Howard Coleman

iTrader: (6)

o k.... those of you w the stock boat-anchor turbo system... you ARE limited to 15 psi on pump. you are limited to 15 psi on racegas. that's because the OEM turbos cavitate (outside edge of compressor reaches supersonic and can't hold on to the air molecules: result super heated low density low oxygen charge from 15 on up) and make less hp.

all others who have discarded their 22 pounds of cast iron- heat sinking- block- frying manifolding and tiny tim turbos and are running around the street w their bigger single knees knocking at one bar.....


you can turn the boost up to 24 psi!

on pump

providing you add some methanol (alcohol) to the mix. it is that easy.

Auxilary Injection (AI) is the answer to actually unlocking all the power that is available from a turbo'd rotary.

or you could run race gas all the time. not practical.

so what has been going on in the rotary community? build a serious setup, throw racegas in it. make big power on the dyno. post your chart. get cheers. then fill it up w pump, change the map and drive around on a crummy 400 hp.

bad plan.

plan B:

go to the Auxiliary Injection section. read up. visit links. spend $500 and have all the boost/power you made on the dyno all the time. with less knock, lower egts and a smiling motor.

i did it this year. the concept and reality matched. read my thread entitled "80% pump... 20% methanol for all the details including installation pics.

BDC did it. he's running 25 psi on pump/methanol.

metrics anyone? how does 1200 degrees F preturbo sound with less than 24 knock making enough hp to go sideways at 79 mph at 60% throttle... i doubt if i will be warping any apex seals anytime soon. saving up for ceramic seals? skip them and buy a stronger clutch

i will make a prediction for 07. AI will have the single greatest impact on the turbo'd rotary community.

we are NOT limited to 15 psi on pump. check out the new AI section if you haven't visited.

howard coleman

RX7 RAGE

iTrader: (22)

good info howard

tiger18

iTrader: (1)

post us a link for this AI section,,,i cant find it ,,,me dumb

Howard Coleman

iTrader: (6)

it is a subsection under the Rotary Performance heading....

the_glass_man

iTrader: (2)

https://www.rx7club.com/forumdisplay...ysprune=&f=173

swif

iTrader: (4)

Going there right now.

With stage 3 turbos from bnr will I be able to get more RELIABLE boost with this set up?

FDNewbie

iTrader: (10)

Hey Howard...thanks for the head's up! Great info...I'll def. be checking out the thread soon. My off-the-bat question is, so what's the drawback? Everything has it's restrictions/shortcomings, right?

Thanks
~Ramy

PS: Congrats; I just noticed you're a mod!

Howard Coleman

iTrader: (6)

yes, just like any upgraded turbo setup you will have lower egts and virtually no knock when properly tuned.

BTW, while i decided to use alcohol (methanol) for my injectant others elect water or a combination...

it depends on your objectives.

run water

run alcohol

run a mix.

what is not smart is to run nothing.

properly executed, Auxiliary Injection (AI) will deliver both more performance (alot more) and much greater engine longevity. do you homework. ask the questions and you will find that AI is for real. just look at my thread and the logs from my runs. the numbers are similar to others running AI and they are spectacular w re to egts and knock.

25 psi on the street


howard coleman

str8ryd

iTrader: (473)

I've been doing a lot of research on this as well and was considering having my car dyno'd on pump with my single turbo and then saving another map for race gas. However, after taking everything into consideration I'm also going the methanol route. AI is the way to go .

charlies7

iTrader: (4)

METH for the win!!

