BBrown

I'm thinking about putting some headers on my 3 generation 4runner but I have some questions that I would like answered. I have done some research but I would like someone's opinion based on experience. First, do headers add very much power? Second, what is the downside to headers? Third, is it a job that you can do on your own? Fourth, about how much will it cost in the end? Last, any suggestions about what kind to buy. Thanks

4-RUNNIN' FREAK

When I had my TRD headers and exhaust put on, I noticed a big increase in throttle response. Hit the gas and the RPM's jump quicker.

A downside I learned from YT is increased temps under the hood.

YOu can do it on your own, but the cross pipe is a PITA. I had Toyota put 'em on, and the fact that they ordered the wrong cat back when I gave them the numbers, took them two weeks to install.

The TRD headers also have nice beefy flanges where they meet the block. Not like on some other brands I have seen on Yotas.

javadoody

i just put nwor headers on last summer, got 'em on ebay for around 125(?). did it to improve pull up the passes out here in the winter (i board). yes, i noticed an increased pull, i had also modified the airbox (my own approach) and fitted with amsoil filter prior. now i can pull in 4th what i had to rev in 3rd. at the highest incline over the passes, strong solid pull in 3rd instead of screaming in 2nd.
i haven't noticed any decrease in mileage, still get 26+ on the highway crusin at just under 3000. around town my foot tends to be into it more, sounds good and there seems to be a bit more pickup (flowmaster + 2.25" going on next).
easy install, just remember to replace the nuts. use a good sealant (mine didn't have any gasket). spray the heck out of everything with wd40 the night before and it's a half-day job.
best investment so far.

wimpywade94

1/2 day job turns into even more with the 3.4 though, It can be done yourself but i would pay to get it done.

wade

4-RUNNIN' FREAK

Just want to add that with only the headers and cat back I was getting about 22 MPG in cruise at an average of 75 MPH.

Almost made it to Canada from New York on one tank of gas, and probably could have stretched it, but didn't want to chance running out of gas.
I was cruising at 95 for awhile down the NY State Thruway for at least 60 miles. It was in winter with the oxygenated gas.

init6

I just put some TRD headers on my 3.4L tacoma this weekend. What a PITA.

FilthyRich

you like??

init6

It does have an improvement in throttle response. I do have a slight leak were the header flange meets the cat. Since it's not my DD, I'll figure that out next weekend. Since I picked them up used, it was not a bad deal. If you are going to do a self install, have patients, and expect the unexpected.

zman2day

I agree. The TRD header installation is a major pain..but doable with ALOT of patients. Luckily I have a 2inch body lift which I think made it MUCH easier concidering the place the Y-pipe connects. I believe most end up cutting up the OEM exhaust manifold to get it out..with the body lift I got it in the sweet spot to remove it without cutting. In my opinion,TRD does make the best set of 3.4 headers yet..Edlebrocks end up going under the oil pan (rock catchers)....although the TRDs are more prone to leaks if not extremely carefully installed. Torque specs followed to the "T". I have had to remove mine once already because I rushed the first install and had leaks.

Now on to the important stuff... much improved power and hi end torque
(2500+) and some low end torque loss (1000-2300 or so). Would I do it again....yes...spend the $900 or so.... no. but to be honest I didnt spend that much...long story there. maybe for another post. Not sure how much your planning on spending but it is quite expensive all around if you dont get a smok'n deal on them.(in my opinion) Edelbrocks are cheaper though. I remember some old members on the wire with them. Chad Burton (NOTRUB) sold his 3rd gen last year though and (Wyatt) maybe he or others have something other than TRDs.

midiwall

I installed Downey headers a while ago, before I had done much to the truck. At the time, I had done the Deckplate Mod, the ISR mod and had installed a SMT5 piggyback ignition/fuel controller.

Given that... It was a waste of money. The headers created a bit more torque down low, but not enough to make up for the end cost of about $700 (headers + install). The install on the 3.4L is a PAIN - there's a LOT of work to get rid of the stock crossover pipe, getting the stock manifolds out is no easy task, and getting the headers on themselves is a BEAR.

Now... fast forward about a year when I put a supercharger on. THAT is the time that you want headers. OMG! With more air coming in the top, you NEED to be able to get that spent air/fuel OUT, and that can best happen with headers.

In the end, I'm glad that I had the headers on when I put the S/C on - spreading the combined cost of the two pieces (and associated gear for the S/C) across a year is helpful. In hindsight, I would have skipped the headers up front, though I'd be dreaming about them now with the S/C!


Brand wise... Personally, I think that you're looking at the split between 5ish HP across brands. I would shop price more than header brand. There _is_ a difference in fit, and a lot of guys talk about the great fit of the TRD's - though again, no matter what, it's a bear install.

A tip for the install is to use the STOCK exhaust manifold gaskets - NOT the TRD's or anyone elses. The best fit/leak ratio that I've seen comes from the stock gaskets. It seems that the 3.4L header install is one of the worst in terms of leaks.