Downshifting blips?
04-09-2008, 08:38 AM
#41
4th Gear Member
Join Date: Dec 2006
Location: OK
Posts: 1,888
RE: Downshifting blips?
No, they aren't a truck, and yes, you will find out quickly what an *** end in a rwd car does when you agressively downshift in slippery conditions......it's not pleasant. [8D]
It looks like you are a roadracer from your avatar. Do you really want to tell me that you don't use down****ing when you race?
So, when you coast in gear there is no fuel injected into the engine eh? And pray tell how that happens when your rpms are anywhere from 2k to 6k as opposed to 750?
It looks like you are a roadracer from your avatar. Do you really want to tell me that you don't use down****ing when you race?
So, when you coast in gear there is no fuel injected into the engine eh? And pray tell how that happens when your rpms are anywhere from 2k to 6k as opposed to 750?
04-09-2008, 09:18 AM
#42
2nd Gear Member
Join Date: Jan 2008
Location:
Posts: 334
RE: Downshifting blips?
Wow, why do threads at times take off with chests being puffed out and trying to get everyone to agree with one statement? Heck, I like Almond Joy; not everybody does, does that make it a bad candy bar? I downshift, always have for......OK here is where you can realize that I ain't a young pup, for almost 2 million miles ( that's the well over 1 million i mentioned earlier). I have experienced zero, zilch, no issues from a very diverse set of vehicles.
So, downshift if you like, don't if you like, but be happy with your manny tranny, they do make driving fun.
So, downshift if you like, don't if you like, but be happy with your manny tranny, they do make driving fun.
04-09-2008, 09:32 AM
#43
6th Gear Member
Join Date: Nov 2007
Location: Montaner
Posts: 6,193
RE: Downshifting blips?
LOL this thread is confusing. torque_is_good you downshift when approaching a turn yes? So how do you do it? I'm assuming you don't double clutch then based on the previous posts.
I tried to double clutch a few times yesterday driving around and I think I got it right once. But it seems really counter intuitive when you haven't been doing it for 15 years. Plus I found myself watching the RPM gauge a lot when doing this and it seems kinda... dangerous to be taking my eyes off the road and my mirros when getting close to traffic or making a turn.
I tried to double clutch a few times yesterday driving around and I think I got it right once. But it seems really counter intuitive when you haven't been doing it for 15 years. Plus I found myself watching the RPM gauge a lot when doing this and it seems kinda... dangerous to be taking my eyes off the road and my mirros when getting close to traffic or making a turn.
04-09-2008, 09:43 AM
#44
2nd Gear Member
Join Date: Nov 2006
Location: Caracas, Venezuela
Posts: 401
RE: Downshifting blips?
You do downshift, but not for braking purposes, maybe in the old days when brakes were awful and you needed everything to make the car stop. The downshifting in a road racer is basically a setup for the needed gear on the exit of a turn, some even skip gears doing so 4th to 2nd for example. The thing is that you do it blipping so the downshift wont unbalance the car while you brake, because you are braking hard and have the car on the limit. Specially on our cars that are rear wheel drive and while braking you have the weight shifted forward, so rear wheels can come loose easily under that conditions and always considering conditions of each turn, if you do trail-brake, even more important.
Well the fuel cut off is an usual thing on fuel injected engines, in my fox I had an eec-tuner where you could program your PCM, the injector maps on 0 load were always in 0, I could not believe it at first, but yes, that is how fuel injection works, about the rpms, yes you are going 4000 for example but you have no load so it wont break even there is no fuel. I don't know how exactly this is implemented in the newer cars given the stricter emission requirements, while you coast and fi is off you dont pollute obviously, but cats are getting colder so won't work well once you resume pumping gas. I really don't know if there is a new strategy regarding this in the newer systems.
You can check that easily with your SCT doing a datalogging of you injector pulse in realtime.
Well the fuel cut off is an usual thing on fuel injected engines, in my fox I had an eec-tuner where you could program your PCM, the injector maps on 0 load were always in 0, I could not believe it at first, but yes, that is how fuel injection works, about the rpms, yes you are going 4000 for example but you have no load so it wont break even there is no fuel. I don't know how exactly this is implemented in the newer cars given the stricter emission requirements, while you coast and fi is off you dont pollute obviously, but cats are getting colder so won't work well once you resume pumping gas. I really don't know if there is a new strategy regarding this in the newer systems.
