3.0 crossover pipe swap out!!!!
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3.0 crossover pipe swap out!!!!
I've heard over and over that the crossover pipe on the 3.0 is a huge killer to the engine, and seeing diagrams of the pipe and exhaust flow through it, i can tell it is a terrible set up. But what i was wondering is if anybody has removed the crossover pipe and adapted new piping down to the cat . seams to me that would give tons better flow. If anyone has done this could you give me some info on it. Thanks
#2
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If you could get around the space issue, you would have to block off the port that the crossover dumps into on the drivers side manifold somehow. Welding a plate over it would work fine. Other than that, you'd have to remove the crossover completely and either modify it so it'll point down along with the current downpipe or fashion your own pipe to run to the passenger side manifold that'll fit through as the crossover did. That's a lot of work... just get headers.
Actually, from what I've heard... the engineers that designed the crossover this way weren't as stupid as we all think. There's actually no restriction from having the crossover pointed the way it is. Something about how the cylinders fire and the pipes being tuned specifically for that. If you've ever seen the crossover, it's got a big bulge in the middle of it, and I'm pretty sure that bulge is for tuning purposes.
What you need to do is just get new exhaust piping from the downpipe back. 2 1/4" should work great. Match that up with a high flow cat and muffler, and you're set. Or at least that's what Tim at DOA says.
Actually, from what I've heard... the engineers that designed the crossover this way weren't as stupid as we all think. There's actually no restriction from having the crossover pointed the way it is. Something about how the cylinders fire and the pipes being tuned specifically for that. If you've ever seen the crossover, it's got a big bulge in the middle of it, and I'm pretty sure that bulge is for tuning purposes.
What you need to do is just get new exhaust piping from the downpipe back. 2 1/4" should work great. Match that up with a high flow cat and muffler, and you're set. Or at least that's what Tim at DOA says.
#4
By removing the CO pipe you will gain flow & HP IMO. By removing it you can also then have a true dual exh. instead of single into duals. MikeT223 was going to do this mod but got busy on other projects. He was going to from the sounds of it yank the CO pipe, port the exh ports, and turn the 3.slow into the whoaaaaaaaaaaaaaaaaa lol. I am going to see if I can pick up the 3.0 exh manifolds tomorrow when I pick up some other parts. If I get them that may assist him with his experimenting. I just dont see how some can say it will not help. flow traveling into direct flow is for sure going to hold it up. No off. Churnd.
Also I have a buddy that has this mod done to his 4runner but it came that way when he bought it. So atleast we could have a model to copy from if Mike is willing to be the doctor on this operation. lol
Also I have a buddy that has this mod done to his 4runner but it came that way when he bought it. So atleast we could have a model to copy from if Mike is willing to be the doctor on this operation. lol
#6
Originally Posted by carose725
can you get some pics of his modded crossover pipe for us. i think it could be very benificial to many 3.0 owners if this mod were visible.
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Hey Carose, sorry to hijack the thread but I got a question bout your exhaust set-up. I too have a 93 runner and looking to upgrade the system. As you already know the stock pipes are all 2" and Iam thinking of doing what you did. ie. from headers to tailpipe convert to 21/4" Including cat and muffler. Thinking of going with a Walker High-flow cat and the Dynomax super turbo muffler. I guess the question is do you have any advise on this and how do you like the set-up? BTW. really good idea with the cross over pipe. I thought bout that one too. But I gotta take the mods slow. You know, dont wanna lighten the wallet too much too fast. Later, Lee
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My exhaust !!!
Originally Posted by 4Runner 4Play
Hey Carose, sorry to hijack the thread but I got a question bout your exhaust set-up. I too have a 93 runner and looking to upgrade the system. As you already know the stock pipes are all 2" and Iam thinking of doing what you did. ie. from headers to tailpipe convert to 21/4" Including cat and muffler. Thinking of going with a Walker High-flow cat and the Dynomax super turbo muffler. I guess the question is do you have any advise on this and how do you like the set-up? BTW. really good idea with the cross over pipe. I thought bout that one too. But I gotta take the mods slow. You know, dont wanna lighten the wallet too much too fast. Later, Lee
#10
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Originally Posted by BigBadBlue
By removing the CO pipe you will gain flow & HP IMO. By removing it you can also then have a true dual exh. instead of single into duals. MikeT223 was going to do this mod but got busy on other projects. He was going to from the sounds of it yank the CO pipe, port the exh ports, and turn the 3.slow into the whoaaaaaaaaaaaaaaaaa lol. I am going to see if I can pick up the 3.0 exh manifolds tomorrow when I pick up some other parts. If I get them that may assist him with his experimenting. I just dont see how some can say it will not help. flow traveling into direct flow is for sure going to hold it up. No off. Churnd.
