Re: Poll: Who has ever hit the rev limiter?
 

As a matter of fact she is going on the dyno tomarrow after work so we will see what happens

Re: Poll: Who has ever hit the rev limiter?
 

Same here. Mine pulls beyond 7k. I've driven many others Z's that don't run as good as mine. I always thought that there was just something wrong with theirs. Maybe its the other way around. Maybe somethings been done to give it more pep besides what I've done to it. I guess I'll never know. Not knowing doesn't hurt my feelings one bit. Lol!

Re: Poll: Who has ever hit the rev limiter?
 

8k? Yeah, maybe. It would take cams and some porting and exhaust, etc to pull to 8k. With 315x35x17s at 7200 rpm in third, 3.45 rear gear will get you to 120 ish mph. If you're north of 132 mph + in 3rd gear, I would agree you're rubbing shoulders with 8k. Otherwise, I suspect the tach is off a bit.

I knew my tach was reading high (common problem) but not 20% high! Marc mentioned it and I confirmed with my scanner too - yep - 20%. The tach would run off the scale and then some before the limiter would engage!

So, screw the tach. I did calibrate it, and now it tracks pretty well. But, the shift light is soooo much better for best/consistent shift performance and avoiding testing the limiter, methinks;)

P.

Re: Poll: Who has ever hit the rev limiter?
 

Not me,most this cars seen from me is a touch under 6 grand,if I break it cant afford to fix it.

Re: Poll: Who has ever hit the rev limiter?
 

Under 6K???

Dat LT5 ain't no LT1! Let da big dog loose! :dancing Dave Mclellan says the LT5 loves to rev to 7k "...and it will thank you for it!"

:cheers:

P.

Re: Poll: Who has ever hit the rev limiter?
 

HAVE TO AGREE

Ain't nuthin better than to let the 32 DOHC's and 16 FI's do their thing and that is to REV and to REV HIGH very HIGH!!!

She was designed and born to run just like a

"Cheetah" achieves by far the fastest land speed of any living animal—between 112 and 120 km/h (70 and 75 mph) in short bursts covering distances up to 500 m (1,600 ft), and has the ability to accelerate from 0 to over 100 km/h (62 mph) in three seconds.

Re: Poll: Who has ever hit the rev limiter?
 

Saw where prey animals will freeze to avoid being noticed by a Cheatah preditor they can't out run.

Saw something similar a while ago when a "C4" linend up against some prey C5/6s. The prey animals in the stands were chatting it up and loudly scoffing. They didn't realize it was Pete's predator Z about to prey on the one of theirs...

The next time that Z came to the line, the prey animals in the stands went quiet! LOL!

P.

Re: Poll: Who has ever hit the rev limiter?
 

Re: Poll: Who has ever hit the rev limiter?
 

Yep. I bought this car to have fun. I don't plan on hitting again but hey, **** happens. I didn't mean to hit it the first time.

Geoff Jeal told me that during the LT5 Calibration Certification, the LT5 was run for a continous period with an RPM cycle of 5500 to 7100 and back again. Not one component failed and not one fastener came loose. This was the certification. Seem like the duration was 200 hrs?

Re: Poll: Who has ever hit the rev limiter?
 

Yup. Hit it by accident. Hit the throttle in second and spun the tires. Surprise, hit the limiter! Thought I blew the motor! Then I realized it was the limiter. Nice insurance!

Re: Poll: Who has ever hit the rev limiter?
 

The question should be who has not hit their rev limiter. If the answer is they have not they should be forced to release their car to a car ( ZR-1) enthusiast and buy a Prius. That is the most ridiculous question I have ever read. I really hope there is no one that would take pride in admitting that. If they do they probably live an alternative lifestyle.

Re: Poll: Who has ever hit the rev limiter?
 

Well, I'm pleased to say, I don't think the po, nor myself run this car bouncing off the rev limiter. I've seen the ricers run their cars that way and they all smoke. I would rather throw my money at improvements, not repairs.

Re: Poll: Who has ever hit the rev limiter?
 