Howard Coleman

iTrader: (6)

hi Ramy,

drawbacks...

before answering your question let me make a point:

there are two approaches to AI.

the first approach is taken by most who just want a cooler motor.... less egt. less knock. longer engine life. generally they opt to run water and a modest amount, around 300 CC/Minute under boost. they do not expect increased power but do obtain greater reliability. since they aren't removing fuel, or raising boost there are no drawbacks given their objectives. a pure win.

the second approach captures all the same reliability enhancement thru lower egts and knock but is pointed toward being able to run 20-25 psi on pump gas.

here is where the "drawback" enters.... in order to run high boost all the time you need to, i use the term "tune up." that is, add alcohol and remove pump gas under boost. if you remove base fuel from your map and your AI doesn't spray alcohol you are will be in need of another motor. that's why i consider it very important to pick vendors and systems carefully.

my system is currently set to start alcohol at 5.5 psi. according to the logs it has not varied by more than a tenth of a psi. i have a 4 gallon fuel cell for the alcohol (see pics in the AI thread entitled Optimized installation) that has a low level light. you do need to make sure you are good to go. there is a test button you push on my system that confirms flow.
as far as i know that's the only drawback.

there are a number of boost-cutter, or ignition failsafes you can buy... i run a J&S Knock detector ignition retarder as a failsafe although i would feel comfortable without it as i have confidence in my system.

howard coleman

Howard Coleman

iTrader: (6)

i don't want to give water a short shift. there are those that have made big power w water by running alot leaner base fuel map. (Rice is one for example). of course they assume the same attendant risk as the alcoholics if the system fails to work.

as i said, run either but run something.

howard coleman

ptrhahn

iTrader: (9)

Where can you conveniently buy methanol though?

the_glass_man

iTrader: (2)

https://www.rx7club.com/auxiliary-injection-173/methanol-where-buy-587251/

Howard Coleman

iTrader: (6)

i found it within 20 miles at 1.99 a gallon. if you have any short tracks near you they generally will know where to get it. you don't use alot of it unless your foot is on the floor and at 20 psi boost there aren't too many opportunities.

i suggest as the single best source of knowledge re AI you visit turbobuick.com and go to the alcohol, propane and nitrous section. there are over 200 PAGES of threads.

a sticky at the top of the section lists a great number of vendors some of which might be near you.

howard coleman

GoRacer

iTrader: (2)

I thought the J&S didn't work (retard) well on a rotary?

How long does your tank last (doesn't sound like much)? I like the low level light but water would be alot easier to get then methanol.

axr6

Thanks Howard for your usual excellent research and information.

I was all set to do a water injection even though I had conceptual doubts about replacing part of the fuel with non-fuel (water) in the combustion chamber. Then, a few days ago I'd read a post here that seemed to confirm my suspicion; that water injection robbed about 20-25 RWHP. Don't know about the exact numbers but, it makes logical sense to loose power if you inject water.

I only intended water as an insurance agains CA's 91 octane. Really do not wish to run much more than 15-16 psi on my brand new BNRs. So, water is on hold now while I'm looking into meth availability and installation. In the meantime I've just ordered a 55 gls tank of VP103. Any idea what would be a safe mix up to 16 psi boost? I'm thinking about mixing for 95 octane that would be a 2:1, 91:103 mix.

Albert

BDC

Nice thread, Howard.

25psi on the street. When I get back up and going, I'm going to hit the dyno and see what it does. This is a Turbo II, btw. And, also, it's running the stock top mounted intercooler. 60-1 HIFI. ~50% duty cycles at 24-25psi at 7000rpm on 720/1680's @ 40psi static.

B

FDNewbie

iTrader: (10)

Hey Howard

Understood. That's the exact understanding I had of WI.

Well I know this is a noob question, but basically in both WI and methanol, the serious "Oh crap" scenario is based on boost w/ an injection failure (ie for some reason, you don't get injection of water or methanol). Why is this such an issue? I'm sure this is a huge oversimplification, but given that there are a good # of ECUs that can handle multiple fuel rails and complicated fuel systems, and we're already set up for multi-fuel pump systems, why can't one design a methanol "fuel" system w/ it's own injectors and rail, ie the whole 9, pulling from a methanol tank, etc? Basically a complete separate stand-alone fuel system based on proven fool-proof fuel delivery system, instead of relying on nozzles, pumps, sprayers, in what seems to be (IMHO) to be a makeshift kit (vs. going all out and making it fail-proof)?