Also I have a buddy that has this mod done to his 4runner but it came that way when he bought it. So atleast we could have a model to copy from if Mike is willing to be the doctor on this operation. lol
Also I have a buddy that has this mod done to his 4runner but it came that way when he bought it. So atleast we could have a model to copy from if Mike is willing to be the doctor on this operation. lol
None taken. I'm all for finding more power, and I applaud those who have the guts to try something new.
I hate to be the voice of doubt, but I still don't think it's gonna work, unless you've got plenty of money and time to fool with it.
Now about that running pipes off of each manifold as duals... why? I don't see that being any more powerful as using a well tuned crossover, considering you match up the backpressure numbers for each pipe. Low end would be non-existant, it seems. I dunno... maybe it would work. But I'd have to see before and after numbers to believe it.
#11
Originally Posted by Churnd
None taken. I'm all for finding more power, and I applaud those who have the guts to try something new.
I hate to be the voice of doubt, but I still don't think it's gonna work, unless you've got plenty of money and time to fool with it.
Now about that running pipes off of each manifold as duals... why? I don't see that being any more powerful as using a well tuned crossover, considering you match up the backpressure numbers for each pipe. Low end would be non-existant, it seems. I dunno... maybe it would work. But I'd have to see before and after numbers to believe it.
I hate to be the voice of doubt, but I still don't think it's gonna work, unless you've got plenty of money and time to fool with it.
Now about that running pipes off of each manifold as duals... why? I don't see that being any more powerful as using a well tuned crossover, considering you match up the backpressure numbers for each pipe. Low end would be non-existant, it seems. I dunno... maybe it would work. But I'd have to see before and after numbers to believe it.
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hey guys, i've got another exhaust question. I've got a 3.0 and I was thinking about maybe running 2.25" pipe from the down-pipe back a few feet into a flowmaster or magnaflow, then have maybe a turndown or something. I do not want to run a cat b/c by law you don't have to run one in Alabama(that's where my truck is tagged). I did this on my '86 22re 4runner and could tell a nice difference in power without the cat. I also want the turn-down b/c I like the look with no exhaust pipe. It worked very well on my '86. The main question that I have is, if I put the o2 sensor in the same location on the new pipe, will the truck still run correctly? i think that if it runs right, that would be one of the best increases in power that you could get from a 3.0 exhaust.
#13
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Originally Posted by blackrunner91
hey guys, i've got another exhaust question. I've got a 3.0 and I was thinking about maybe running 2.25" pipe from the down-pipe back a few feet into a flowmaster or magnaflow, then have maybe a turndown or something. I do not want to run a cat b/c by law you don't have to run one in Alabama(that's where my truck is tagged). I did this on my '86 22re 4runner and could tell a nice difference in power without the cat. I also want the turn-down b/c I like the look with no exhaust pipe. It worked very well on my '86. The main question that I have is, if I put the o2 sensor in the same location on the new pipe, will the truck still run correctly? i think that if it runs right, that would be one of the best increases in power that you could get from a 3.0 exhaust.
I say try it... it doesn't cost anything. If it doesn't work out, weld in a high flow cat and that'll be the answer to your problems.
With mine, I didn't have enough back pressure and for some reason my idle fluctuated erraticaly a lot.
#15
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Originally Posted by blackrunner91
Churnd, hey man, so you're saying that your truck ran good with no cat? what did you do to fix the eratic idle?
#16
Originally Posted by blackrunner91
Churnd, hey man, so you're saying that your truck ran good with no cat? what did you do to fix the eratic idle?
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okay, here's what i'm thinking now:
from downpipe use 2.25" pipe back to a high-flow cat, then either a flowmaster or magna-flow or other, then a turndown immediately after muffler. sound okay?
from downpipe use 2.25" pipe back to a high-flow cat, then either a flowmaster or magna-flow or other, then a turndown immediately after muffler. sound okay?
#18
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Originally Posted by blackrunner91
okay, here's what i'm thinking now:
from downpipe use 2.25" pipe back to a high-flow cat, then either a flowmaster or magna-flow or other, then a turndown immediately after muffler. sound okay?
from downpipe use 2.25" pipe back to a high-flow cat, then either a flowmaster or magna-flow or other, then a turndown immediately after muffler. sound okay?
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How Bad Did It Get?
Originally Posted by Churnd
No, I meant it ran bad with no cat. No backpressure and the idle fluctuated. You could hear the exhaust pinging around in the pipes if you listened close enough. That noise was a telltale sign that I needed more backpressure. It was fine for high end, but I don't race.
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Originally Posted by Churnd
Actually, from what I've heard... the engineers that designed the crossover this way weren't as stupid as we all think. There's actually no restriction from having the crossover pointed the way it is. Something about how the cylinders fire and the pipes being tuned specifically for that. If you've ever seen the crossover, it's got a big bulge in the middle of it, and I'm pretty sure that bulge is for tuning purposes.