I have an L98 and an LT1 in addition to the "Black Momba" and I rarely hit the rev limiter on those cars. I typically shift based on the power curve and after owning and driving these cars for years you just learn where the shift points are. However, that is not the case with my Black Momba.

I've hit the rev limiter more times in that car then I have combined in the other two. Some of this is based on me still getting use to the car but damn, this car pulls all the way to the set limit.

Re: Poll: Who has ever hit the rev limiter?
 

WHAT!!
You sold the 92???

:(

Re: Poll: Who has ever hit the rev limiter?
 

The CR1 went to the new owner on Monday. Two down and one more to go. You need a twin turbo for your collection. Come get it. :cheers:

Re: Poll: Who has ever hit the rev limiter?
 

...and know what a "NO-NO" is (and use one!) - definitely are WAXERS!:sign10:

Re: Poll: Who has ever hit the rev limiter?
 

Hey Big John, I'll drive ya' out there to pick it up.

Re: Poll: Who has ever hit the rev limiter?
 

My sentiments exactly :thumbsup:

I am shocked...:confused:...SHOCKED at seeing the poll results.
Almost HALF of the respondents confess to never treading the furthest regions of the LT5's rev capacity. :redface:
What a disappointment. You 'oughta be ashamed :thumbsdo:
Well, just keep changing that oil kids, keep it nice, polish that paint, and put some more shiny juice on them tires. 'Cause some day a real ZR-1 enthusiast might own that car. :p

(If the above comments offend thee, I am deeply sorry and wish to blame it on the three cups of coffee I've ingested so far today :cheers:)

Re: Poll: Who has ever hit the rev limiter?
 

OK, I'll confess. I've never hit the limiter but not for lack of trying - it's for not knowing where it is! Anyone know what a typical DRM chip sets the limiter at?

I'd have to dig to find the dyno sheet from early in our ZR-1 adventure but I seem to recall power peaking maybe middle 6k's or so and I don't think we went to the limiter on those three runs.

I have to make the 1-2 shift by where I am on the course, not by rpm. And although it sometimes feels like it I never quite reach the top of 2nd gear (I need to go to the 3.54 rear, most I can do within class rules). For this car, the street is just for transport between events - and soon that will be by trailer.

Cheers,
- Jeff

Re: Poll: Who has ever hit the rev limiter?
 

Never...LOL

CatBack Flomasters - YouTube

Re: Poll: Who has ever hit the rev limiter?
 

Where's the option for "Not yet?"

Re: Poll: Who has ever hit the rev limiter?
 

People are very afraid of damaging an engine, GM set that limiter way below the point of rev related damage.

I remember the poster of a ZR-1 on my buddies wall, fuel shutoff=7200rpm. Such a magical number esp. for a stock GM engine with 80's technology.

Re: Poll: Who has ever hit the rev limiter?
 

With the "500" package installed, it was still pulling hard when I would hit the 7200 limiter. In fact, I'd hit the limiter in 3rd gear just short of the 1/4 mile finish line. Marc reset it to 7600, and once in the "water box" at the track, I tickled 7600 briefly.

Now I depend on a shift light, which does NOT lag. I played with the trigger point until I found that spot where my 1/4 mile passes were optimized; 7100, if memory serves. (By the time I react, I'm at 7200-7300ish in 1st, around 72xx in second and the light comes on in 3rd very close to the finish line - on a good day.)

In the book "HEART OF THE BEAST" the certification was to cycle between max rpm every so many minutes (hours) and max torque. This they did for 200 hours; OR 8.33 DAYS! The test crew reported back to Dave McLellan after measuring it for wear, and told him it was good to go for another round. I don't think you're gonna hurt it if you bump the limiter, and certainly not for a run at 7000 rpm.

If the motor is stock, then (as I recall) 6800 shift may be about right. But, after the full porting, headers, free flowing exhaust and cam phasing, 7200 is too little - least here in FBI land.:dancing

Re: Poll: Who has ever hit the rev limiter?
 

I hit it today. At around 50 degree cool air, that Turq car is absolutely brutal with the B&B exhaust and 4:10 gears. Can't wait to do a stroker!

Re: Poll: Who has ever hit the rev limiter?
 

