Greedy

I finally have put enoufgh money aside for my next major 4runner purchase. I am trying to decide between the URD fuel upgrade kit or some trd headers. I would like to get urd kit first but the only problem is that I will have to pay to get it on the dyno and get it tuned again when I finally do get the headers. If I get the headers first and then the urd kit, i will avoid the doulble tuning cost but will prolong the pinging - lean issue with the engine and am worried about causing some long term damage. Any body have any opinons on this?

midiwall

If you're pinging now, then you need to get that under control, the longer it's pinging (and probably leaning out), the better chance you have of detonating your engine.

I just got done babbling a lot over in abother thread about my opinion on fuel mods and the like. I really shouldn't cut & paste it all into this thread, so I'll just point to it:
https://www.yotatech.com/forums/show...48&postcount=7

It came out of this thread:
https://www.yotatech.com/forums/f2/going-supercharged-stock-parts-needed-odds-ends-56018/


Header wise... the re-tuning after the headers go on is pretty straight forward. You won't really need a dyno to do it. The headers will open up some more power in the midrange, and push the torque curve down a bit. The S/C will basically run the same on the truck, it'll just have more of what it's giving you now.

Greedy

Thanks midiwall for the help. in your opinion, do the gains from the headers justify the cost? Also, do know of a good dyno/tuning shop in our area? I was planning on going to carb connection in totem lake...

midiwall

I get that question a lot, and even twice so far this week!


In short, since you're S/C'd, then yes, they're worth it. I started with mine when I was N/A and it was a mistake, but they make a very nice difference on an S/C'd truck. You'll find that the torque will come on a bit lower in the band, and the S/C will do more of what it's already doing across the same stretch.

Did you see my write-up of my header install fun? if not, check here:
http://www.midiwall.com/4Runner/headers.html


Tuning Shop wise, I've been to Carb Connection:
http://www.midiwall.com/4Runner/20040515_DynoDay.html

That was from a "Dyno Day" that I organized about a year ago. The old thread is here:
https://www.yotatech.com/forums/f2/seattle-dyno-day-31664/


They're good guys, but I was a bit befuddled by how they hooked up my truck. The charts I got that day showed a HP spike on the order of 360hp (or some such). Clearly bogus, but they didn't catch it and I didn't know enough to look until I was off of the ramp. No one else had a problem that day.

Their group rate was cool and they let us each go a couple of runs. I really want to go back for a full tuning, but the cash just isn't in the cards for me right now. The last time I checked, it'd be about $240 for two hours of tweaking (unlimited runs).

If you decide to go, then _BE SURE_ that you're comfortable with the tuning software (for the FTC-1 or whatever you end up using). It will save a TON of time on the dyno if you can quickly get around in the software and make fuel/timing changes.


What's your free-time like? I'm actually pretty close to you and would be happy to let you have a spin in basically your truck with headers and some extra tweaking. ooo, on 2nd thought, you're gonna hate my slipping tranny, but you'll get the idea. I need to get the valve body to John.

Greedy

I would like to take you up on that offer!! I am still debating on the headers or urd. As far as pinging goes, I can "make" it ping when under load but I can also make it stop by gassing it and making it downshift. I guess this is only the ping I can hear though and it may be doing it more than i know. I'll pm you and maybe we can figure a time to meet up and test drive eachoters rig. I actually got my valve body done by john already and it's set up to shift pretty hard. I like it though and might give you a good gauge when you send yours in. do you know of any dyno numbers that document the gain with and without headers??

midiwall

By all means drop me a PM or an email (mark@midiwall.com) and we'll figure something out - I'd like to see the IPT end result as well. I don't think I want a real hard shift, but I need something. eek.

Number wise, I haven't seen anything too real. A lot of folks toss around numbers like 50hp with the headers, but with it being so expensive to get before/after numbers, I don't think people bother after paying for the headers themselves!

Gadget has some dyno numbers online, but it doesn't cover header info:
http://www.gadgetonline.com/dyno.htm


Maybe something to look at is to do as much street tuning as possible (and I can help with that) and then get a few people together and do another group run on the Dyno. You can't really do tuning, but it'll help get you a baseline for a lot less $$$.

fwiw, I'd go with the URD kit - it'll help get as much as you can with the S/C and it's pretty painless to install (compared to the headers!).

My99

Speaking from pure theory, if you get headers you're going to open the exhaust more and allow the motor to breath more freely, thus leaning it out even more = more pinging. I'd go URD first.

midiwall

Good point!

northtorrey

Is that true? I scored a deal on the TRD headers (thru eBay) so I installed them without a S/C (which is still the plan). After replacing the MAF sensor and a very expensive O2 sensor, my check engine light still says it's running too lean. It's really bothersome, and I figure a S/C will only shove more air thru the exhaust and make it even more lean. Is the possible the CE light thinks its running lean from installing the headers alone? I even put the stock intake back on and that doesn't even matter... kinda frustrating.

My99

Interesting... I have no idea. Perhaps someone else with headers on an otherwise stock rig can help with some input as to whether this is common or an uncommon occurance.

I will say that my stock 1999 started pinging the other day pulling a light grade in 3rd gear at around 2,400 rpm while towing about 4,500 lbs. It was a warm day and I'd been sitting in traffic on the interstate prior to this hillclimb... but I was quite disturbed by this occurance. Of course running lean and pinging is not always the same thing. Running lean is not enough fuel. Pinging is from pre-detonation - fuel igniting before the spark plug ignites it. I think I could have simply cured mine with some higher grade octane, whereas yours I'm not so sure. Have you ever upped the octane to see if this would help your "lean" condition? I may be getting over my head now.

midiwall

It can be... The issue is that if the engine is able to exhale easier, then it can inhale easier as well. Now, the thing is that the ECU should compensate for the slight increase in airflow up front, and add more fuel as a result. But, things can go wrong, and the headers can make a bad situation worse.

On a N/A engine it shouldn't be noticable, but with the S/C pushing from the front, it can be bad.


Yes, this is true.


Ummm, no... I would think that something else is going on. Replacing the MAF and O2 sensor is pretty major (well, the MAF is) but there are more things in the path...

Clean/replace the air filter, check the TPS (throttle position sensor), clean the throttle body... There are other things.

What's the actual code that's getting set? There are a couple that can pop up, and the specific code can help you figure out what's going on. Also, what else has been done tot he engine lately? For example, did you change the plugs?

Something else... With the headers on, there will be more heat in the engine compartment, so it's important to get that heat away from the cylinders. If you don't, then the engine will tend to "diesel" which is where the cylinder will fire based on accumulated heat versus the spark. It's a long shot, but if that's happening, then it may be confusing the O2 sensor and thus throw a code.


oh... as an aside, the best price around on O2 sensors is from URD USA. It's an expensive device, but it doesn't have to break you.