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-   -   NO More Turbo lag !!! (https://www.rx7club.com/single-turbo-rx-7s-23/no-more-turbo-lag-94174/)

TriTurboGen3 RX-7 07-06-02 02:33 PM

NO More Turbo lag !!!
 
Check this shit out, this type of system is used on world rally champoinship cars. there is a drawback expect tho expect to Rebuild your turbo every week and replace the bearings cartridges. All teams use what they call an 'anti-lag' system. When the driver lifts off the throttle, the ignition timing is severely retarded, an above normal amount of metered air is allowed to enter the engine and fuel is injected between the exhaust valves and the turbine inlet. The ignited fuel creates heat that keeps the turbo speed up. When the driver re-applies the throttle, there is an explosion of raw fuel in the turbine that sounds like pistol shot, a burst of flame, and voila, no lag. This system can be switched on or off or modulated by a switch on the driver's control panel. i would love do that cept the cost damnit.

relvinnian 07-06-02 03:09 PM

http://thelittlebaby.dhs.org/kenny/sweet/lastweek.jpg

Sorry, couldn't resist :)

TriTurboGen3 RX-7 07-06-02 04:27 PM

ok well its new to me, i haven't seen anyone on any site with car do it, so its news to

Greg 07-06-02 04:30 PM


Originally posted by TriTurboGen3 RX-7
ok well its new to me, i haven't seen anyone on any site with car do it, so its news to
exactly, there are new member joining everyday that have no clue about stuff like this.

TriTurboGen3 RX-7 07-06-02 06:06 PM

So why hasn't anyone tried it? cuz the cost of repiars ??

cyanide 07-06-02 06:16 PM


Originally posted by TriTurboGen3 RX-7
So why hasn't anyone tried it? cuz the cost of repiars ??
i dont think anyone has the money to rebulid their turbo every week :rolleyes:

maxcooper 07-06-02 11:27 PM

There is some anti-lag stuff in the PowerFC/Datalogit setup, too, but I haven't played with it yet.

Max

TriTurboGen3 RX-7 07-06-02 11:41 PM

Schweet thanks gmonsen, does the haltech feture work the same as i mentioned above or, is it safer for your turbo, and if it does work they same, wouldn't i have to Set up a a fuel line to the exhaust Manifold? thanx for the info.

1FooknTiteFD 07-07-02 05:12 AM

Some of the high end FMU's can do this. Anyone watch initial D before? this is the exact system the Mitsubishi Evo 3 had in it's car dubbed the "misfiring system" I heard that it only works on certain turbos though.

HWO 07-07-02 05:47 AM

you cant run WRC style anti lag on a rotary, because the rotor is too far round past the spark plugs to fire it miles after TDC to get the flame front straight out thru the turbo. The Hyundai WRC cars run 45psi boost at 0% throttle from antilag.

What they do is have a high flow solenoid which by passes the TB and flow enough air to keep the motor running when its running at like 30-40 degrees after TDC, they run like 20% enrichment when the antilag is acvtivated so you get combustion thru the exhuast manifold and into the turbine. It melts turbine wheels from prolonged usage (ie a rally stage) they thru the turbo's away after each rally

TriTurboGen3 RX-7 07-07-02 04:27 PM

Ok screw that idea for my car, so how do the electronic version of this sytems work, how could a computer type component eliminate Turbo lag?? I'm confused. i got another question tho, its not exactly related to the topic, i know the difference between a Wastegate, BOV, and SSBOV, but what is best? and is my understanding correct that a wastegate would do just as good as a BOV up to 400hp ?

AJatx 07-07-02 05:15 PM

Anti-lag or as rally guys say "bang bang" has been around for quite some time. There are a few rotaries using anti-lag (as Gordon mentioned, a few from the Haltech list like Horatio from Jamiaca). I've heard of good results as well.

Steve Kan may have used anti-lag since a friend has heard his boost spool on the line.

You will shorten the life of the turbine. I think some people may over exaggerate damage as they are only guessing off hearsay.

Wastegate and BOV are similar mechanisms and functions, but very different application.
Wastegate basically vents out the "wasted" exhaust pulses through the gate into the exhaust; therefore, bypassing the turbine. A boost controller controls the top of the wastegate diaphragm to control the upper limit of boost.
Blow-off valve (or air bypass valve) will release the compressed air that is being made by the compressor wheel of the turbo charger as the throttle plates shut (letting off throttle) so as to prevent compressor surge (not good).
So, both will vent out air (exhaust or intake), but different application (limit boost vs. preventing compressor surge).

