Thrillbilly

My exhaust system is starting to rust through and I need to replace the whole thing some time soon. Its a '98 4runner with the 3.4 L engine. I was wondering what kind of options there are out there for exhaust systems and headers, and what a good combo would be. Any input would be apreciated, thanks in advance.

YodaPala

Don't bother with the headers waaaaaaay too expensive plus they are a pain in the a$$ to install. I heared some good things about the jardine cat-back set up for 3rd gens, Thats the exhaust I look foreward to when the time comes.

Elton

no need for headers unless your s/c and jardine has exhaust kits pretty cheap

97Limited

I have installed the TRD Headers with a full custom Magaflow exhaust on my 97 4Runner.

Yes the Headers are expensive and a pain to install, but with my set-up I did notice a gain in Throttle Response, and some low end torque!!

Thrillbilly

Anyone have a link to look at the Jardine exhaust?

midiwall

Interesting... You're the first person I've heard say that who wasn't SC'd. They screwed up my performance something awful when I put them on pre-SC.



Performance Products sells 'em:

http://www.performanceproducts4truck...brand&bid=1795

97Limited

[QUOTE=midiwall;50467148]Interesting... You're the first person I've heard say that who wasn't SC'd. They screwed up my performance something awful when I put them on pre-SC.

Well there could be other reasons for this!! I only run 90 octane or better (ethanol blend) in my truck, Proformance Wires, Deckplated with TRD Filter, ISR mod, Full cat-back Exhaust. And I clean my Injectors at every oil change.

midiwall

'k... I was in the same boat, with the ECT mod and an SMT5 piggyback as well.

Hugo

Headers HURT your performance???

midiwall

Yeup. And it's been talked about here before by other folks as well.

Keep in mind we're talking about the 3.4L, not the 3.0 or 2.2 where even tying a coffee can to the end of a piece of galvanized pipe would help them.

In my case, I put on headers and a full cat-back with 2 1/2" pipe. The issue became that there wasn't enough back-pressure to create enough scavenging, and the exhaust cycle left crap in the cylinder, robbing power.

In addition, the headers dropped the onset of the power band by about 800rpm. That's great for a SC engine, where the power comes on earlier, but not NA.

Bottom line, the truck ran like crap.

wa4x4

I welded in a 50 series flowmaster 2.5" onto my stock piping. But, my pipes weren't rusted so this probably doesn't help you at all.

97Limited

Not In all Cases!!! Mine did not 'hurt' Performance at all!!

And there were 3 Different Headers made for the 3.4L!!! I'm running the TRD Headers!!

midiwall

The header designs are all very similar... Similar enough that your result is very strange...

97Limited

Downey headers have the crossover pipe under the tranny!!

And the TRD's are more like the stock manifolds which the crossover pipe goes over the tranny!!

midiwall

Right, but we're talking about the header, not the crossover. Plus I'm talking about HOW the headers flow, not WHERE they flow.

n/m... "your mileage may vary".

geez

Hugo

That's very strange that a performance product would hurt it. Not doubting your claims, just saying...

Oh well, one less expense.

midiwall

Headers are made for the situation where you need to move more volume out of the cylinders. On a NA 3.4L the stock manifolds are fine - it's not the same as on a 3.0 or 2.2.

With the bigger piping and more efficient flow through the headers, then on a NA engine, you're reducing the back pressure which will reduce the scavenging, which is a natural effect that helps get the exhaust out of the cylinder.

If you throw the SC into the mix, everything changes... The headers will unlock 30+ HP and about the same in torque and push the powerband down to where the SC really starts to shine.

Hugo

It's funny because on BMWs, headers are a proven way to get some HP, both in regular and cammed N/A situations. But not all headers are ok for forced induction.

Goes to show that all engines react differently.

midiwall

Yeup... And I said that above, or in some other thread about this point.

The 3.4L is not a typical engine when it comes to exhaling. It's not a 6.0L diesel that will actually handle a 5" exhaust; it's not a large block Chevy that will handle straight pipes..

You have to treat ANY engine situation as unique. It's simply not valid to take something that you learned on "A" and apply it to "B".


Thanks for the babble...

ornery

I find it interesting that you say headers hurt the performance.. I'd like to see some dyno results to prove that..