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Discussion Starter · #41 ·
from bean
james you are looking at this the right way, higher boost off the bottle,and lower boost on the bottle. i use a blitz dsbc with 18 psi as my high off n2o,and 16/15 psi on the bottle. yes is it adjustable on the fly, right now i use one of my four settings for driving to work set at seven psi (gas saver)and any time i want some pep i just turn the knob one click to the left and im at 16 psi. i still love my twos'r'us mbc but i needed adjustment on the go with zero by the side of the road late night tuning.a ebc is almost a must in my book when using nitrous,due to the safety features built into the unit. let me know if there is anything else i can help you with. be
 

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Discussion Starter · #42 ·
from bullwinkle
Cheers Bean,

Just what i wanted to know. I knew it could be done, but over hear all the nitrous tuners just say run no boost and all nitrous. Which only makes my car fast for 5% of the time.

I will have a look into boost controllers to finda suitable one, but you reccomend the BLITZ DSBC? Would the Apexi AVCR be suitable, i dont know if it can be switched bewteen settings.

My friend owns a Jap import conversion garage and he has loads of spares which get taken off the cars before sale, i know he has got a spare HKS EVC 4 which i could blag, would this be suitable?

Havent really looked into EBC's as i was always planning on a full standalone, but my view has changed and now i know i can get the performance figures i want without having to spend ????? on a new turbo and EMS.

To coin a phrase i want a Jekyl and Hyde car, 300 odd bhp for the road and considerably more with the giggle gas for the track.

Out of interest when you change your boost settings i take it you do this when you off the turbo (not boosting) Am i right in thinking that you cant for example drop the boost from 18psi to 16 psi when your going for it (for example a road race) to engage the nitrous.

Not that i would use the nitrous on the road but i really want to know the limitations of this set up.

No for the sad part .. what sort of shot could i run on my car considering all is well and good. The unit is a Rev3 3SGTE with stock internals and CT20 turbo. If for example i ran a 50 shot would that be more like adding 75bhp, as i benifit from better charge cooling as a result.

Bearing in mind my car makes a wisker under 300bhp / 278lbs/ft at 1.2 bar with the mods i have listed on the previous post, would it be possible for my car to make near on 400bhp with dropped boost and nitrous?

I want to have the fastest 1/4 mile MR2 in the UK

You advice is really appreicated.

Kind regards

James
 

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Discussion Starter · #43 ·
from bean
bullwinkle, with the blitz dsbc you can toggle between preset boost levels when boosting.i have never used,installed,or tuned a apex avcr so i have no facts to state about it other than it is also a ebc.if you go after market ecu i do know the aem plug and play will also taylor boost settings for you.

and just for the record your nitrous should be tuned to a specific psi/bar well within the 11.5-11.8 air fuel ratio,and i would not have the system active when switching different boost levels.
as for the shot always start small and work up from there.
a 50 shot wet on the 3sgte will make 80~90 rear wheel horse power



james


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Discussion Starter · #44 ·
from bullwinkle
After thinking about this i think i will go for a piggyback rather than a full standalone. The DASTEK unichip fits my goals for the time being, really inexpensive and will allow my cars fuel and timing to be adjusted for the road (without Nitrous) and for the track (with Nitrous) - from discussions with a turner in the UK who works with these systems it can also be activated on the fly to change settings.

I will investigate futher into the EBC subject as the DASTEK unit that i intend to go for at the moment dosnt have the best boost control. Hopefully the AVCR will allow me to change settings on the fly, i would prefer this unit for boost control as you can set boost by gear which should help with off the line traction.
 

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Discussion Starter · #45 ·
from bean
bullwinkle, thanks for clearing up some items for me. i would think your ignition is like the usdm gen 2 with adjustable timing,right? if so then you should be okay with the timing issue,depending on which kit you buy you may have to retard timing 2 degrees.(also msd makes some nice timing control boxes) and as for fuel tuning i have found after much research the adjustable fuel pressure regulator from areomotive is the way to go because, it will adjust base fuel pressure lower than stock to lean out the car. the us gen 2 is a pig rich baby,how is yours? be careful of what black box you install because it may advance engine timing like the apex afc.
 

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Discussion Starter · #46 ·
from todd t
Just thought i'd add to this since i have experience with street and race nitrous equiped cars, including my 93t.

