2 1/2 inch exhaust

Mace

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perfect size imho..

noise will be determined by the muffler..
 

RockDoc

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I'm no expert on exhaust, but I would want to keep the down-pipes stock diameter to the first "element" (cats or Y or muffler) to keep velocity up and scavenging effective at the exhaust ports. Behind that, I would aim to minimize restriction to flow as much as possible.

My 0.02
 
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here is what we have experienced: Had a stock 2F with stock exhaust. Muffler was rusting out and hit by a few rocks, so we wanted to change it and gain the extra sound (maybe more power) by doing a cat back 2.5" pipe with high flo muffler.

So we did just that.

And...

Nothing really changed about the sound, and I could not tell a difference in power at all. The muffler shop guy pointed out to me while the exhaust was hanging out that the stock cats on the 60's are what really creates your back pressure, thus reducing sound and possible power gains that one would normally find with a cat back exhaust system.

Now once I got rid of the stock cat, that is a different story all together. Now she has more power and sounds KICK ASS!

I still have the stock exhaust manifold and piping up to where the stock cat was. from there it is all 2.5" pipe and a magna-flow muffler. We love it! :bounce:
 

serenity

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i have a 2.5 inch exhaust with headers, no cat just a muffler, i'm not sure how much power it adds on its own cos i have other engine mods too but its rather loud, and sounds great.

having never driven another 60 series i cant compare apples with apples but i have to say that my 60 is still my favourite car to drive and has a surprising amount of power.
 
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if i get the exhaust system, which i believe is pretty fairly priced. i might just take off the cat converters all together and just get like a magnaflow or flowmaster muffler. my dad is active duty, and i dont need to get my car inspected, ever,;) so i may just do that. get more power, and better sound. and the fact that it comes out behind the rear tire, rather than under the bumper...wont hit rocks other junk. :D
 

BlueCruiser84

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I have the stock cat with a 2.5 inch straight pipe after that. It sounds sweet and it cost like 70 bucks. I didn't notice any power gains.

I chose to keep the cat to have that added back pressure so I didn't lose any low-end. I don't really care about high end power because, let's face it, it's a landcruiser, not a race car and i can't remember the last time I really opened 'er up.
 

RockDoc

I'll take Bruce Vilanch for the block.
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if i get the exhaust system, which i believe is pretty fairly priced. i might just take off the cat converters all together and just get like a magnaflow or flowmaster muffler. my dad is active duty, and i dont need to get my car inspected, ever,;) so i may just do that. get more power, and better sound. and the fact that it comes out behind the rear tire, rather than under the bumper...wont hit rocks other junk. :D

Sounds like what I have for mine, except mines a cheapo muffler. The cats were deleted before I got the truck.... When I replaced the old muffler I found a side to my 3FE I hadn't seen before. Before it used to crap out ~2800 - 3000 rpm, now it will climb smoothly as high as I am comfortable pushing it.
 
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header (going back to stock exhaust soon) cat delete 2.5" exhaust from header to 40 series flowmaster.

quicker throttle response great range of power all the way through to upper rpm range.

kills my last sixty with high flow cat and stock exhaust.

makes a difference period.
 

RockDoc

I'll take Bruce Vilanch for the block.
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For the 3FE, the manifolds are said to be quite good themselves. The MAF headers don't seem to yield consistently good results.
 
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Nothing really changed about the sound, and I could not tell a difference in power at all. The muffler shop guy pointed out to me while the exhaust was hanging out that the stock cats on the 60's are what really creates your back pressure, thus reducing sound and possible power gains that one would normally find with a cat back exhaust system.

Now once I got rid of the stock cat, that is a different story all together. Now she has more power and sounds KICK ASS!

I still have the stock exhaust manifold and piping up to where the stock cat was. from there it is all 2.5" pipe and a magna-flow muffler. We love it! :bounce:

I have headers and a 3 inch flowmaster cat-back. I have a friend that works at a exhaust shop that can get me cats at a discount. So my question is what kits cat are you running?
 

serenity

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odd how you guys all have problems with leaky headers, has anyone investigated the cost of having some fabricated by an exhaust shop? i'm pretty sure mine were custom made and they fit well and have no leaks, although they are a little rusty but who cares its a cruiser.
 
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my main prob i have been having is the mount point where the intake used to have bolts that snug the intake manifold in the bottom center section.

with the header you no longer have that option.

i am in the process of doing a tbi system on the truck and i cannot afford to have any leaks there.
 
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I have never had any problems with having leaks around the gasket area and I have had the headers on for about 4 years now. I have the bundle-of-snakes the man-a-fre sales.
 
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I have headers and a 3 inch flowmaster cat-back. I have a friend that works at a exhaust shop that can get me cats at a discount. So my question is what kits cat are you running?

I don't have a cat. Got me some straight pipe baby! [announcer voice] ASK FOR IT BY NAME! [/announcer voice] :D:lol::lol::D
 
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The 3fe manifold is quite efficient however i have heard good things on 2 inch and 2.5 inch exhaust. Mine is duals 2 inch. I wish i would have just went with 2 inch from the manifold(factory is 1 and 7/8's) then ran them together then the rest of the way 2.5
 

Trollhole

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The 3fe manifold is quite efficient however i have heard good things on 2 inch and 2.5 inch exhaust. Mine is duals 2 inch. I wish i would have just went with 2 inch from the manifold(factory is 1 and 7/8's) then ran them together then the rest of the way 2.5

I sure wish someone made this section. From the mandolds into 1.
 
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Before tearing out the 3fe I had done a 2.25" exhaust with a new muffler (tossed the cat). Made little if any difference to what I remember...noise has more to do with the muffler.
The new drivetrain is 2.5" exhaust with a removable cat, and flowmaster 2-1 muffler. Vewwy vewwy nice sound.
 

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