Hello/Beat that dead horse again! clarification

CSH-HQ nacelp at jvlnet.com
Sat Oct 30 15:02:39 GMT 1999


Well, that explains a bunch, we're not mind readers here, and can only deal 
with what you write.  When you leave 1/2 the details out, don't be surprised 
about the responses.
  Next, without reading the prom you already have, anything is jut quessing.
With no diacom runs, it's even more difficult.
  I'd bet if you hook up a diacom you'll see the MAF is pegged at less than 
3,000 RPM.  Which means the top end of the calibrations are only a quess.
  The gn ecm is for a v-6 Sequential, and no help here.
  How much boost are you running?.
  If you went to a MAP system then you no longer have the MAF as your 
limiting factor, or latr PCM with one of the after market high CFM MAFs.
  Personnally, the only 2 bar MAP application in the gm world is the syclone.
/sunbird.  Which means going to a 3 plug ecm from your 2 plug.
  There are no easy answers to what you've generated.
Are you using a VSS?.
  Is the chip for a manual tranny in a manual application, or auto in auto?.
P/N switch hooked up?
  What is and isn't correct.  Or is this an all oem wiring/application?.
All of the above matters.
Grumpy

>OK guys, let me reword the original message and clear up a few points along
>the way.
>
>I designed and built and engine. I designed the cam. ACCORDING tot he CAM
>GRINDER and HIS computer, that cam is good for 600-650 HP, with all other
>factors taken into consideration such as heads and the rest of the
>modifications done. *I* limited the engine with 30# injectors, so if there
>was any possibility of the stock computer, with a chip in it that has
>already been modified for the supercharger.  I'm a mechanic, not an
>electronics engineer. Please, whenever possible, put your replies into
>laymens terms, and that would help a bunch!  :o) Thanks.
>Now, back to my original problem. When the engine hits 5400 rpms, it just
>stops. I was told on another list that the computer limits the rpm's at 5400
>on a stock L-98 enine in 1989. BEFORE the modifications, with only the
>supercharger, it did the same thing. I really need to spin this engine up to
>at least 6000....so, does the computer limit the rpm's at 5400 or is
>something else doing it?  It did it with the old stock injectors, and i
>would have thought that the engine would lean out at a higher rpm with the
>new 30# injectors.
>Next problem is the idle. It is hunting between 500-700 rpms. The cam is on
>the radical side, along with custom made full roller 1.6:1 rockers. I HAVE
>to raise the idle up to about 800-850 rpms, as it dies right now when coming
>to a stop about 1/2 the time, especially when the engine has been running at
>WOT, and then letting off the gas, it dies almost immedatly.
>I am sure that there are other factors to take into consideration that I may
>not be aware of as of yet. The engine is also equiped with water/alcohol
>injection, just ahead of the throttle body to help eliminate detonation, and
>that combined with the lowered compression ratio has done a GREAT job, and
>no knock or detonation is apparent, even under full boost conditions, so I
>don't *think* that the advance curves need to be played with any more than
>they may have already been altered by the custom chip that is already in
>place.
>
>Someone on the list suggested swapping out the computer with one from a
>turbo GM car. Good idea, but, just HOW would I go about this, and is it
>compatable with an 89 Corvette onboard systems already in place?
>
>Inquiring minds want to know :o)
>
>Thanks to everyon that has been involved in this thread to this point,
>pleasae be patient and I will get up to speed.   TIA!
>-Barrett
>SCAR Corvette & Performance
>1010 W. Hwy 131, Clarksville, IN  47129
>(812) 941-0839
>bluvette at scarcorvette.com
>www.scarcorvette.com
>
>




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