity at an optimum speed. The back pressure refers to the lower pressure zone created by the valves opening and closing near the manifold, if the size is too big, exhaust exits slower because there is not enough volume to fill the pipe, If the pipe is too small, then the flow will cool faster and cooler gas = slower moving.