Tuning drop throttle response
I just went out and tried some settings. Here is what you need to do OP,
Go to table b1829 and from 6000-4000 rpm Put in -64 for the values in the gears you want it to pull down fast.
That is a NEGITIVE 64. "-64"
Then on the coast down table pull 15 deg from the table at the higher rpms. B5122.
That allowed my heavy car come down very fast.
Go to table b1829 and from 6000-4000 rpm Put in -64 for the values in the gears you want it to pull down fast.
That is a NEGITIVE 64. "-64"
Then on the coast down table pull 15 deg from the table at the higher rpms. B5122.
That allowed my heavy car come down very fast.
Thread Starter
Teching In
Joined: Dec 2005
Posts: 26
Likes: 0
Thanks very much!
As far as inertia goes, it is very significant, which is why i am doing a light flywheel. But the vacuum is largely constant with cid. The inertia is not just the flywheel. It is all rotating accessories if the car is not in gear. In an lsx that is probably 150-200lbs depending on what flywheel and crank you run, though the flywheel is the largest diameter. In your top fuel example, it is the entire weight of the car at 300 mph. Of course it will keep spinning.
As far as inertia goes, it is very significant, which is why i am doing a light flywheel. But the vacuum is largely constant with cid. The inertia is not just the flywheel. It is all rotating accessories if the car is not in gear. In an lsx that is probably 150-200lbs depending on what flywheel and crank you run, though the flywheel is the largest diameter. In your top fuel example, it is the entire weight of the car at 300 mph. Of course it will keep spinning.
Thanks very much!
As far as inertia goes, it is very significant, which is why i am doing a light flywheel. But the vacuum is largely constant with cid. The inertia is not just the flywheel. It is all rotating accessories if the car is not in gear. In an lsx that is probably 150-200lbs depending on what flywheel and crank you run, though the flywheel is the largest diameter. In your top fuel example, it is the entire weight of the car at 300 mph. Of course it will keep spinning.
As far as inertia goes, it is very significant, which is why i am doing a light flywheel. But the vacuum is largely constant with cid. The inertia is not just the flywheel. It is all rotating accessories if the car is not in gear. In an lsx that is probably 150-200lbs depending on what flywheel and crank you run, though the flywheel is the largest diameter. In your top fuel example, it is the entire weight of the car at 300 mph. Of course it will keep spinning.
As for the inertia from the accessories, it is largely insignificant. Because it doesn't carry the weight of the flywheel, and it's not hanging off the end of the crank. The whole purpose of a flywheel is inertia. Ever try to start a lawnmower without a flywheel or blade? The whole purpose of a flywheel is inertia.
http://en.wikipedia.org/wiki/Flywheel
Thread Starter
Teching In
Joined: Dec 2005
Posts: 26
Likes: 0
Yes, in my TF example, it is the entire drivetrain spinning the engine, which is a good example of what happens when you try and engine brake a car.
As for the inertia from the accessories, it is largely insignificant. Because it doesn't carry the weight of the flywheel, and it's not hanging off the end of the crank. The whole purpose of a flywheel is inertia. Ever try to start a lawnmower without a flywheel or blade? The whole purpose of a flywheel is inertia.
http://en.wikipedia.org/wiki/Flywheel
As for the inertia from the accessories, it is largely insignificant. Because it doesn't carry the weight of the flywheel, and it's not hanging off the end of the crank. The whole purpose of a flywheel is inertia. Ever try to start a lawnmower without a flywheel or blade? The whole purpose of a flywheel is inertia.
http://en.wikipedia.org/wiki/Flywheel
The only difference between any mass connected to the drivetrain with respect to inertia is the moi, largely dictated by diameter of the weight. Ac, alternator, crank, valves, driveshaft etc are all part of the total moi equation with the flywheel. Thus taking 20lbs off the fw may only be 10% of the total mass though probably more % of moi due to diameter.
Perfect example, unbolt a torque converter and start and rev an engine and see how fast it accelerates and decelerates.
Last edited by edcmat-l1; Mar 7, 2013 at 07:06 PM.
Thread Starter
Teching In
Joined: Dec 2005
Posts: 26
Likes: 0
I just went out and tried some settings. Here is what you need to do OP,
Go to table b1829 and from 6000-4000 rpm Put in -64 for the values in the gears you want it to pull down fast.
That is a NEGITIVE 64. "-64"
Then on the coast down table pull 15 deg from the table at the higher rpms. B5122.
That allowed my heavy car come down very fast.
Go to table b1829 and from 6000-4000 rpm Put in -64 for the values in the gears you want it to pull down fast.
That is a NEGITIVE 64. "-64"
Then on the coast down table pull 15 deg from the table at the higher rpms. B5122.
That allowed my heavy car come down very fast.
Thats great info. I dont think we were brave enough to try a negative. I'll try that. Thx.
I went thru the assembly last night that I had done in idapro originally when mapping out the tables/calls for this controller type, and it looks to be that a negative number in the table will call for a negative torque request. If it is 0 or higher it calls for a positive torque request. Hence when at idle and you need more airflow, you add to that table and it adds it. A value of 0 would be free rev it looks like with no throttle help. Neg will pull it down via throttle blade.
Thread Starter
Teching In
Joined: Dec 2005
Posts: 26
Likes: 0
well, the 23 lb clutch/pp/flywheel assy is in, down from 57, and without any tuning, it does rev up a bit quicker, but certainly does not drop throttle any quicker. which ends the inertia v. throttle position tuning debate. i will try some negative values as wait4me posted and let you guys know what happens.
now, with the GS transmission and light flywheel assy, getting the power down in 1st and second gear coming off corners is the big issue. I assume you can tune throttle OPENING rate v. pedal position pretty easily. I will do a search, but any info is helpful.
now, with the GS transmission and light flywheel assy, getting the power down in 1st and second gear coming off corners is the big issue. I assume you can tune throttle OPENING rate v. pedal position pretty easily. I will do a search, but any info is helpful.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Has nobody here driven and old school carbed hot rod? Even with a heavy flywheels, rotating assembly, and driveline parts the engine deceleration when closing the throttle is dang near instant. The goofy LS electronic controls has long been a complaint of mine too during engine deceleration.
