: Northstar rev limiter



weister42
07-05-12, 03:43 PM
I'm reading up on a bunch of threads about the rev limiter on my 98 Deville vin y N* and I have a few questions... some says the rev limiter is set at 4k in Park or Neutral but that's not the case with me. Some say the rev limiter only works in N, some say it's limited at 6500rpm in P and N.

Now I do remember seeing 6250rpm on my dash in Park when I accidentally sat something on the gas pedal so is my rev limiter at 6500rpm in both Park and Neutral?

Ranger
07-05-12, 03:55 PM
To the best of my knowledge it is set at 4000 RPM in neutral or park. I know mine is.

CadillacLuke24
07-05-12, 04:11 PM
:suspect:

Max power for our LD8s comes at 5600 RPM, or that's what the manual says for my car. I've seen my engine rap to 6250 as well when I wasn't paying attention to my right foot. Scared the crap outta me. Other than that she never clears 5700. I'd imagine that's the shift point.

The FSM says nothing on the topic. My guess would be that you are probably ballpark. My advice is that you DO NOT try and find it, or you'll have your car looking like a Nascar car when their engines go....bottoms of connecting rods trying to spit out the exhaust.

Submariner409
07-05-12, 10:16 PM
Dollars to doughnuts it's a 2000 and later change. My 2002.5 will NOT rev past 4,000 in P or N. Nor will the 2001 SLS I maintain for the guy up the road..........

Always determine which series of engines - to '95, '96/'97, '98/'99, or 2000 and later the advice refers to. They're all different mechanically, electrically, and electronically.

There is no such thing as a "generic Northstar", and we all get into trouble when we forget that.

With your foot stuck through the firewall the shift point is at redline - about 6300 rpm. If it shifts early, your TPS or MAP is sending bum dope to the PCM/ECM. If you're afraid to try and break the gas pedal you're not driving the car to its maximum potential.

weister42
07-05-12, 11:12 PM
Yeah I can rev past 4k in P or N so my guess is the older Northstars don't have that "safety" feature. When I step on the gas pedal all the way down it shifts right at 6000rpm and I don't have any codes. I bounced off the rev limiter once when I was showing off my new exhaust to my friend but I didn't catch the rpm.

I want to know where my rev limiter is set because I might enter the local loud exhaust competition for fun.

CadillacLuke24
07-06-12, 03:05 AM
Well, I gotta commend you on doing it properly :D Good luck. I'd go with 6000 or 6300.

Ranger
07-06-12, 12:56 PM
I thought they all had a rev limiter, but maybe I'm wrong. The limiter is programmed into the PCM.

Submariner409
07-06-12, 01:50 PM
Rev limiter for the engine, speed limiter for the max tire rating OEM.

weister42
07-08-12, 12:05 PM
Rev limiter for the engine, speed limiter for the max tire rating OEM.


Yep and my car is limited to 112mph, which sucks because it gets to that speed fairly quick. Raced against a Dodge hemi truck, a brand new Subaru BRZ and a Ford-F350 turbodiesel that's pushing 600+ lbs. of torque and I gave all of them a run for the money (none of them pulled any significant car lengths on me).


Sometimes bouncing off the rev limiter makes your car sounds like it has an anti-lag turbo setup, and I'd like to know if I can mimic that at the show without breaking something. Aren't the N* actually good to about 7000rpm so you can't break it as long as the rev limiter is working?

Submariner409
07-08-12, 12:33 PM
I believe you can change the vehicle speed limiter set into the PCM - talk to either pcmcalibrators (AJXTCMAN) or Wester's Garage. The engine rev limiter is a different story, but I do know that the early Northstar prototypes (Lotus) went to over 8,000. Kicker is, with your flat tappet cam followers, twisting that engine too fast too much would get expensive in a hurry.

If you removed the speed limiter and put Z tires on the car you could nurse it to top speed (power and drag max speed) and never come close to 6,300 in 4th - the cars will do over 130 in 3rd. Of course, never try any sort of track speed runs unless the car is in perfect mechanical condition.

CF does not condone or support any form of street racing. I assume that your runs against the trucks were done at a sanctioned drag strip - the C5 fest ???

CadillacLuke24
07-09-12, 04:11 AM
Hahaha I bet they weren't expecting that from a Grandma rider! :lol: I love the surprise people get from these Cadillacs who aren't expecting much.

You can tune it and get some things removed, but if you really want a hot rod go V1 shopping. They're under 20K nowadays for certain ones.

weister42
07-11-12, 07:32 PM
I believe you can change the vehicle speed limiter set into the PCM - talk to either pcmcalibrators (AJXTCMAN) or Wester's Garage. The engine rev limiter is a different story, but I do know that the early Northstar prototypes (Lotus) went to over 8,000. Kicker is, with your flat tappet cam followers, twisting that engine too fast too much would get expensive in a hurry.

If you removed the speed limiter and put Z tires on the car you could nurse it to top speed (power and drag max speed) and never come close to 6,300 in 4th - the cars will do over 130 in 3rd. Of course, never try any sort of track speed runs unless the car is in perfect mechanical condition.

CF does not condone or support any form of street racing. I assume that your runs against the trucks were done at a sanctioned drag strip - the C5 fest ???


Yes. Just getting friends to help me clean the carbon with those WOTs :) But yes, I am content with the speed of my 14 year-old car with almost 200k miles, pretty amazing if you ask me.


I like the Northstar V8 with its 32 valves and the noise it makes and I will continue to represent!

CadillacLuke24
07-12-12, 02:56 AM
Damn straight. Many times, like tonight, I'll shut off the garbage they call music these days, roll down the window, and listen to the Northstar Symphony, No. 8 :D

maeng9981
07-14-12, 01:07 PM
The 93-99 doesn't seem to have a park/neutral rev limiter, or it's set high somewhere around 6000-6500 rpm. The 2000 and above will not let you rev higher than 4,000 rpm in park/neutral. Any Northstar will allow you to get up to 6,000 rpm (Y) / 6,500 rpm (9) in drive.