On my car:

NX universal EFI import wet kit
swapped the 14ft feed line for a 4 ft line
NX purge kit
NX bottle warmer
NX 15 lb bottle upgrade
Throttle switch activates at WOT, no manual control

I was formerlly "sponsored" by one of the biggest NX distributors in TX due to my former involvement in the street racing seen. I got the best of everything because i only paid for 1/4 of the stuff and they wanted me to have it all.

Bottle Warmer is not something i would consider necessary for the mr2 because of the location of the bottle (trunk) and the constant somewhat high temperatures back there, bottle pressure was always consistant and i never needed the warmer.


Purge kit is very cool. without purging, nitrous delay can be a couple of secconds from when you activate it to when it reaches the combustion chamber and the fuel can hit first causing fouling plugs and/or bogging the car and worst would be nitrouse backfire through the throttle body Also, if someone pulls up to race you on the street and you are not in the mood, you cound sound off your blow off valve follow be the purge and 99% off the time, they will change there mind (my favorite part)

I do not recommend using the nitrouse before 3k rpms, hopefully you dont race at that low rpm anyways.

if you are going to spray 75HP or more, it would not be a bad idea to get a fuel cell and put race gas in it. You will need to buy the cell, pump, regulator and necessary hardware, but this will decrease chances of detonation. You will also have to rejet the kit to match the fuel pressure you chose to run.

I was running 50HP nitrous shot into my t3/t4 equiped mr2 at 16psi boost with stock engine and no fuel or timing control and was still running a little rich.

Do yourself a favor and install a good clutch before you buy your kit, you will kill your stock one quickly!

thats all i have time for, if anyone needs help, i will try to answer your questions, just send me an email
 

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Discussion Starter · #47 ·
from bean
it must be hot in texas because my bottle pressure ranges from 600-800 with no heater,i have to use a heater to attain my 1000 psi and hold it. mabey due to my white trunk reflecting sunlight or its just colder in san diego.who knows. but i still recommend it to n2o users. its good to see more people adding information to this post, thanks again to all who have put words of wisdom into this thread. and there is much more to come. james
 

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Discussion Starter · #48 ·
from icyjaws
what about a cleaning effect? I've heard diff views on this. Does N20 have a similar effect as h2o injection? Will it actually "clean- up" the carbon deposites? Like I said I've heard both it will and it wont what up?
 

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Discussion Starter · #49 ·
from bean
some n2o people swear by its cleaing effect but, i have found that it is tracable and leaves a white sulfer residue. when i was using the kit to cool the inter cooler the spray would enter the cab and coat everything with a sticky film of sulfer. and it does not taste good. my next hunch is that the residue will build up causing the wastgate door to not propery close and cause boost problems. we will see after many more pounds and my next turbo pull.

NOTE: to all new n2o people and posters please take the time to read all the pages in this thread because there is a lot of info already covered.
james
 

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Discussion Starter · #50 ·
from pontiac5oh
so, mr.bean...im posting in the n20 section. i have the stock ct-26, no clipping etc. and am running 17psi, no problems for 20k+. i can run more than 12psi with the juice? i just can not afford a new motor or anything major breaking. i have the 120k tune up. new wires, plugs, dizzy, tbelt, clutch, rear main seal, flywheel...etc. should i swap to colder plugs? i just dont want to get any false info, and then blow my motor. so i cna keep stock timing and run what...15psi with a 50 shot? i ran a 13.5, and run mid 13s consistantily with my mods (see sig), can i expect mid 12s? or high twelves?
thanks a bunch, this sticky was great to read b4 posting.
tyler
 

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Discussion Starter · #51 ·
from bean
Tyler,turn your boost down to 13 and try a 50 wet,you should be around 17 psi. the only other factor that comes into play is how free your exhaust is.you may only get a 2 psi jump in boost,so start slow and low and build up from there. im still playing with my system trying to figure out whats making more power high boost and low n2o,or low boost big shot of n2o. right now im leaning to low boost more juice. even on the bottle your stock turbo is going to fall on its face at 5500 rpm's,so you may want to upgrade in the future.okay now for the serious part my mr2 is my daily driver to work,40 miles a day so I can not afford to break my engine either. no one wants to blow a head gasket or break pistons so WE are in the same boat. right now i run 18 psi on 91 pump gas with now problems to report other than bad milage.think of it this way boost is boost and psi is psi, so if you are on the bottle hitting 17 psi its the same as hitting 17 psi all turbo just ALOT colder air.and again you will not have to retard timing if you use nitrous works or nitrous express kits. please go 1 or 2 steps colder than stock with the plugs. what clutch do you have? when you go back to the track you should see 3/10's off your time, IF THE CAR AND NITOUS IS TUNED PROPERLY .
And one more note the NX kit cost 2-300.00 more than nitrous works. you and your car will be fine,and feel free to e-mail me anytime you have questions regarding your install and tuning.


bean
 

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Discussion Starter · #52 ·
from gotime242
Man, you really love your nitrous works kit!