Peter, check these guys out: http://www.methanol.org/ Being that they're based locally, I'm pretty sure they'll have a pretty good idea of where you can source methanol...

Improved FD

nice work Howard and Brian, you guys are pioneers (ok that sounds kind of cornball, but true)

we need alot fewer "oops, I popped my engine" threads around here...this sounds like the ticket

snub disphenoid

I'm glad that you and others are so thoroughly exploring AI, I think it's going to help a lot of the power-hungry people out there.

Would there be any troubles with the motor holding together? I know that the TII engines like to crack irons left and right once you get past 20 or so PSI on a stock motor, but would an FD engine's integrity be compromised by running this much boost and making that much power? Or does the fact that alcohol lets the motor run a bit cooler compensate for that? I'd be interested in seeing how well the motors actually physically stay together because everyone's "common knowledge" has pointed to motors actually twisting and separating plates above ~17psi on an untouched engine.

I say this because I have a reman, and I'd like to turn the wick on my Knightsports twins up to 16-17 psi, but wouldn't want to do so if there's a good chance of something like cracking an iron. I realize that a failure-proof (or as close to failure-proof) ignition, fuel and AI system would be necessary, as well as a very competent tuner, but outside of that, do "plain physics" as some have stated actually come into play at 20psi on a stock motor?

Fsunoles06

Is WI really going to rob that much rwhp? Can someone give more of an explanation.

Howard Coleman

iTrader: (6)

i am delighted that my post stirred some interest.

various questions were raised and i will do my best to answer them but before i do let me mention that an ongoing debate continues w regard to water v alcohol. it sometimes reaches sheepherder/cattlemen proportions and is inevitable.

after an initial general exposition, AI generally lurches off into pages and pages of half truths, supposition and even a little hyperscience that most (including myself) ultimately don't understand.

so let's do something different than all the other boards and focus on the reality of AI as the benefits of it are way too HUGE to get lost in blah blah blah stuff.

and the reality is:

all motors when turbo'd become thermally challenged.

heat limits boost ultimately.

Heat: piston v rotary

i have raced (SCCA NATs for 22 full seasons) both piston engines and rotaries. in normally aspirated form my full (road) race piston engines made best power at 1322 degrees egt. my Daryl Drummond & Roger Mandeville GT3 rotaries made best power at 1750 egt both measured approx 4 inches from the exhaust port. BTW, my rotaries were all dry sump, and ran between 7000 and 10,000 rpm for 35 minutes w either my right foot on the floor or the brake. the point is the rotary produces a lot of HEAT along w power.

AI solves the Heat problem and it will, properly applied, solve the rotary longevity problem freeing the motor to make huge power v the piston engine.

I elected to run methanol as my AI injectant and my current tuning challenge is to RAISE MY EGTs, as they are between 1150 and 1200 and i am making, not completely tuned out more than 500 hp. 1500 egt is my target so i will be leaning it out by removing additional pump from my map and replacing it with methanol.

How much cooling can you get w AI?

my friend Jose LeDuc runs a 2 rotor RX3 drag car in NHRA's pro RWD class. i think he has to weigh 2000 or 2100 pounds. he has run 7.7 at 179 mph w his 13B on 100% methanol.

HE DOESN'T RUN AN INTERCOOLER and is making (classified) way over 900 rwhp. you don't want to put your hand on his intake manifold after a run as it will get stuck (frozen) to the manifold. that's on 100% alcohol.

Executive summary:

Water cools.
Alcohol cools.

so the rotary is thermally challenged and heat accounts for:

most engine failures due to knock

limited performance due to lousy (pump) fuel, i e your engine would love to run 20 psi but you can't as you would run into too much knock above one bar on pump.

AI can solve both problems.

if you want to cool your motor so it runs egts like a piston engine and are generally happy w one bar boost water is the most direct solution. if you elect not to change the boost or the timing water will deliver a knock free motor at the cost of 10-20 hp. a nice tradeoff for many of us especially those running the OEM turbosystem. The advantage as to not changing your tune is no harm will come to your motor should the AI system malfunction.

