rimpainter.com

How did I miss this thread?

Anyway, since people are talking about me, and I really didnt know it, here it goes.

Its simple, quiet SUV's sell better than loud SUV's. Thus Toyota sacrificed some HP to quiet the intake track. Therefore we screw with the intake to get the HP back, and sound cool in the process.


It was the ISR mod, with the deckplate open the entire time. I also tested the ISR mod capped and uncapped with surprisingly good results. By the way, I am perfect, so it wasn't "DIYer" error.


Oh, and as for the gas mileage "problem" that others have listed. Well, for me, the MPG has not changed; I avg 17.3 mixed driving, before and after the ISR mod. Its all about the right foot action as others have mentioned. I have spreadsheets to prove this also, but hey what good would posting that do? After all I am the same guy "who drag race SUVs with a wrist watch in hand."

Tencast

Huh, it seems as though we are averagign the same milage in mixed driving condition. When I started this thread I was getting closer to 14 in mixed conditions but it seems to be improving. I guess we'll see.

Tencast--

Gbost

I just took the isr mod off my 02 taco afet three weeks and a couple of tanks of gas because while giving a little better response off the line with the pedal to the floor it seemed to drag a little after shifting . I put the box back on it runs great, for me the box stays on.

Greg

4RUNR

Well, the "really bored" happened more early than expected, tried the deck plate mod. Didn't feel any more power under 3k RPM, nor was it any louder. The ever so subtle wristling sound and that is all. Lets see what the MPG do now.

rimpainter.com

4RUNR-

So what you are saying is that you feel no power increase with the deckplate mod, nor the ISR mod? Is that right?

midiwall

...and what air filter do you have in the box? The stock Toyota paper or ???

williemon

Im feelin the love here.


I am a little concerned about this "troll" thing.

Biohazard

I've seen humidity mentioned a couple of times in this thread. Is there any data / experience that shows the effect it has on doing these mods? Do these mods possibly allow too much moisture into the throttle body in humid environments?

I only ask because we drink our air here on the east coast in the summer.

Tacoma Dude

In the ISR mod?
If I did mine correctly (I hope to God I did!), I have no exposed parts of the intake. Everything is as sealed up as it always is.

Deckplate probably different.
I have no info about that but if it hurts performance just pop the lid right on!

midiwall

Actually...

The other side of the ISR mod has been brought up from an angle of taking a look at just what each part of the silencer box(es) does/do.

One thing that's been said is that the "J" tube that hangs underneath the intake tube (on later models) is actually there as an evaporator and not a silencer or air distruptor per se'.

The thought is that excess mositure in the air (e.g., humid environments) will collect in the bottom of the J tube. Then, since the tube is situated over the manifold, it will evaporate fairly quickly.

With the folks that are complaining about losing powerand mileage being in humid climates, then maybe there's something going on that "simple" fluid dynamics isn't showing.


NOTE: From what I understand, there's a history of this debate on the forum. I'm not trying to dredge it up nor re-create it. It's just another angle of looking at the science of the pieces.

mchan77

Hey All,

I can tell you my experience

I have a 93 Runner with the 3.0 V6 and have been looking to get more power/mpg out of it since I bought it a few months ago. The first trip I took from Northern California to Southern California, the Runner barely made it up the steep part of Hwy 5 (the Grape Vine), it felt horrible as I am use to light small sport compacts with mods and turbos.

I did the 2.25" cat back first with the Dynomax ultra flow as suggested on this forum and it felt better. Then I did the modified ISR mod, drilled air box and scoop removal as suggested on the forum, disconnected the battery to reset the computer and it felt a lot better.

I just took a trip down to Southern cal for the 4th and although it still struggled going up the grape vine, performance was much improved. I also averaged right around 15-16mpg and that was doing pretty much 75-80ish the whole 400 mile trip. While not great mileage, it was equal to or better than what I got the first trip down there with the truck completely stock. (oh by the way, this was about 3 weeks apart). Over all the truck has 130K on the clock and it ran like a champ all the way down there and back.

rimpainter.com

Yeah, that's the N/A air-water intercooler. Common knowledge...

4RUNR

Yes, with just the deckplate mod and a fresh Toyota filter I did not notice any difference either way. The MPG is surprisingly high, about 20.5mpg on suburban roads doing about 40mph, not even highways, but it was like that before. The noise that I expected from all the descriptions is simply not there, but maybe because I keep it under 2,000rpm. It does feel like it's shifting earlier now, maybe 50rpm earlier, but that improvement can be written of as psychological. The mod staying on nonetheless.

rimpainter.com

Let's see...

Deckplate mod, ISR mod, fresh Toyota filter...no difference in sound or performance.

I give up man. You are one in a few hundred who havent experienced anything.

Next topic.

4RUNR

No no. Just the deckplate mod. No ISR, and the filer was new before the deckplate, so deckplate was the only thing changed.

Yes I'm that one in few hundred who doesn't lay on the gas like I'm driving a corvette :pig: to notice that much difference in air flow. Everybody floors it and wastes gas, but we all end up at the same light half a mile down the road. When will people learn :pat:

Maybe I need to reset the computer. No reason for me to embellish or understate anything. I "just" got this truck and would love to say it turns into a Ferrari when putting a few speed holes in it.

Yoter

:pat:

midiwall

If the filter is the STOCK factory Toyota air filter then it's VERY restrictive. Opening up a hole in the air box to allow more air into the air box doesn't mean it's actually getting to the _engine_.

Most folks are either running the TRD air filter, a K&N or Amsoil drop-in. Each of those is much less restrictive and allows the deckplate to make sense.

ManyMods

I do not disagree with this statement except that opening up the airbox does make a difference in the air intake even with the OE paper filter. Now YMMV and I must qualify by saying that I have the SC, but my experience has been that my performance did go down when I opened up the airbox, even with the paper filter in place. This is just a SOTP observation since when I opened up the airbox, after a while I could hear faint preignition and the vacuum reading went down. For me, the best combo has been the OE intake setup with the exception of the ISR.

rimpainter.com

I may have to disagree with this statement. A new paper filter will flow really well. Its when even the slightest amount of dust acummulates in them that the flow begins to suffer. I think gadget or someone had something on their site about the stock filter and its flow new.

Not trying to be argumentative, but thought I would point this out.

midiwall

Hmmm... I guess I was always under the impression that the stock paper won't pass any where ner as much air as the replacements I mentioned.

Obviously, I could be quite wrong. Thanks for speaking up guys.