Hey man, im in the same place as well. My mr2 is my daily driver, and if something goes wrong i would have to whip out the old bicycle. So like bean said, no one wants to hurt their engine.

The engine can take it, i have about 120,000 miles on my engine with stock turbo and run 14/15psi with a 50 shot all day long. Creep usually pushes me up to 17 psi. I would recommend you use -----> Ngk BKR7E plugs. This is what i use, and with great results.

Its always a good idea to start slow, not exactly for your engine, but for you as well. Just so you know how things go, and the affects it has on everything. I started at a 35 shot @ 4 psi, and worked my way up to what im doing now.

Im thinking about running a 75 shot myself, but i have taken out everything i need to around here, so if one of my buddies beats me some day, then i will up the shot.

So, i hope i have helped, good luck. Later man.

-Dylan Shine
 

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Discussion Starter · #53 ·
from bullwinkle
On my quest for nitrous i have stumbled across a NX kit going cheaply from a contact i know. I was just wondering on whether these kits are any good or not. I am still waitoing for a reply on the kit specfics but would be interested to know if the NX is a worthwhile nitrous system.

Talking to a few UK based nitrous users, the advised me that i wouldnt have to lower my boost to run nitorous. I know you reccomend otherwise. Just want to check this out as its not their engine thats going to go bang if they are wrong. I was told that my boost could be kept at 1.25 bar and the nitrous could be run at the same time. I have been told that with the correct electricals (wires and plugs) i could run a 100bhp shot. Also I wouldnt have to retard timing if i opted for a progessive controller, which means the off gas performance isnt affected.

What are your views?

Cheers

James
 

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Discussion Starter · #54 ·
from gotime242
Well, first off, not only is Nx a great kit, i consider it to be the best. Its what i have on my car right now, and is what i would recommend to anyone, and even more so if their car is turbo. They have outstanding nozzel design, and high quality parts. As well as great customer service if you ever need it. Nx is definetly the way to go.

As far as your next question, boost needs to be lower to compensate for boost creep. That is one of the main issues. I would honestly not recommend you run a 100 shot. Some people have, one on this board for sure, and have gotten away with it. But i woudl still never try that myself. The oem toyota ignition components are fine for what you are looking to do however, just make sure they are new or up to date. The plugs however do need to be changed, you need to go a range or two colder, as well as go copper. I use Ngk Bkr7e plugs, And love them. But, like i said you dont need to get performance wires or anything.

Regarding retarding the timming, with a Nx kit, you do not need to do so for smaller shots such as 50-75. But after that, yes you do have to retard it a couple degrees, aprox 2. And about lowering the boost, all you really need to lower it for a 50-75 shot is a psi or two. Im running 14.5 psi with my 50 shot, and all is well.

So, please if you have not so already, read what is already in this thread, and what we have stated before. Im sure this has all been covered in these 100 pages of nitrous talk.

Final note: go get that nx kit and have fun. Start small however so you know how everything goes. I hope i have helped, good luck, and let us know how things go. If you have any other questions, dont hesitate to ask.

-Dylan Shine
 

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Discussion Starter · #55 ·
from sallystrothers
I have RPM dependant timing retard. I think this is the only thing that has kept my engine in 1 piece. I go from -2 deg @3500 RPM to a -5 deg @7000. This actually has helped give more power. I have less detonation with the retard. And I will never run over 10 psi while on the bottle, why boost more when I break traction in 2nd and 3rd gears ?
 

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Discussion Starter · #56 ·
from bullwinkle
GoTime242, thanks for the reply. The problem is a read postingsa on this site and then i get told somthing totally different when i ask about it in the UK. I have spoken to the UK largest nitrous tuner and installer about what i require. He advised that my boost didnt need to be lowered, and that i could run the nitrous ontop of my usual 18psi.

This took me by surprise as its totally different to what i have read. The tuner didnt seem at all bothered with the fact that i could run 100bhp, he was the one that suggested i could go that high depending on the quality of my electricals - he suggested high quality leads, cap, rotor arm and plugs (which have all be addressed - stage coler plugs as well)

I was told that i only needed to retard the timing to accomodate nitrous if i intended in firing nitrous in one shot. If i used a progressive controller then this wasnt needed, i have also heard of retard switches which will kick the timing back to accomodate the nitrous when needed.