Temps dropped to about 40 degrees here this morning. I didn't hit the rev limiter but I did hit the tire limiter--Couldn't get any traction in either first or second gears. Even third was a bit iffy. Still fun though until the first snow flies. --Bob

Re: Poll: Who has ever hit the rev limiter?
 

just saw this old post,
90 is the one only that has the shift light for performance, the rest have it for fuel economy

Re: Poll: Who has ever hit the rev limiter?
 

I just saw this....

Not true, my 91 lights up for performance, and mine is all stock. I don't remember the actual rpm it lights up, but some where around 6400 I think.

Re: Poll: Who has ever hit the rev limiter?
 

i'm trying to recall my conversation with marc but i'm too many beers in to do so accurately, I thought he said it was 90 only. oh well I've been wrong before

Re: Poll: Who has ever hit the rev limiter?
 

I hit it once in an '02 1-Ton Express Van that I bought new.

Kicks in @ 100mph. Felt scary too - heavy torqueing 5.7 has inertial forces at 100 that shouldn't change like that.

I had 265's on the corners, instead of 245's, so it was about 107 - 108 :p

Lickety-Split Courier & Delivery!

https://lh5.googleusercontent.com/wP...w813-h426-p-no

I had it subsidiary of my primary C&D............

Re: Poll: Who has ever hit the rev limiter?
 

Around 6400 ya think? Hmmmm....

Pete and I were discussing the topic of where to shift for performance (on a stock ZR-1) with Jim (Jingles) Inglals (sp?). (Jim was the Corvette engineer that established - among other things - the drag strip numbers for the then new ZR-1) As I recall he recommended POWER shifting the Z at around 6300-6400 rpm (no throttle let-up between gears).

I think Pete and I agreed that neither of us is going to do any POWER SHIFTING as long as its on our dime if something breaks![-X But, to your comment regarding the UPSHIFT light coming on at 6400 for performance(?)...makes me wonder if it isn't more than just a "koinkeedink"

But, here's the thing: If Jim power shifts at around 6400, according to the tach, the actual rpm might well be at least a few hundred rpm higher than 6400, especially in the lower gears.

Just muddying the waters a bit...:cheers:

Re: Poll: Who has ever hit the rev limiter?
 

the question was,, can it damage your car?? well just yesterday I met up with a nice guy in my neighborhood with a 1991 z, he seems like a very handy person with lots of equipment in his garage, welders, press etc.. he had just powder coated and ported his top end and his cam covers.... but on the side of his garage on a crate stood a wrapped up lt5. he just bought that engine used because he over-reved his engine and damaged it. he turned it on and it make some bad noises internally. he thought it was maybe damaged lifters so he replaced some of them. he decided to replace the whole engine so he bought a long block. he was driving around while his tach was not working and over-reved it and lost his motor. I know when I have hit the limiter on my c5 it just drops cylinders and stumbles. maybe the lt5 will do the same but again we are doing many more rpms than a c5 would be doing so the damage is more iminent. I would say not a good idea bumping that limiter too many times. by the way, this friends zr1 had 130k miles on it and still was running as strong as a bull.

ed ramos #3028

Re: Poll: Who has ever hit the rev limiter?
 

Yeah, you may be right on that. I don't watch the tach very closely anymore except for the hole shot, where I bring it to 4000 off the line.

I just grab the next gear when the shift light pops, and in my peripheral, it looks like the needle is around that 6400 mark. The car is dead on consistent shifting with the light, though.

To the power shifting comment:

I power shifted it once on the street, and without a prepped surface, it blows the tires off on the 1-2 shift. That shifter has such a long throw though, that you really have to train that clutch leg to stay in long enough to complete the shift. I haven't, nor am I interested, in power shifting that 3-4 shift.

No worries on the muddy water...it makes things interesting. :cheers:

Re: Poll: Who has ever hit the rev limiter?
 

Yeah, on a traditional pushrod motor, hitting the limiter can cause valve float. When that happens, the valves could contact the piston **BANG**.

