True Rev Limit @ 6450?

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chrismo240sx
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i just got off the phone with Jim Wolf Tech and was asking them about the 275 deg cam for the 240 w/ the ka24de....anyways as everyone knows(or should) the s13 redline is 6900 and the s14 is 6500 from the factory with rev limiters @ 7200 and 6750 respectively.

However, Jim Wolf is saying that the true rev limiter on both is actually 6450 rpms no matter s13 or s14...so our tachs are misreading the true rpms. So theyre saying that when i see 7200 in my s13(very rarely) its realy only 6450....is this true? Anyone else know anything further about this or if it is indeed tru or not?Ive been told that most tachs are off by a few hundred maybe 2-300 but not my almost a full 1000.Anyways feel free to post and expands thoughts/views on this topic and sorry for making it such a long read!


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Dattebayo
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Why does it matter? It's not like the KA makes any power up there anyway...

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xckid
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apparently rev limiter aint sheet when your down shifting. I once down shifted to too small of a gear on mistake to avoid a accident, And I just saw my Rpm go to 8 k......i was sure my motor was a gonner...nope 10k miles later shes still running strong lol. God im glad

chrismo240sx
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Dattebayo wrote:Why does it matter? It's not like the KA makes any power up there anyway...
well not on a stock motor but with this 275 deg cam and header it will be making power more towards the stock redline, but i was just curious and wondering why they would be so off like that......and damn dude, 8k on the Ka? haha not good

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CRyan
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had my car on the consult II today at work.

The Consult read it idling at 675-750. The tach looks like it was in that area roughly. The Conult doesn't lie.

And apparently - neither is my tach lol. But I dunno if it changes in higher RPM's or not. . .I wouldn't think so. . .

chrismo240sx
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true but like i said before, ive heard of tachs reading slightly higher to keep you from blowing the motor or constant over reving into redline but not this far off....maybe the tach is right on in lower rpms but goes further off the higher up you rev?

Arrow
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Also you should know that since the tach is analog it will read off by some exponential rate the higher the gauge is to its max. So basically your tach will read correct (or so close you can't tell) at idle, but the higher it gets the further it will be off. And that is with ANY analog gauge so that includes speedometers as well... Now I'm not going to say how far they are off near the end of their limit, but they are off.

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CRyan
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Arrow wrote:Also you should know that since the tach is analog it will read off by some exponential rate the higher the gauge is to its max. So basically your tach will read correct (or so close you can't tell) at idle, but the higher it gets the further it will be off. And that is with ANY analog gauge so that includes speedometers as well... Now I'm not going to say how far they are off near the end of their limit, but they are off.
Well put! I had just read about the analog gauges and what not. Beat me to it dangit

But yeah.

What he said.

chrismo240sx
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wow thanks for the info man...makes sense to bc when im cruising at 80, well my speedo is reading anyways....i know for a fact im not really doing 80 bc 1st off...it doesnt feel like 80 and 2nd ive driven besides friends and my brother and even see other cars speedos sometimes and they all read and say 76 mph when mine reads 80....so yea i guess it does read more and more inaccurate the higher/faster you go.

Cone Junky
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xckid wrote:apparently rev limiter aint sheet when your down shifting. I once down shifted to too small of a gear on mistake to avoid a accident, And I just saw my Rpm go to 8 k......i was sure my motor was a gonner...nope 10k miles later shes still running strong lol. God im glad
Well the rev limiter only works to cut off fuel/spark at a certain RPM. With an incorrect downshift, there is a mechanical link that can't be "cutoff". So it can't keep you from doing that

pflicht
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I've pegged my tach several times... +8K RPMs not good, but it still runs!

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SketchyRollin564
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Dattebayo wrote:Why does it matter? It's not like the KA makes any power up there anyway...
ever heard of KA-T? its pretty sick
xckid wrote:apparently rev limiter aint sheet when your down shifting. I once down shifted to too small of a gear on mistake to avoid a accident, And I just saw my Rpm go to 8 k......i was sure my motor was a gonner...nope 10k miles later shes still running strong lol. God im glad
lol money shift

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ADF932
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I have a quick question. What do you remove to get rid of the speed limter?

pflicht
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ADF932 wrote:I have a quick question. What do you remove to get rid of the speed limter?
Search!

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xckid
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ADF932 wrote:I have a quick question. What do you remove to get rid of the speed limter?
lets see how quick this thread can last now

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giodachamp
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SketchyRollin564 wrote:
ever heard of KA-T? its pretty sick
he's probably talking about the stock KA

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ThuG LyFe
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y must ppl always be a holes or smartasses when people ask obvious questions?

to remove a rev limiter/speed governer you will need a automatic ECU. thats why some ppl that get a auto-> manual conversion leave the ecu auto to get rid of the limiter/governer. about the fuel cut off tho i have no idea i never reved past 5k i think and only a handful times.

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anti_flag_army
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wahrheitoderpflicht wrote:I've pegged my tach several times... +8K RPMs not good, but it still runs!
Psh 8k IS my redline and from what i hear, the actual "redline" the engine is capible of is much higher (just going off what i heard)

chrismo240sx
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"y must ppl always be a holes or smartasses when people ask obvious questions?"

well first off because im somewhat new here and know for a fact ive seen this topic atleast 10 different times....2nd, if u use the search button, the answer is there waiting for you if u would just do some easy research and 3rd because its thread jacking and has nothing to do with the title of this post

got chub
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when i bought my car it had the black base model gauges and then i swapped it out to the white SE gauges. well any way the black gauges when my RPM were at 3k on the highway i was going 70MPH with the SE gauges at 3k on the highway I'm doing 66MPH. i checked both speeds with my the GPS on the navigation so the speeds are accurate.

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ADF932
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pflicht wrote: Search!
I will next time. Thanks for your advice.
Modified by ADF932 at 2:37 PM 4/6/2008

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ADF932
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I can relate to the tach being off. I noticed that the speedometer on my car is also off. The other day i was driving down a road that has those speed readers. I was going 30MPH and the speed reader said i was going 40MPH. Unless the reader is faulty.

chrismo240sx
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i dont know about being that far off at low speeds such as that....the faster u go the further off the speedo and tach get...i was driving yesterday with my brothers navigation and shows avg speed and top speedi hit my speed limiter in 5th a few times where my speedo read way past 110mph but the navigation thing only read a max speed of 109mph.

i was kinda pissed bc i was always told the cut off is around 118 somewhere but i guess not haha


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