Your last question makes no sense to me.
BOV has nothing to do with horsepower. You set the spring tension so it'll vent out the compressed air at a desired boost level (soft -> less boost; hard -> high boost).
The wastegate has a spring in it as well that determines it's natural release point (14psi spring will compress at 14psi; thus the wastegate releases the exhaust at 14psi thereby holding boost at 14psi -- theoretically). The wastegate discharge diameter can play a factor on how efficient the wastegate can dump the wasted exhaust (40mm v. 50mm, etc).

Sorry for the long reply.

J

TriTurboGen3 RX-7 07-08-02 02:01 PM

Well i've seen on a few websites, and posts, that wastegates will be efficeint up to 400hp or like 15-17 psi. is this correct ? Thanx i appreciate the long post, means i learn more

DARKcrenso 07-08-02 03:27 PM

I use a anti lag system called NOS.

maxcooper 07-08-02 06:40 PM


Originally posted by TriTurboGen3 RX-7
Well i've seen on a few websites, and posts, that wastegates will be efficeint up to 400hp or like 15-17 psi. is this correct ? Thanx i appreciate the long post, means i learn more
Wastegates and BOVs do two different things -- AJatx described each of them well. Some particular wastegates and BOVs are only good up to a certain HP level or boost pressure. But these parts do different things, so you wouldn't buy a BOV if your wastegate was inadequate -- you'd get a different wastegate. Similarly, if your BOV can't handle the pressure, the only solution is to get a different BOV (or eliminate the BOV from the system entirely).

Wastegate is for boost control. All turbo cars have them. This is THE device that controls boost; nothing else does this job but the wastegate. Electronic boost controllers and other boost control devices just modify the control signal to the wastegate (which is one or two air/vacuum lines) -- it is still the wastegate that controls the boost pressure.

BOVs are for preventing compressor surge. Most turbo cars have them. They make the pssss noise when you let off the gas.

They serve different purposes, and just about everyone with a turbo on this forum has both devices.

-Max

TriTurboGen3 RX-7 07-08-02 07:53 PM

Ahh ok thank u, i was confused, cuz i listening to some guy who lives around here, and owns a riced out civic, but he seemed to know what he was talking about when i acually met him. I guess i was right, he's full of it.

peejay 07-10-02 09:54 AM

hey now, not ALL cars have wastegates :) Some early turbo kits (and many diesels for that matter) ran what is known as a free-floating turbo setup - the turbo is sized so that it doesn't build maximum boost till near redline. Exhaust and carb restriction also came into play.

The Diesels are a different story - they're funny engines, for a given amount of fuel, they run cooler with more air, so it's best to just let the turbo spin up as hard as it wants.

spyfish007 07-10-02 01:34 PM

I know of certain diesel trucks that have two turbos and no wastegates or blow off valves. Don't need the BOV if you don't have a throttle plate.

Marcel Burkett 07-10-02 06:40 PM

The anti - lag system can work on a rotary , the claim that the " rotor is too far round the spark plugs to fire it " is incorrect , what actually happens is , when the feature is engaged the computer retards the ignition a pre determined amount to allow "raw" fuel to pass through the engine and into the very hot turbine housing where it is ignited by this heat just like a "back fire " from the muffeler.,this ignition is what causes all the strange noises and what also makes the turbo spool up due to the sudden and massive expansion of the gasses after the explosion.If you select the ignition retard featutre as your means of rev. limiting on the E6K you would see what I mean.:)

HWO 07-11-02 01:14 AM

there are many different ways of running antilag, some do work on a rotary, others do not.

pluto 07-11-02 05:22 PM

Anti what???! LOL :D :D :D :D :D




Originally posted by HWO
there are many different ways of running antilag, some do work on a rotary, others do not.

R Xplicit 07-11-02 08:36 PM

how about a quick 25-50shot of spool-up juice. many drag racers are usng it....right?

peejay 07-12-02 01:52 AM

On every upshift? :)

UnSeeN 07-16-02 03:44 AM


Originally posted by 1FooknTiteFD
Some of the high end FMU's can do this. Anyone watch initial D before? this is the exact system the Mitsubishi Evo 3 had in it's car dubbed the "misfiring system" I heard that it only works on certain turbos though.
haha..i was thinking the same thing..


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