Cost would be another advantage as you could build your own system or purchase a cheaper system since if it were to fail it wouldn’t cause engine failure. DIY can be done for under $200. inexpensive water systems start in the $200 range and can escalate depending on features to $500

Alcohol is a whole ‘nuther thing. Most “tune up” when using alcohol in that they remove pump and replace it w alcohol. I am close to 40% alcohol under boost. If the alcohol malfunctions it is good-by motor. Therefore system integrity is paramount. Methanol, the most advantageous of the 3 alcohols, is corrosive so aerooquip lines w brass fittings are necessary as is a replacement of certain items within the system pump. I do not know what goes on in the pump as to mods as I elected to buy my system, install it and tune it not re-invent it as system failure is not an option.

So far, pro forma. I adjust at what boost I want the alcohol to start. I adjust at what initial pump pressure I want and I adjust the progressive ramp of the boost relating to the MAP sensor voltage. I then adjust my fuel map to get the AFRs I want which will be around mid elevens. I fine tune (Power FC Datalogit) with base fuel.

I run a twin TO4 turbosystem that I designed and built that makes 84 pounds per minute, about the same as a GT42, but at 17-23 psi instead of 29 psi+. I have run 18.7 psi and am leaning it out and am around 10.5 afr… too rich.

Unfortunately, I exceeded the limits of my Exedy Hyper Single on my last run and will have to upgrade so my car is down for the Wisconsin winter. My entire tuning metrics are in a thread in the new Auxiliary Injection section near the Rotary Performance header. Check it out if you want real world details including installation pictures.

As to the posted questions:

Go/racer… as to the J&S knock sensor not working too well w rotaries… actually, if you have the later model that has a MAP sensor built in it works great. Since we often run no split in vacuum the J&S, with it’s 10 degree retard of only the leading plugs needs to function only in boost and only w a split larger than 10 degrees. The boost sensitive MAP allows the retard only under boost when you have the split. I haven’t encountered any knock yet but expect it to retard if it sees knock.
.
AXR6… yes water will cost a modest (10-20?) hp if you don’t change tune. Sorry, can’t answer the VP103/91 mix question for you.

Ramy… stand-alone AI. Yes, that is the future for AI but the current systems work very very well. The better ones are plug n play and should not be considered makeshift.

Improved FD… “less popped motors” you bet… less heat, less knock

Snub disphenoid… maybe BDC will comment as he would know.

Fsunoles06… again, if you simply add water to cool things down you will make a few less horses but take a few hundred degrees out of your egts.

howard coleman

axr6

First, thank a million to Howard for doing the work for us and taking the time to share all his findings, aswer questions etc...

Looks to me that if one wants to limit the boost to about 15-16 psi, water injection might NOT be the BEST solution. If you loose the suggested 20-25 HP (I had seen up to 33 HP claimed loss due to water, referred to in the AI section) you are basically negating all the power gains from 2psi boost thus, your running the equivalent performance of a 13-14 psi boost, someting that is considered fairly safe with pump fuel, without injection. I've been running there now on 91 with very low knock numbers on my PFC.

Now, if you're aiming to go much higher boosts, such as 18 or over psi, than it makes all kinds of sense. At 20 psi, including you power loss due to water, you gain an equivalent performance close to 18 psi. Yet, 18 psi is widely believed to be beyond the safe levels of pump fuel only. Still, using posted info from the AI forum, you will lose that power with water and will loose less than half of power (compared to water) with methanol. So, looks to me that if I decide to continue with my AI project it will go to full meth and not water.

Thanks again for the great thread here and on AI

Albert

adam c

iTrader: (2)

Very interesting and informative thread. Thanks to all who have posted.

I have what may be a stupid noob question: If methanol helps to safely allow higher boost levels, why not just add some into your gas tank?