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Blipping the throttle

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Old Feb 16, 2006 | 07:57 PM
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Question Blipping the throttle

Looking to make the engine revs come down a little sooner when blipping the throttle a little in neutral. Nothing extreme, just seems these engines are slow at returning back to idle compared to an sbc or late model Mustang. I've fixed the hanging idle/cruise effect in the past using hptuners, so that's not the issue. What do I adjust? Throttle cracker, follower, decay, delay? Thanks for any info.
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Old Feb 17, 2006 | 10:48 AM
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Can somebody throw a dog a bone?
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Old Feb 18, 2006 | 02:12 PM
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Zero out your throttle follower delay table and reduce or zero out your throttle follower airflow table.
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Old Feb 18, 2006 | 03:24 PM
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Would increasing the throttle follower decay tables have the same effect? My throttle follower delay table is zeroed out already.
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Old Feb 18, 2006 | 04:10 PM
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its not the delay that effects it its decay
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Old Feb 18, 2006 | 05:51 PM
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Thanks for the info. I'll experiement with those settings then.
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Old Feb 19, 2006 | 09:28 AM
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You may want to try zeroing out the whole throttle follower airflow table and then add back to it if it's too much difference. If the airflow is zero then the decay doesn't matter.

Last edited by P Mack; Feb 19, 2006 at 09:33 AM.
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Old Feb 21, 2006 | 03:16 PM
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I don't know if it applies to this situation, but would the DFCO settings be useful?
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Old Feb 21, 2006 | 08:31 PM
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I made the changes to the Throttle Cracker Airflow table like you guys suggested and it made a nice difference how fast the throttle returns to idle. Not quite SBC style yet, but real close. I actually copied your table WS6FirebirdTA00 from this thread
https://ls1tech.com/forums/showthrea...ight=weirdness and will be tweaking it.

Thanks for the info guys!
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Old Feb 21, 2006 | 08:43 PM
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cool man, glad you are getting it figured out. are you talking about in neutral when standing still or when moving?
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Old Feb 21, 2006 | 08:54 PM
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Yes, all the above.
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Old Feb 21, 2006 | 09:02 PM
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shoot me over your bin and i can show you a few more things you can try if you havent already, budchevy358@yahoo.com
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Old Feb 21, 2006 | 09:15 PM
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Hey, thanks for the offer. An email is on the way to you.
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Old Feb 21, 2006 | 09:54 PM
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sent one back you can try out, dont know how well it will work out on your car but you can play around with it
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Old Feb 21, 2006 | 10:14 PM
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Will do. Thanks again for taking the time!
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Old Feb 21, 2006 | 10:18 PM
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no problem
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Old Feb 22, 2006 | 01:03 AM
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Cracker holds the throttle open a little while moving, perhaps to smooth gear shifts etc. So mess with that to sort out idle speeds while moving.

Follower is there to help smooth ramp in and out of the throttle under all conditions so mess with follower decay for when stationary. (And moving) There is an "in gear" and "P/N" table for both situations.

Both cracker and follower can be active at the same time and get summed together.

If you want to try something for fun, try ramping up the follower airflow values, you will get a much better response to the throttle to match your now fast counter drop in rpm.
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Old Feb 22, 2006 | 07:12 AM
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yeah those are the changes i sent him
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Old Feb 24, 2006 | 07:52 PM
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Hey WS6FirebirdTA00,

The changes you sent me worked very well. The idle comes down nice and quick and the idle even sounds meaner for some reason. I need to tweak it just a tad because it wants to go below my set idle speed just a little for just about a second but other than that, it was a nice change. Now I'll be looking at some more changes to the airflow values like ringram is talking about. I'd like a little bit crisper/faster throttle response going up in rpm.
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Old Feb 24, 2006 | 09:03 PM
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does it come down too quick in neutral, gear or both? you can just subtract values from the decay tables until you get it where you like. if you need help just let me know
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