ISR mod is awesome!!!
 

Well I got the isr mod done yesterday, big thanks to Christian <96 Runner> who helped me with it at our little az meet. Took him only 5 minutes with all the parts already. First drive out, punched it, WHOA!!!!! Now that is loud!!! But it isn't annoying loud, it's more of a beefy loud. I don't really see how people can get annoyed by the sound, I think it sounds great, with an aftermarket exhaust it'll probably sound even better too.

The only draw-back is running premium, it's sorta pricey out here at $1.71 / gallon, but I feel it's worth it. However I am gonna put the intake silencer back on in a week and run regular again because I have a huge road trip I have to make. But once I reach my destination, it's coming right off again.

Big props to both Christian, for knowing about this mod a looooong time ago, and Dr. Z for making it known and also creating it. :welder:

A definite must to at least try it out. :drink:

Umm, you have to run Premium gas with this mod? I must have overlooked this when researching it. Ive yet to do the mod but have been planning on it for the early summer. What will happen if I keep running regular or mid-grade?

i want to do this mod too, but also failed to know about the premium gas thing. also, anyone from the Atlanta area want to help me out with it???

Prolax,
From what I've read, it will make the engine ping. Apparently this thing makes a huge difference in the amount of air going into the engine. I want to do it, I'm just concerned about the sound. Seems to me like it will be loud as hell.

Matt

Yea from what I heard, regular unleaded does make it ping, however I think there is a member with this mod on a taco that's running 87 octane and isn't pinging. Don't remember who though.

Matt the sound isn't THAT loud. I think it sounds awesome. It only cost me 7 bucks and 5 minutes. I think it's AT LEAST worth a try. Real easy to reverse.

Im running 87 on my 99 with ISR and Deckplate. No pinging.

I did the ISR mod yesterday. It si more of a more prominent growl from the engine than it is noisy. On my 88' it just sounds like I have a better motor than I do:P .

I have only had it a day, but I am not running premium, and it is running just fine. When my tank is empty, I will try premium and see if there is any difference.

What is the logic behind needing premium with this mod anyway? Dr.Z?

I'm guessing since you're removing the intake silencer, also other empty compartments that trap air on the intake, it lets the air go straight from the airbox to the motor without getting trapped anywhere. So with the extra air coming in, the octane of the fuel should be higher for a more powerful combustion? Maybe....

Just a guess

Hmm...I might try and run regular 87 and see how that goes.:dunno:

I did this mod last Oct. and have been running nothing but 87 in my runner with no pinging problems.

Just got back from a trip today which included steep climbs to 6,000 ft and still no pinging. I've never run premium in mine.:dunno:

Mick

I saw Christian install the mod. The runner is quite a bit louder now. I would say no louder than when I installed the deckplate, however.

Not as loud as a supercharger, that is for sure.

I'm going to try this next week. I have tested my EGT with and without the deckplate and I get 1525 as the hottest temp under both conditions. (so I'm just slightly lean I think)

I'll post my ISR results next week when I get some time.

Dan

Isr mod?
 

sorry if I sound like a newbie when I ask this.
I've researched all kinds of stuff about toyota
trucks, so I do know a fair amount about them.
not to mention Ive done clutch changes and timing
chains in 22re's, but what is the ISR mod, and
can it be done in a 2nd gen runner with a 3vz
:chairfall

Re: Isr mod?
 

See Here:
Click it! You know you want to!

Here's the beef...
 

First the premium fuel issue:

Many of us have experienced a lean condition at some RPM's with the ISR mod. You have to REALLY listen for it due to the enhanced growl of the ISR mod with the deckplate open. Because we are messing with the FPR (Fuel Pressure Regulator) and removing all baffles on the intake (streamlining the airflow), some engines are leaning out. Running premium fuel (burns longer) allows for more complete combustion during the compression stroke, thus reducing the chance for a "flame-out" (pinging).

I truly believe some are not experiencing pinging. However, this may be directly attributed to the knock sensor doing its job. When pinging (well knocking, which is worse) is detected, the engine retards the timing to prevent damage. I feel this is happening on some engines where premium is not being utilized. Therefore, performance potential is not being realized completely.

Run premium. My .02.

I second 96_Runner.

Dr. Z

:yawn:

Re: Here's the beef...
 

Very well put!! Looks like I might stay with premium instead. :drink:

FWIW, if you're at altitude like I am in Denver, you will not need premium. The air is thinned out here enough that even with all the ISR and deckplate mods in the world, you will never be at sea level air pressure where the engine is designed to run, so it's no big deal to run 85 octane gas like I do (no pinging, I listen real close).

Maybe at low elevations you need it. But it does not give you more powerful combustion as one person suggested it might, higher octane = slower burn like 96_runner pointed out. If you are pinging and the knock sensor is retarding the engine, it will help, but in a truly non-knocking (i.e. not modified by the computer) engine the premium gas will actually hurt performance.

Not sure what the elevation is in AZ where you are, but it might be low enough that you need higher octane gas with these mods. Though in AZ I would think 87 octane would be fine...

Denverbikeguy, we are generally Sea Level to 1000 in the PHX area. So, altitude is not a factor. However, heat just might be.

I agree, at higher elev such as denver, normal fuel will suffice. In fact, when I go up north for camping, I plan accordingly by running lower octane. Saves money and makes sense.

Good points.

Can someone post an audio clip so those of us who aren't ISR'd can see how loud it really is inside the cab?

Matt

Before

After

Above links courtesy of (College Boy) RTDawgs. :)

Dr. Z

PS Matt, just get off your ass and do the mod already! :bounce2:

Dr Z,
I am going to. Just wanted to hear it first. I've got a monster hill to climb coming from work and another monster mountain before I get home. I've got a feeling the engine will ROAR after doing this mod when climbing these hills. Have I touched a nerve with you Doc? :) Just kidding. Later.