You can check that easily with your SCT doing a datalogging of you injector pulse in realtime.
04-09-2008, 10:01 AM
#45
4th Gear Member
Join Date: Dec 2006
Location: OK
Posts: 1,888
RE: Downshifting blips?
ORIGINAL: Lito
You do downshift, but not for braking purposes, maybe in the old days when brakes were awful and you needed everything to make the car stop. The downshifting in a road racer is basically a setup for the needed gear on the exit of a turn, some even skip gears doing so 4th to 2nd for example. The thing is that you do it blipping so the downshift wont unbalance the car while you brake, because you are braking hard and have the car on the limit. Specially on our cars that are rear wheel drive and while braking you have the weight shifted forward, so rear wheels can come loose easily under that conditions and always considering conditions of each turn, if you do trail-brake, even more important.
Well the fuel cut off is an usual thing on fuel injected engines, in my fox I had an eec-tuner where you could program your PCM, the injector maps on 0 load were always in 0, I could not believe it at first, but yes, that is how fuel injection works, about the rpms, yes you are going 4000 for example but you have no load so it wont break even there is no fuel. I don't know how exactly this is implemented in the newer cars given the stricter emission requirements, while you coast and fi is off you dont pollute obviously, but cats are getting colder so won't work well once you resume pumping gas. I really don't know if there is a new strategy regarding this in the newer systems.
You can check that easily with your SCT doing a datalogging of you injector pulse in realtime.
You do downshift, but not for braking purposes, maybe in the old days when brakes were awful and you needed everything to make the car stop. The downshifting in a road racer is basically a setup for the needed gear on the exit of a turn, some even skip gears doing so 4th to 2nd for example. The thing is that you do it blipping so the downshift wont unbalance the car while you brake, because you are braking hard and have the car on the limit. Specially on our cars that are rear wheel drive and while braking you have the weight shifted forward, so rear wheels can come loose easily under that conditions and always considering conditions of each turn, if you do trail-brake, even more important.
Well the fuel cut off is an usual thing on fuel injected engines, in my fox I had an eec-tuner where you could program your PCM, the injector maps on 0 load were always in 0, I could not believe it at first, but yes, that is how fuel injection works, about the rpms, yes you are going 4000 for example but you have no load so it wont break even there is no fuel. I don't know how exactly this is implemented in the newer cars given the stricter emission requirements, while you coast and fi is off you dont pollute obviously, but cats are getting colder so won't work well once you resume pumping gas. I really don't know if there is a new strategy regarding this in the newer systems.
You can check that easily with your SCT doing a datalogging of you injector pulse in realtime.
In reality it appears that we are on the same page about down shifting. I don't do it so much for the braking effect, rather I do it to be in the power band at all times to have max throttle response available. That is what I mean by control.
04-09-2008, 08:37 PM
#46
2nd Gear Member
Join Date: Nov 2006
Location: Caracas, Venezuela
Posts: 401
RE: Downshifting blips?
On the older cars (EEC-IV), if I remember correctly (about 7 years of that) most of the tables where controlled by load, load is a function of rpm and airflow, lets see if I can explain myself on this you have an engine of certain displacement that is known, and have and airflow meter and also know the rpm regime he is working on. See the engine as an air sucking pump, a given engine at low rpmwill suck less air than it spinning faster, so if you have your engine with the throttle wide open, less say it is at 2000 rpm it generates certain amount of airflow that could be the same with the engine at 4000 but part throttle.
So "0" load means that the engine even spinning at any speed is not sucking air nor doing any job at all, so fuel can be cut off, btw the engine keeps spinning because the inertia of the mass of the car connected via the gearbox that is in gear is moving it. The engine is doing no job at all.
So "0" load means that the engine even spinning at any speed is not sucking air nor doing any job at all, so fuel can be cut off, btw the engine keeps spinning because the inertia of the mass of the car connected via the gearbox that is in gear is moving it. The engine is doing no job at all.
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