My 1987 22r toyota pickup needs some spice, and i was wondering if i could bang out the cat without any further modifications? Would it do anything bad?

 

Why do you want to do that?

What do you mean by "spice"?

Do you like to breathe? I know I do. As the name implies, a catalytic converter converts toxic gases that are emitted from your engine and converts them into less harmful gasses.

If your catalytic converter is working properly (i.e. the catalyst is not clogged or damaged), you should not gain anything from smashing out the catalyst other than breathing in more toxins.

 

 

In that case, do you recommend an exhaust system to deepen its tone or make it not so quiet? I'm happy with with its performance, and don't want to hurt the engines longevity. But just looking for suggestions.

 

i wanted to do it because its already rusting out and starting to have leaks, it needs to be replaced regardless.

 

 

O.P., Please stay away from where I live, drive and play.

Like I said in other thread, save money and buy a header.

 

I should have given you my rusted out exhaust and muffler before I replaced it!

The truck was quite loud (kind of a raspy fart-can exhaust sound). The truck sounded cool for all of five minutes. Then it got annoying.

A new muffler and exhaust would more likely give you the results you are looking for.

 

I'm pretty happy with my exhaust, Thorley header, hi-flow cat (mine was dead,) cat back exhaust and pro-flow muffler. Not overly loud, not ricey, just a nice rumble down low. Gets a little annoying when you rev it out, but after all it is a 4 banger.

 

Cats are needed for emissions tests. If you dont need to do such a test there is no need. The vehicle wont smell any different if your air fuel ratio is normal. This isnt a diesel. The stock oem exhaust is very weak. It should be 2.5" minimum. 3" cant hurt and theres plenty space for it. Cats, resonators.... Dont do much for sound. Mufflers take care of noise, a quality chambered muffler of adequate size will be quiet as stock. Do it all in stainless, and it will last.

 

Where are you getting this information from?

My factory exhaust seemed pretty strong to me.... high quality for aluminized steel...

Bigger is not necessarily better.

There is a LOT of engineering that goes behind designing a proper exhaust system. You cannot simply slap a large diameter exhaust on and magically gain horsepower. You may actually lose performance if you are not careful. The exhaust system should be designed around the engine and the best balance of flow, scavenging, and exhaust velocity for the intended RPM range that the engine will be operating in the most. These factors will vary depending on if the engine is stock or modified.

 

 

You're flat out wrong. Bigger is not always better when it comes to exhausts. If you're talking a turbo or diesel application then you want as free flowing as you can possibly get. On these 22r motors anything over 2.5" is going to rob you of some low end power.

 

 

Seriously a 3" exhaust on a 22r motor? 2.5" is the very biggest I have seen recommended. Most people find a happy place with 2" or 2.5". 3" would probably eliminate most of your bottom end power.

@the171. Please if you are going to give contradicting information to most everybody's experience with the 22r series motors could you please at least tell us your real experience with these motors? I will start, I have had a 85 22re pickup, 89 22re pickup, 93 22re pickup and now a 85 22re 4runner. My experience with this motor is still limited mainly because I have on fully rebuilt 1 and done head gaskets and timing chains on the others. Nor have I ever seen a dino sheet for one I have owned. However I have played with many different intakes and exhausts in the process and in all cases if your going to do something like a 3" or straight header you need to allow the motor to use it or you are just throwing money at something for giggles.

Most all of the 22re guru's LCE & ENGNBLDR both recommend 2.25" for best power and drivability.

 

Please show us a dino sheet where a stock ish 22r or 22re motor makes more power with a 3" vs 2.5". Turbos and diesels don't like back pressure. However back pressure doesn't always hurt you. Many exhaust systems utilize scavenging, one example is the already spent exhaust in the pipe helps pull the newly created exhaust out. Its more commonly used with 2 strokes but the same applies to most all motors. These motors produce most all the "power" in the head. So to put a big exhaust on without making sure the intake and engine can handle the ability to get more out without getting more in and through is money wasted. I have run stock, 2", 2.25" and 2.5". 2.25 i felt gave me the best drivability.

 

 

Well that discussion degenerated quickly. Perhaps because it included those who announce their unsupported opinion, and when asked about it, insist "certainly I am not wrong." Why am I not wrong and others are? Because "im into exhaust and welding."

It may just be me, but if I was the one "into" a subject, I would be able to do the necessary calculations in my sleep (and could repeat them when called for). Short of that, I could cite to a half-dozen of the more respected publications. (A quick google search turned up
https://www.hotrod.com/articles/what...pes-work-best/
http://www.exhaustvideos.com/faq/how...pipe-diameter/
https://blog.tdotperformance.ca/guid...pipe-diameter/
I can't say that any of these are authoritative, but they do seem to back up their claims with calculations. Oh, and none of them buy into "bigger is always better.")

Or, I could just claim that "most who know what's up" agree with me. But that would NOT be advancing the discussion.

So let's try to keep it informative. I want to hear your opinion, but back it up!

 

YUP.
Opinions without verification don't matter.
DYNO before and after will the fact.
I wonder how much shop would charge for this?
Anyone who's planning to mod the exhaust willing to do this?
​

 

There are formulas and books (plural) on engine tuning including exhaust system length and diameter. A friend of mine has/had the formulas on his computer (DOS) and we did the measurements and ran the numbers. When we ran the numbers for a big pipe on different small 4 cylinder engines the useful RPM range decreased as compared to the smaller pipes.

2 of the books are:

Scientific Design of Exhaust and Intake Systems (Engineering and Performance)

Performance Tuning in Theory and Practice, Four Strokes