Matt

I just realized those links don't work. Ryan? Why are they broken? Did you take the vids down for some reason?

Oh well, maybe he'll fix them. I'll shoot him an email.

And Matt, I was just messin' with you. :)

Dr. Z

:bang: I just had to reread that post that said premium was kinda pricey at $1.71 a gallon. I just came from the gas station in which my wonderful 93 runner averaged just shy of 15mpg. I filled up with 87 octane at 1.87 a gallon. I think premium 91 octane was going for 2.15 or something like that. Gotta love the bay area!

Mid grade here in Phx is around the 1.71 mark. 91 octane premium is around 1.81

I bumped this because it's worth looking at how easy it seemed to complain about having to pay under $1.71 for premium. My how times have changed.

what a blast from the past....its amazing how times are changing. mainly because:

a - the aforementioned price of premium
b - i actually recognize the names in this thread
c - i no longer have a toyota.

The only draw-back is running premium, it's sorta pricey out here at $1.71 / gallon, but I feel it's worth it.

whoa that is pricey lol :lof:

I'm going to buy midgrade gas tomorrow, for the first time, as I have the ISR mod, we'll see, looking for improved performace....Cost of a gal. today is $3.68

I think you guys are smoking some funny stuff.

I did this on my 97 Runner motor swapped into my 92 and didnt notice anything different other than it was a tad louder. I ended up putting the stock resonators back in.

Good experiment but in the end it was a waste of $8

Helps to reset the EGR
 

fuse afterwards. Best benefit from this mod is improved throttle response.

screw the mod.. did you see how much fuel was back in 03??

thanks corp america!!

rant off :)

This whole thread is funny :).

wow, you know this post is old. $1.71 is pricey?? welcome to 2011..... haha

since the thread is back...

I was talking to a mechanic today, he said the ISR box also served as a place to hold vacuum back-pressure, and is used during deceleration to prevent stalling.

Can anybody comment on this?

Dang... $1.71 just back in 2003....

Still can't believe how long ago 2003 was now... Man life just goes by way too fast...

I have done both the ISR and the deck plate and have been running 87 in MN/WA down to 85.5 in MT and WY and have never noticed anything that sounded like a ping or a knock. It has been about 2 years since I have done the modifications. Maybe I am just lucky but I haven't had any issues. Even at altitude driving across CO and WY and the passes in WY and BC, my mileage has been around 16-20 @ 60-65 mph depending upon incline and weight in the truck.

Intake modifications?
 

really curious about all the intake mods. I know its been talked about way to much. And I personally have some of the mods and are happy with them. But was just wondering if anybody really know why toyota didn't do this themselves. Mods that improve on MPG's and power\ or just throttle response. But any improvment is good, not bashing here. Why wouldn't toyota want to add horsepower and MPG's with something as simple as throttle body spacers, or more air flow to the air box (deck plate), or intake silencer (known as torque destroyer? Could it be just as simple as a small sacrifice in those areas for massive noise reduction, and or less mantanience of an air filter. Not to mention that we all know throttle body spacers must be a scam, because know one can actually tell you they work. All speculation. (show me results, oh u can't) ok . If i cut a giant hole in my air box and got better MPG's and more power, which i truly feel that i did, and the only downfall is extra noise. Then I'm happy with that. Long story short, why is this the way it is? As an auto manufacturer the last thing i would do is drop any power or MPG's. Unless a tiny improvement meant a big drawback somewhere else. :ontopic::rant:

Here's the skinny... Th intake restrictions are for smog and emissions. The above mentioned mechanic was trying to sound smart or may have know of a vehicle in the past that the intake held vacuum for... but that sounds like hooey to me... Not sure I spelled that right.... But yes it will help with throttle response and with wide open throttle. It's not much louder and it's basically the equivalent to cutting off the cat for the intake... If you haven't done it... You should. And you shouldn't have to run Premium... That may depend on what altitude your at as well... Also it should help with MPG's if you can kep your foot out of it... It will hurt if you have a heavy foot. I'm in the South and have but thousands of miles on this mod without fault. I do not have the deck plate mod though...

I could see that being a major reason for all that crap under the hood. Makes ya wonder what else be simply removed to gain something. But research in one hand and wonder in the other and see which on fills up first uh. thanx for your imput.

Having worked as a dealership tech for many years now, it is amazing to see what lengths the OEM's go to, to make a vehicle quiet, smooth and non-responsive (in a good way) for the majority of the American public.

That funny box on the intake just gives the air in the intake pathway a place to go and be absorbed when Bobby Sue lets off the throttle suddenly during a full throttle on-ramp run. Think shock absorber... that way the intake air sensor doesn't get all funny, the car doesn't buck, etc.

Now those of us interested in a vehicle with a little growl and a little more bite to it don't need that or even care about that. But not everyone's idea of "drivability" or "tolerable" is the same. I run a highly modified 91 Talon AWD that would drive some people insane.

On my 4runner, I've done the air box mod, I ported the metal throttle body gasket to match, I run the Airaid Jr intake, I fabricated a 2.5" stainless exhaust with an 18" Magnaflow and I love all of it. Every bit of it. It's only loud when you're full throttle, the throttle response is much, much better than stock. I would never go back to stock or tell someone not to do any of it, but some people won't like the 18" Magnaflow, or the growl from the air box mod, or the slight intake hiccup that happens just ever so slightly once in awhile when traffic doesn't cooperate with my previous gas pedal input. And some people just like to complain, whereas I want my truck to move. Heh. ;)

amen!