So, I have the supercharger and the boost guage recently installed, and I wanted to test it out to see how much boost I was making. I drove while a friend read the guage. With overdrive off and ECT power on, at 105mph and 4800 rpm I made 8.5 psi! Pretty darn good! Then we got to a slight downward grade and it went to just under 9 psi. Then the limiter came on and it jumped up to 12 psi (due to the flow being slowed), but of course that wasn't a credible reading. I'm at practically sea level, and I have the ISR and deckplate mods, so I think I can attribute the extra 1.5 psi to those factors. It was definately an encouraging experience!

Zach

 

Careful man......don't kill yourself!

Good news on the boost reading tho.

 

Yeah, that's why I had the friend read the guage while I drove. It's still not sturdy obviously, and the steering feels really wobbly at those speeds, so I had to have both hands firmly on the wheel. I tried watching it and driving at the same time, but it was too dangerous -- I got scared glancing down at the guage going even 80. Oh yeah... we passed a cop who had stopped somebody on the side of the road, but we weren't speeding at that time.

Zach

 

That's like sucking on a loaded gun with finger on the trigger. Chances are small that it will go off, but one small mistake, and that is it. Don't forget, it's not a Porsche.

 

But it can sure as heck keep up with one.

 

Just to 3rd gear

 

A parked Porsche maybe

But in all seriousness the 4Runner feels and IS much more unsafe than a low to the ground sedan. I feel very queasy doing even 75 in it, I can't imagine having it if my commute was on the highway.

 

Mine is pretty comfortable and quite smooth all the way up to about 90 but that is all I am willing to go.....past that is makes me nervous that if something does go wrong, there is no way to steer out of it.....you're pretty much along for the ride! My dads Audi was smooth all the way up to 140 (and probably beyond) but the car is made to do that. Those big off road wheels are not z-rated tires so watch out when you bust a buck.

 

Yeah... 105 mph is not safe. I won't do that again, unless I'm like driving someone who's had a heart attack to the hospital. Even with the big-ass tires and the 3" or so lift, I'd say it handles smoothly up to 85 or so. I mean it obviously won't handle like a car, much less a sports car, but it's fine as long as you stay in a straight line. If you have to change lanes above 90 mph there had better be no one but you on the interstate! My dad has a 5-series BMW, and if you feel perfectly in control at even 120mph. Definately NOT so with the 4Runner! 120mph in his car feels like about 70 mph in my car. The tires are really loud at that speed, and when I had it dyno'd, I watched and the tire width actually shrank as the speedometer got above 60 or so,like you see when those long methanol-fed dragsters race. The height likewise got taller. Those are heavy tires too, with really heavy treads. So if you're going that fast you are probably 2-3" higher, plus you don't have as much rubber contacting the road. Less control, decreased stopping ability, much higher chance of roll-over, etc. I didn't get the supercharger to speed around with. I got it for the ease of the vehicle in normal driving and the power and acceleration boost when I want some extra ooomph. Oh, and the only porsche it will beat is the Boxter.

Zach

 

hrmm...i drove my stock (tire and hight wise) truck with s/c averaged about 75-85mph over 300miles of highway up hill downhill...it was at night with not many people on road.....highway was lal mine....the truck did great for lane changes all the way there....had to slow down for the bigger turns though

slow in accel while in the turn and fast out =]

yea going that 105 was pritty crazy....even braking has to be down with ease or else something could happen...gets your heart beating i tell yea that

 

That's pretty bad if you ask me. Like MTL, mine rides great and handles pretty well even up to 90. I've had it up to 108 before and that's when the limiter kicked in. I've only done it once and it wasn't too fun but I usually do around 80 on the highway to and from school every day. I don't have a lift or larger tires, but if I did I doubt I'd do over 75.

 

Just lookin out for ya man.

Plus.....(on the selfish side) need ya around for supecharger install advice.

 

i just got the s/c on mine, but i gots nowhere near 8.5psi. i barely make over 6 psi. do you have the 1st gen s/c, or the new one. i thought i read the first gen provides a little more boost than the new one. also, i was wondering about your engine performance. is it pinging at all with all that extra air, or do you have fuel system upgrades as well?

 

That's what I changed from to the 4Runner hence the feeling of being very disconnected at high speeds. There is definitely nothing wrong with doing 90mph in it, but if something goes wrong with a tire or avoiding something that is it. 90mph = 90 rolls

 

ok, last night i got on the gas pulling a steep grade on a freeway out here. at about 90mph (i know, i know - not safe. i'm still young and stupid), but my boost gauge read just over 8 psi. anyone know why it doen't have that high of an output in the lower gears under full throttle?

 

I have the 2nd gen. S/C, the black one. No fuel mods yet -- soon though. I do have the ISR and deckplate mods done -- maybe that's it? I think when your tires are rotating at 90mph there is more centripetal inertia that keeps them (and then engine) rotating at the same speed. When the limiter came on, the wheels and engine were still spinning at the same speed, only it wasn't allowing as much flow, hence the jump to 12 psi right when the limiter came on. I don't know if that will confuse you more or not. I can't really explain what I'm thinking, plus I don't really know what I'm thinking...

Zach