I was also told that nitrous dosnt create more boost. Now this is where i hit a brick wall. You see looking at it from what i understand from tuning a turbo - a new intercooler would create a slight boost increase due to better cooling. Now Nitrous would do just that create a cooler charge and hence boost would go up, but on a much bigger scale. So yes it makes sense to knock the boost back as i dont want to go an blow my engine when it goes an makes 1.6 bar.

I really am getting confused on this now. For example if my car made 300bhp on 18psi (all turbo) and made 250 on 16psi (all turbo) whats the point in knocking the boost back to 16psi to run a 50 shot of nitrous to at most make 325bhp.

Am i right in thinking that as long as detonation dosnt happen and the right AFR is maintained then it dosnt matter what boost the car makes. I was under the impression that a wet kit mixed nitrous and fuel to keep the AFR even.

Have i got the wrong end of the stick. My brain is fired - revising for finals and now trying to understand this
 

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Discussion Starter · #57 ·
from sallystrothers
You are going to need a hell of an ingntion amplifier to run high boost (above 15psi) and a good size nitrous shot. If you don't have an ignition amplifier then you will have LOTS of misfires. Now are misfires all that bad? YES THEY ARE BAD especially when running a wet shot. A misfire can result if fuel pooling in the intake manifold/ head runners. This then will ignite and explode up through your intake tract (T-vis plates, throttle body, and turbine). This is known as "nitrous backfire" and can blow up a turbo, sending turbine fragments into your engine. I have had this occur once on my car and I luckily did not break anything.

Now all a progressive controller is good for is traction control. It has nothing to do with keeping the engine safer and definitely will not replace a timing retard. People think they can just slap on nitrous and go, that is why so many people blow engines with nitrous. Would you slap on a turbo upgrade and call it good? Certainly not. You would have it tuned to ensure safe operating conditions.

If your intake charge is cooled down more (better intercooling), then boost pressure actually goes DOWN. By lowering the temperature you are lowering the pressure. But this is not how nitrous increases boost pressure. What happens is... nitrous enters the combustion chamber as 1 molecule (N2O). It leaves as many molecules (N2, O2, CO2, CO, NO, NO2, NH3). So you have an extremely high amount of exhaust generated for the amount of intake pulled in. All of this exhaust can't easily flow through the stock wastegate. So it finds its way around through the turbine. So in effect you are cramming all this exhaust through the turbine and the wastegate can't respond in time. So you have a boost spike usually amounting to 1-3 psi. This phenomenon can be averted by using an external wastegate.

It is almost impossible to maintain an operable AFR while on the bottle. ESPECIALLY with a wet kit. All kinds of things are happening. You have an instantaneous fuel pressure drop from the increased flow in the nitrous fuel lines. The jets are only recommended for a certain fuel amount. Dyno tuning must be done to attain the jets that yield the proper AFR. And unreacted nitrous throws off an oxygen sensor.

My own opinion is that nitrous is only good for 2 things: spooling up a turbo and making up for top end hp losses. In the case of the stock CT26 you can boost high, and when the turbo chokes the nitrous can kick in to keep the power level up. So you will be running your 300 bhp at 4000 RPM for example, but then at 6000 RPM you are only making 260 bhp. That is where the nitrous will make up for the hp loss. So what I am saying is you don't want to overlap the nitrous with the turbo's peak power range.

God damn I need friggin cliffs notes for this post.
 

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Discussion Starter · #58 ·
from verc
so then....as the turbo fails to keep up the airflow into the intake charge, the nitrous is being injected into the intake charge...o I see...hmm

so at high rpm's if you decide to jet nitrous to make up for the choking turbo, how will the additional nitrous affect the turbo?

I'm confused, will the additional exhaust damage the turbo that is already at its flow limits?

And won't that run ultra, ultra lean?

Sorry for the ignorance, thanks for the wisdom,
Ambert
 

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Discussion Starter · #59 ·
from bean
in my case with my old ct26 (stock) the n2o did not make a difference,it still fell on it's face at 5500
 

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Discussion Starter · #60 ·
from sallystrothers
When referring to "the turbo choked" I am talking about the volumetric efficiency decreasing. So by adding the "Oxygen rich" intake charge found with nitrous, the engine will be seeing more oxygen in the cylinder, even though the VE is decreasing. So the additional exhaust will not damage anything but simply lower the VE.
 
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