best headers and exhaust combination

[EcHo]

i remember back in the day someone actually took a lot of brands and had them dynoed and found the best combination for headers and exhaust for extra power. does anyone remember these?

[Jetes03tundra]

this might be somewhat helpful.....im looking at the XS power headers which are the former ss autochromes i just cant see the justification in spending 200 dollars more for jba's to just have the jba name.

SS Autchrome Headers - update?

[SNYDS]

check this link http://products.jbaheaders.com/asset...undra_dyno.jpg

[Azgoldrat]

JBA Headers, Stock Y pipe and replace stock muffler with a 18" Magnaflow.

[brusk]

Originally Posted by Azgoldrat

JBA Headers, Stock Y pipe and replace stock muffler with a 18" Magnaflow.

I don't know if they changed over the years but my 00 is the worst Y pipe of ANY car I've ever seen. Crushing them together is the stupidest thing I've ever seen. I bought the XS just because I couldn't stand the fact toyota put exhaust together so crappy. Then I realized my manifold was leaking so I felt really happy about buying them. To bad they don't replace the cat pipes. I havn't done it yet so don't ask for how I like them.

[Burger Steak & Eggs]

The newer ones have that also. Hard to believe they can make ~280 hp through that bottleneck.

[Azgoldrat]

Crushing them together is the stupidest thing I've ever seen.

That crushing actually cause's the exhaust pulse to move faster and is quite effective.Venturi effect. Replacing the stock Y-pipe showed lower torque numbers and little to No HP gains....Ever see a Gas powered RV Exhaust?? Big 454 engine...Tiny exhaust pipes....Its all about how gases move.....Too big actually slows the exhaust pulse....
AZ

[Muleskinner]

Originally Posted by Azgoldrat

That crushing actually cause's the exhaust pulse to move faster and is quite effective.Venturi effect. Replacing the stock Y-pipe showed lower torque numbers and little to No HP gains....Ever see a Gas powered RV Exhaust?? Big 454 engine...Tiny exhaust pipes....Its all about how gases move.....Too big actually slows the exhaust pulse....
AZ

Right you are! I bought a custom Y pipe from Summit made from the same diameter tubing as the stock exhaust system and replaced the stock Y pipe with this one. I had to remove the resonater to build the system. The result, NO difference in the seat of the pants dyno.

I also just removed my Custom Chrome headers (AKA the same design as JBL) and reinstalled the stock exhaust manifolds. Again, NO difference in the seat of the pants dyno. Go figure. I think Toyota really did their R&D on this system.

I now have the stock exhaust system, except for the custom Y pipe and the truck runs just as good as it did with the headers. What a waste of time and money that experiment was!

This is a small CI V8 guys and if you take away a lot of the back pressure in the system, stand by for a big low end torque loss. Originally I had the TRD dual system on it, along with the headers and the Y pipe. I got rid of the TRD system within 4,000 miles. That system robbed a HUGE amount of low end torque. Once I put the stock exhaust system from the Y pipe back back on, I picked up all of my lost torque again. What really surprised me was the fact that when I put the stock exhaust manifolds back on, the engine ran no different than it did with the headers.

I think the only way to gain torque with this engine would be to have a custom set of long, small diamiter primary tubing, equal length headers designed and built for this application. Then continue the system rearward from the header collector with a small 2" diamiter exhaust pipe all the way to the rear of the truck. Duals would be okay, but any pipe over 2" diamiter will kill the low end torque. Pick the muffler of your choice.

[Burger Steak & Eggs]

Originally Posted by Azgoldrat

That crushing actually cause's the exhaust pulse to move faster and is quite effective.Venturi effect. Replacing the stock Y-pipe showed lower torque numbers and little to No HP gains....Ever see a Gas powered RV Exhaust?? Big 454 engine...Tiny exhaust pipes....Its all about how gases move.....Too big actually slows the exhaust pulse....
AZ

Can we see these dyno results?

[Burger Steak & Eggs]

Originally Posted by Muleskinner

Right you are! I bought a custom Y pipe from Summit made from the same diameter tubing as the stock exhaust system and replaced the stock Y pipe with this one. I had to remove the resonater to build the system. The result, NO difference in the seat of the pants dyno.

I also just removed my Custom Chrome headers (AKA the same design as JBL) and reinstalled the stock exhaust manifolds. Again, NO difference in the seat of the pants dyno. Go figure. I think Toyota really did their R&D on this system.

I now have the stock exhaust system, except for the custom Y pipe and the truck runs just as good as it did with the headers. What a waste of time and money that experiment was!

This is a small CI V8 guys and if you take away a lot of the back pressure in the system, stand by for a big low end torque loss. Originally I had the TRD dual system on it, along with the headers and the Y pipe. I got rid of the TRD system within 4,000 miles. That system robbed a HUGE amount of low end torque. Once I put the stock exhaust system from the Y pipe back back on, I picked up all of my lost torque again. What really surprised me was the fact that when I put the stock exhaust manifolds back on, the engine ran no different than it did with the headers.

I think the only way to gain torque with this engine would be to have a custom set of long, small diamiter primary tubing, equal length headers designed and built for this application. Then continue the system rearward from the header collector with a small 2" diamiter exhaust pipe all the way to the rear of the truck. Duals would be okay, but any pipe over 2" diamiter will kill the low end torque. Pick the muffler of your choice.

Seat of the pants impressions may not be accurate for small changes. Do you have any dyno or dragstrip results to illustrate these claims?

Low end torque losses are attributed to engine controller induced overly rich conditions after bolt ons were installed. See Thundera's posts. He leaned out his mixture with a URD device and achieved substantial increases in low end torque...with bolt ons in place.

[Azgoldrat]

Do a Search of this site this was beat to death along time ago.
Search topic's...
JBA
Y-pipe.
Magnaflow
One of the modiators did dynos and such and the results blew many out of the water I think it was Rockymtnray??? he used to cover the Towing forum.

The results surprised everyone at the time.

[H2O_MAN]

Originally Posted by EcHo

i remember back in the day someone actually took a lot of brands and had them dynoed and found the best combination for headers and exhaust for extra power. does anyone remember these?

I don't remember the Dyno results, but the best combo I have found is headers from JBA and the stock exhaust system