BJ73 3B exhaust options

[Tennessee Jed]

Looking at probably needing to replace the exhaust on my new truck in the next year. Bone stock 1988 3B, not going to turbo. What is best in life? Stainless? What is the optimal diameter? Should I just go to an exhaust shop and have them replicate what is there now?

Thanks

 

[John Galt]

Do not duplicate the landcruiser muffler. Replace it with a straight=thru glass-pack type. I'm using a Flow Tech from Amazon
https://www.amazon.com/FLOW-TECH-50250-Glass-Muffler/dp/B00519330O?tag=ihco-20

 

[Dprio34]

John, are you running your glass pack under the right side door, or are you replacing the stock muffler with the glass pack leaving the stock exhaust system in place? How is the noise level with just the glass pack?

Also, not trying to high-jack this post, but I see a lot folks recommending 3" exhaust on this forum for Toyota inline Diesel engines. I am not expert in higher math, but I've read a few articles on exhaust systems in gasser V8s and unless you are pushing over 300hp, a 2 1/4" to 2 1/2" exhaust is all that is recommended due to engine scavenging. Anything above that, you loose torque due to loss of scavenging effect.

I am curious if anyone out there has any strong opinions on exhaust pipe sizing for inline 4 and inline 6 turbo charged Toyota diesels.

 

[John Galt]

I replaced the stock muffler with the glass pack leaving the stock exhaust system in place.

The noise level didn't increase much at all, it's not at all objectionable, and actually sounds a lot better IMHO.

 

[Tennessee Jed]

So should I stick to stock exhaust diameter? Or increase it? Only interested in the best stock performance over the long haul - no turbo.

 

[OGBeno]

Stock size will be fine for your needs.

 

[Dprio34]

I've seen a lot of people recommend 3" on here, but haven't seen any numbers to back that size up. 3" May be suitable for a Powerstroke or Duramax or Cummms in a Full size pickup, but I doubt we would realize any gains and it would probably interfere with something underneath the chassis. I am going to stick with stock size pipe unless someone can talk me out of it.

 

[Tennessee Jed]

Thanks Onur and Dprio - my thoughts exactly.