Hello everyone,
This is my first post in this forum, so I'll give a quick self-introduction.
I purchased a 1989 nissan 240sx from a friend for $400. the body is in good shape, but the KA24 is jacked. Around the same time, another friend and i came into possession of a leaky 13b, and a working 13b, and a 13b tranny with a screwy 2nd gear synchro. as i was able to get a hold of all of this stuff for cheep, i will be doing several crazy things to this engine/car. I am an engineering student, and I would like to use this platform for several “science projects” including:
water injection
anti-lag system
(possibly) variable runner length
electric motor assist (purely proof of concept, as i won't be able to afford a good electric motor)
flywheel energy storage system (proof of concept for same reason as above)

and maybe a few more things as ideas come up.

Right now I'm focusing on the anti-lag system. My friend (an electrical engineer) and I are figuring out the best engine management for this project. I'm leaning toward Mega Squirt, but he thinks we can use his HC 11 microprocessor. I think using the HC 11 will be more work than its worth. Any suggestions?

Also, more specifically for the anti-lag, we are not doing a “bang-bang” like in the older WRC cars, we are going to fabricate a combustor, and either run the combustor in parallel to the up-pipe of an over-sized turbo, OR use a dedicated secondary turbo as a turbine engine, the thrust output routed into the up-pipe of the primary turbo in parallel with the normal engine exhaust. This system (apparently) is closer to how the new WRC cars handle anti-lag. I have had bad luck finding much info on the new anti-lag systems, but i guess they work with a combustor and are not nearly as rough on the turbo. The Prodrive P2 had an anti-lag like this i guess. We have already made a fairly well working turbine engine from an IHI RHB5 turbocharger for a thermal fluids class, so we have some idea what we are doing here.
Does anyone have any experience with this sort of system that could offer any suggestions? Is there any particular engine management system that would be more inclined to run something like this (it would involve at least one extra pressure transducer, optic sensor for turbo RPM, and at least one other PWM signal for the combustors fuel injector(s).)

sorry for the long post, I'll try and keep them shorter in the future.

 

Dearborn huh? LTU? UDM?
Sounds like some awesome projects. My only input is to ditch the damn HC11. It may just be my personal hatred for that thing. I know many people are familiar and comfortable using them but it is also waaay outdated. My 17 year old VW Corrado has one in the ECU! Check out the Microchip PIC line up. I bought a PICKit2 for $50 from digikey and I'm using HiTech PIC Lite (free) compiler Just to mess around with.
Megasquirt runs a 68HC908 or a MC9S12 depending on if you run MS1 or MS2. There is alot of documentation on the MS1 for rotarys but only a few die hards working out the bugs of MS2 for the rotary engine. Check out the megasquirt forum under "Engine Management Forum".

For simplicity and style points... I say run a HUUUGE turbo with a divided tang housing. Run the Exhaust to one inlet and the combustor turbine outlet into the other.

Don't forget a combustion chamber thermocouple .

 

UMD, and you?

the twin scroll idea was what i had in mind at first, but i was a little worried about the impeller getting unevenly heated due to the combustor putting out a much lower mass flow rate compared to the 13b over a hard driving cycle. after thinking about it, i figured i would be better off bringing the suplimental exhaust gas in at a 45 degree angle to the uppipe about a decimeter from the turbine housing as to not "freak out" the turbo when the Anti-Lag comes online. maybe i am being too paranoid about it.

also, i had no idea that MS1 had more support for rotaries than MS2...can MS1 do spark timing too? i ask becasue i don't have a 13b ECU at all, and the 13b i have has a distributorless ignition (maybe they all do?) so i'm def going to need whatever ECU i go with to be able to handle everything.

thanks for the input on the HC11, i'll pass it on to my friend. the thing is with him, that he has to buy it for a class, so he really wants to use it on the 13b.

 

Why not use an older HKS VPC/ injector control box- and somehow plumb an addition injector into the exhaust manifold flow side- some what like those flamethrower systems used in the end of the exhaust- sequntially controlled to open when exhaust flow is cut off (inbetween shifts, etc.. closed TB) therefore there is a constant exhuast flow - meaning constant spool- obviously, like every other anit-lag system, they are not good on engines/ and very bad on turbos. Rally cars use them due to necessity, and the fact that turbos/ engines are replaced/ rebuilt periodically. I believe BeeR still makes them, you will have to ship it from japan, but it is a completely individual system, no need for stand alone- just the parts to tolerate it.

 

thats the idea i had when i first started thinking of making an anti-lag system. but where will you get the fresh air to burn with the injected fuel? in the old WRC "bang-bang" the ECU keeps the TB open 20% or so to supply the air, which is ignited in the combustion chamber during the exhasut stroke. this is particularly bad for the head, as the exhaust valves are enveloped by combusting gas. i hear that this is bad on the turbo, becasue its hard to get a "good" combustion when the flame front is traveling through the cylinder/head/uppipe, resulting in explosions of gas IN the turbine impeller, equating to turbo-knock. If i just put a fuel mister in the uppipe, i'll need to get some good air from somewhere, so instead of messing with the TB, i'd rather use a bypass valve. then once i have the air, i have to keep the flame burning steady to keep an even load on the turbine. keeping the flame steady requires a flame holder or "gutter". without this device, the flame would be constantly blowing out, then re-igniting causing a pulse load on the turbine (bad for longevity). i can also tell you from experience that it is very hard to get a flame to light in a high velocity wind stream. we ran into related problems with the turbo-jet before reworking our flame holder. so to get the most steady force on the turbo (and for the flame to light at all), i think i'll definitely need the flame holder.
on top of all that, the geometric nature of the combustor/flame holder allow for a "rim" of bypass air that is not combusted with fuel at all. this acts to greatly reduce the strain on the turbine impeller.
When i go home tonight i'll post some pics of my turbo-jet, especially the combustor/flame holder.

Exiletalon:
i would definitely like to check out that product you mentioned and check out how they did their anti-lag. i didn't get any search results for BeeR though. do you have a link?