In our LT5's, the movable valve train weight should be less, since there's no pushrod, so I would think the force would need to be much higher to get the valves to float. That sudden stop in accelerating RPM's still creates forces within the engine that attempt a valve float.

That's why aftermarket rev limiters try to soften that stop, like MSD's soft touch rev limit.

Re: Poll: Who has ever hit the rev limiter?
 

I've bumped it a time or two.......best I can tell the Lingenfelter is set at 8200.
:eek:

Re: Poll: Who has ever hit the rev limiter?
 

Does anybody with a MY 1994/1995 have a OEM "Shift Light"? I have an aftermarket,
but never noticed or saw one that would have come with the car.

Re: Poll: Who has ever hit the rev limiter?
 

Hi Ed--
We have a good FBI friend named Al who ran into a little problem at last year's half mile races. Here is a video of what happened to his motor due to a little over revving: http://www.youtube.com/watch?v=bgQiABT05tM --Bob

Re: Poll: Who has ever hit the rev limiter?
 

The limiter is there to prevent over-reving the motor, and in and of itself isn't going to cause any catastrophic issues. After completing the "FBI 500+" package, including the Fidanza FW and before installing a shift light (on my 90) I often bumped the limiter. It is nothing more severe than miss firing/sputtering or missing (read: pretty soft, but no drivetrain shock).

Before I had my rev limiter bumped to 7600 and a shift light installed, I'd hit it quite often - Here is an example of how soft the limiter is:

This is Pete's Green Monster. Notice the little misfire on his second burnout at about 1:05.

http://www.youtube.com/watch?v=SFNFOhGGlR4

Nothing to worry about...BTDT many times, w/o issues - NO crashes of gears or anything like that. Very soft.

P.

Re: Poll: Who has ever hit the rev limiter?
 

I understand it is to prevent over-reving of the motor but there are only so many times a motor is going to let you bust its gut until it busts yours. they are definitely great engines and durable but they are not indestructible. My friends lt5 had 130k miles until it blew up. he bought the car with 120k miles. those are miles that could have been done a 1/4 mile at a time. I understand bumping the limiter during a grudge match or something. i dont understand just bumping it every time you go for a drive.

I dont like to be hard on my equipment and that is why I have never had catastrophic failures even in race engines. I use it and get what I need out of it at the time and leave it. I wont just beat on it for kicks. everybody has different driving habits and of course if the owner wants to rev it every time then its ok. I just think engines that are thrashed continually will one day bite you in the rump. that guys zr1 in the video is a monster. 11.30 at 129 mph and no power adder. Great car and great power.

ed ramos #3028

Re: Poll: Who has ever hit the rev limiter?
 

Bumped it about 10x last week when I took it out. have to get a feel for where it is on the tach because they aren't exactly accurate. Pretty much figured it out now. I have no fear with this motor at all. if it blows up oh well stroker time :-D

Re: Poll: Who has ever hit the rev limiter?
 

Tach calibration is a relatively easy DIY fix for anyone familiar with basic electricity; just soldering in a resistor in place of the deteriorated, printed one.

I believe Dynomite (our club's Archive guru) has the procedure captured in his archive. Check there first. Or, I have a copy of the article I wrote on it...somewhere around here if you need me to dig it up for ya!:dancing

http://i185.photobucket.com/albums/x...ut4and10-2.jpg

Course too, with any analog meter (tach in this case) there is a certain % of lag which increases with changing (rpm) rate; naturally there's more in first gear especially. SO...a shift light is recommended. And, in the archives too is procedures for installing one. (I installed a Raptor light which is small enough to be hidden behind one of the vent grills. All seven LEDs wink on and off in sequence when the ignition is first turned on - as a test mode.)

http://i185.photobucket.com/albums/x...aptorlight.jpg

In the book, "Heart of the Beast" there was a problem discovered when a single chain was used. But, the cure was the double chain that the LT5s have now. In the book, it describes how Lotus engineers tested the motor by alternating the engine between peak torque and 7000 rpm for a little more than a week w/o issues. So, I don't think occasionally hitting the limiter at approx 7200 is "pushing it" at all, long as it hasn't been run out of oil or the like. It ain't no pushrod motor!:cheers: