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Normal Idle RPM...

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Old 01-05-2012, 06:08 PM
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Default Normal Idle RPM...

I feel my Idle is a lil high.
Want to compare with some of you guys to see if its just the cam or thats where it supouse to be.

When warmed up, my ride Idles at around 9 hundred Sometimes close to 1k Rpm.
When im driving, It keeps pushing foward even on uphill streets. At high speeds, i let go of the gas pedal and it maintains speed for a while before it slows down.
I know my ride will never be the same as stock feel, but do you guys n gals think my rpm needs to be lowered a bit?...
Mods in SIG,

All Input Welcome!!!
Old 01-05-2012, 06:20 PM
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Your idle rpm will be determined by whatever desired speed that your tuner has set. If the engine is not maintaining that preset idle rpm, then it is because some outside influence is making it impossibile. The IAC motor should be able to compensate for load changes and normal fluctuations that would cause an increase or decrease in demand of air flow to maintain a steady idle. If you have a vacuum leak or other issue that is beyond the realm of normal, then the IAC may not be able to fully compenstate, and thus you are left with an unstable idle.

The "cruise control" effect that you have described is something that's certainly a common issue with cammed OBDII cars. Back when there was no tuning, and all we could do to get a cammed car to idle was drill bigger TB plate holes or crack the plate open further, this cruise control effect was the norm. But today, there are several tables that can be adjusted during the tune to deal with this, and the best tuners will be able to restore near-stock idle stability with the milder cams such as yours. If the tuner didn't take the time to really sort this stuff out, then the result will be poor idle stability, surging, cruise control effect, and possibily difficult warm restarts.

IMO, your cam should not really need to idle at 900-1000rpm in gear with good tuning. I had a 221° cam idling just fine in my automatic car at 800rpm in gear with only minimal changes to timing/fueling and VE tables. But don't trust your stock tach either, your idle speed may be higher or lower in reality, and the only way to know for sure is with a scanner.

Overall, that's a pretty mild cam and it shouldn't be causing such significant idle hang/cruise control effect IF it's been tuned properly and IF you don't have any vacuum leaks or other hard issues present that are effecting idle stability.
Old 01-06-2012, 10:16 AM
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When I had a big cam in my old car my car would idle at 850rpm's (verified by tuning software) however my tachometer showed around 1000-1100. Just something to think about other than what RPM said. I had an M6 and a 231/234 .640/.590 112 LSA ca,
Old 01-06-2012, 03:11 PM
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My tach reads 1000-1100 but when you look at it on HP Tuners it is really idling 9-950. Point is the tachs are commonly a little off on these cars.
Old 01-06-2012, 03:36 PM
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Mine idles around 950 but I wanted a little smoother idle. Some like the idle choppier. The RPMs are sometimes slow to drop when I put in the clutch but but does not "run on". Like other said, it's probably a tuning thing.
Old 01-07-2012, 09:27 AM
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Thanks for your input Guys...

If i take it back to the tunner and get the rpm's down from idle, it shouldnt affect the HP or Stall on me right?

It just seems like I have a ride in need of ritalin...
Old 01-07-2012, 10:58 AM
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Originally Posted by LASTOFTHEBREED02T/A
Thanks for your input Guys...

If i take it back to the tunner and get the rpm's down from idle, it shouldnt affect the HP or Stall on me right?

It just seems like I have a ride in need of ritalin...
If you have them drop the idle too low, you might have some surging issues. There may be some other tables that need some adjustment besides just the desired idle speed. Have your tuner take the car on the road and make sure he sees the condition you're describing.

But none of these changes would effect WOT horsepower.
Old 01-07-2012, 11:02 AM
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Before my cam i jad it at 300 thats what the tac said and it would surge like you had a big cam.
Old 01-07-2012, 12:15 PM
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Originally Posted by RPM WS6
If you have them drop the idle too low, you might have some surging issues. There may be some other tables that need some adjustment besides just the desired idle speed. Have your tuner take the car on the road and make sure he sees the condition you're describing.

But none of these changes would effect WOT horsepower.
I was hoping it had nothing to do with WOT HP...
I just have to remember to tell them about looking at all the tables a lil closer, and drive it for a while.



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