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Old 03-05-07, 11:58 PM   #1
Blk97SC300
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Default How to increase the stock rev limiter?

Hey guys, I have a 97 SC300- I'll be swapping it to a 5spd this weekend. Within a month, I will install a T67 turbo, along with a thicker head gasket (OEM supra TT, lowering compression to 9.0:1), and tune with a MAP ECU. The stock rev limiter is pretty low (6,250 or 6,500.. not exactly sure). Some extra room to rev in each gear would be kinda nice to have...

Is there any way to raise the limiter? I have a manual tranny ECU by the way- not sure if it makes a difference though. Is there a way we could possibly rev to 7,000? Maybe even 7,500? I tried searching, but nothing came up. Any thoughts or suggestions would be great, thanks in advance.

-Allen
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Old 03-06-07, 02:07 AM   #2
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the emange ultimate claims that it can alter rev limit (there might be other piggybacks, but i'm not sure) although i don't now if anyone has done on an sc300 and see if that function actually works, otherwise it will take a stand alone.
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Old 03-06-07, 10:12 AM   #3
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Has anyone in here "overclocked" the ECU? I had someone overclock the ECU on my 3000GT VR4 by 10%- raisining the limiter to 8,000 rpm. All that needed to be swapped was a single little crystal on the ECU's board.

-Allen
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Old 03-06-07, 10:29 AM   #4
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I do believe the Ausse's have addressed this one before...

http://planetsoarer.com/ecu/ecu.htm
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Old 03-06-07, 10:29 AM   #5
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The Rev limiter is set for reason. Changing it without changing the fuel map and other misc parts harms the car and makes it starv for fuel cause it is going past the fuel cutoff! My suggestion is look for a ECU reflash they usually add higher revs and change the fuel map and other misc parts. Other then that if you want to change it you need to get it dynoed so they can reflash the ecu and the fuel map so it compinsates for the add revs!

Hope this helps good luck! Also post detailed pics of the swap with instructions. As I mentiond to you that I wanted to do the swap this summer and it would be nice to get some references.
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Old 03-06-07, 07:49 PM   #6
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you wont need the extra rev you'll have a turbo i dont thin you will get very much lag the tt head gasket wont lower your compression to 9:1 boost first then worry about if you need more. baby steps dont blow your motor
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Old 03-06-07, 08:17 PM   #7
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changing your cam shaft will it increase revs or lower rev limit?
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Old 03-06-07, 09:30 PM   #8
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im curious too. because im gonna be turboing my car any time, and running a t70 with fuel and all the jazz. but im gonna be running map-ecu2 and increaseing reves to atleast 7k would be nice
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Old 03-06-07, 11:56 PM   #9
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Quote:
Originally Posted by Sc dRifta View Post
you wont need the extra rev you'll have a turbo i dont thin you will get very much lag the tt head gasket wont lower your compression to 9:1 boost first then worry about if you need more. baby steps dont blow your motor
I ordered a boostlogic 2.5mm head gasket, so my compression will be 8.5:1.

I believe the rev limit on a manual sc300 is 6800rpm- so I think that should be fine. I thought it was the same as the auto rev limiter. Could anyone verify this?

-Allen
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Old 03-07-07, 01:21 AM   #10
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Revving too high on a stock 2jz-ge head will float your valves = destruction.
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Old 03-07-07, 02:03 AM   #11
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What is too high?

Ian
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Old 03-07-07, 07:06 AM   #12
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Quote:
Originally Posted by dejacky View Post
Revving too high on a stock 2jz-ge head will float your valves = destruction.
word if you want to rev high get a 1j and call it a day
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Old 03-07-07, 08:12 PM   #13
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Quote:
Originally Posted by Blk97SC300 View Post
...the rev limit on a manual sc300 is 6800rpm... Could anyone verify this?
That's where mine kicks in. The T61 is just pouring on power straight up to cutoff were my peak h.p. numbers hit, so there's more if it went to 7000.

Now running a Supra TT obd1 ecu, though the SC300 ecu was same rpm cutoff.
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Old 03-07-07, 10:09 PM   #14
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6800 for you guys?. mine is like 6200
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Old 03-08-07, 12:17 AM   #15
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Yeah 6800, tested at the track tonight. Anyone know what the safe rev limit of the stock head is?

Thanks!

Ian
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Old 03-08-07, 12:17 AM
 
 
 
 
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2009, 2jzgte, 300, 350, cutoff, increase, lexus, limit, limiter, raising, rev, rx, sc300, sc400, speed, stock

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