Why No Nitrous?

[Dr.Evil]

Just wondering why not many people have NO2 on the R/T? I'm finishing up a Zex install in mine today. I'm also hooking the Alky injection back up. I figure the nitrous and alky will work nicely together. I will only have the 35HP pills in it for starters to see what the A/F looks like. Right now with 100oct and 18-20PSI Im richer than 10:1, so its getting plenty of fuel. Just courious to hear why no one else has the zex kit on their R/T? I've used it on other cars, but they have all been N/A. I figure I'll be plenty safe with using it with the Alky and high octane gas. I'm hoping to break the 300WHP mark on a stock turbo, which to my understanding has never been done.

[RJ138]

Just wondering why not many people have NO2 on the R/T? I'm finishing up a Zex install in mine today. I'm also hooking the Alky injection back up. I figure the nitrous and alky will work nicely together. I will only have the 35HP pills in it for starters to see what the A/F looks like. Right now with 100oct and 18-20PSI Im richer than 10:1, so its getting plenty of fuel. Just courious to hear why no one else has the zex kit on their R/T? I've used it on other cars, but they have all been N/A. I figure I'll be plenty safe with using it with the Alky and high octane gas. I'm hoping to break the 300WHP mark on a stock turbo, which to my understanding has never been done.


I "sort of" have a kit installed on my R/T, it's a NOS system. I was planning on spraying the hell out of the car with the stock turbo but wanted to get some dyno tuning first. But I have been too busy and the car was demoted to my daily driver so the last thing I need to do is blow it up.:o I will probably finish installing it once I get a house, I have a bunch of safety stuff for it plus wideband activation and other goodies. I was going to start at 35hp also and work my way up, I have jets from 35 to 150 hp.:D

If I remember correctly Larry made a hair over 300hp on the stock turbo and no nitrous. I believe the wastegate line was disconected.;) This had to be at least 3 or 4 years ago.

[zin]

I think the main reason is that there just aren't that many of these cars out there! But, it seems that there will be at least 3 of them that have nitrous as I plan on putting some on mine too. I'll be doing it a bit differently though, since my RT has just about everything done to it already (T3/T4, FMIC, Injectors, 255, bla bla bla), I'll just be using it to make up for the lack of boost at the lower RPMs. I'll also be doing a dry system (nitrous in the air intake, fuel via the injectors) which is a little uncommon in turbo car due to the fact they cause a variation in the fuel pressure as boost comes up, but since I'll be cutting the system out once the boost goes past 5-6 PSI, it won't be an issue. The main thing to keep in mind, don't exceed the strength of the engine with the total amount to HP generated. That's why I'm not doing full time nitrous, I'm already over 300HP with the turbo, etc, if I add anything more I'll likely break it, so I'll just use the nitrous to fill in the torque curve a bit till the turbo takes over.

[Dr.Evil]

I think the main reason is that there just aren't that many of these cars out there! But, it seems that there will be at least 3 of them that have nitrous as I plan on putting some on mine too. I'll be doing it a bit differently though, since my RT has just about everything done to it already (T3/T4, FMIC, Injectors, 255, bla bla bla), I'll just be using it to make up for the lack of boost at the lower RPMs. I'll also be doing a dry system (nitrous in the air intake, fuel via the injectors) which is a little uncommon in turbo car due to the fact they cause a variation in the fuel pressure as boost comes up, but since I'll be cutting the system out once the boost goes past 5-6 PSI, it won't be an issue. The main thing to keep in mind, don't exceed the strength of the engine with the total amount to HP generated. That's why I'm not doing full time nitrous, I'm already over 300HP with the turbo, etc, if I add anything more I'll likely break it, so I'll just use the nitrous to fill in the torque curve a bit till the turbo takes over.

You have me worried now about using a dry system on this car with the fuel pressure issue...I'll get it all in there and do a quick pull with and without the alky on the 35hp jets and see what the AF looks like. If it looks good then I won't worry about it. If it goes instantly lean I'll pull it off and install a wet system.

BTW I thought N2O low in the RPM range is a bad idea? Something about nasty intake backfires?

[zin]

You have me worried now about using a dry system on this car with the fuel pressure issue...I'll get it all in there and do a quick pull with and without the alky on the 35hp jets and see what the AF looks like. If it looks good then I won't worry about it. If it goes instantly lean I'll pull it off and install a wet system.

BTW I thought N2O low in the RPM range is a bad idea? Something about nasty intake backfires?

It's more to do with excessive cylinder pressure, though back-fires can happen, but is more common with the "wet" system, due to the poor fuel distribution leaning out a cylinder, then BANG, back fire just as you would expect from a lean cylinder.

As for running a dry system with a turbo, it's only a problem if you are a manufacture of kits, mostly because turbo cars are too easy to turn up the boost, if they had to keep the boost stock, it wouldn't really be a problem because you would know that you would alway be able to bump the fuel pressure to a specific level and have the fuel that you expect. The reality is that no one keeps the boost stock!:eyebrows: So, you never know how much fuel you'll have to work with. It won't even factor in for me because it'll be off before I'm making any real boost, so it's pretty much the same as if it were on a NA engine.

If you plan on running a dry kit (boosting the fuel pressure to get the fuel for the nitrous system), then you have to figure you'll be a bit rich before the boost comes up. These systems work by sending an artificial boost signal to the FPR, telling it to raise the pressure by 25-30PSI over static (no boost, no vacuum), that's about as much as you can count on from a good fuel pump and is about the max opening pressure of most fuel injectors (80-85PSI gauge). The problem comes in because you have to count boost, each PSI of boost takes away a PSI of "extra" fuel for the nitrous system, so you can start running out of fuel pretty fast as the boost comes up. In my case I'll see as much as 25PSI, that's almost all the "extra" fuel pressure a dry kit is made to add, so if I tried to run it like it would be on a NA car(all the time), I'd be ok until the boost came on, then I'd have almost no extra fuel!, and in all likelihood, 4 new ashtrays!:banghead: And since I don't smoke, that'd be pretty useless! If you don't run too much boost, then, like I mentioned above, you'll be rich at first, the it'll lean it's self out as the boost come up. Though "wet" systems suffer from poor fuel distribution, they are much simpler to deal with on turbo cars, in either case, we have to take care to not get too greedy (an easy thing to do). As an aside, a "wet" kit's tendency to have problems goes up exponentially as it's HP level goes up, in short, you're very unlikely to have a problem with a small hit (35HP), but very likely with a large hit (150HP). Also, those HP number will be a bit low as they are rated on NA engines so the added intercooling effect and quicker spool (and sometimes added boost pressure) are not factored in, so you might be surprised at what a "small" hit will do for you!:eyebrows:

BTW, if you normally run the alky, keep it on when you run the nitrous, it provides some anti-detonation protection and you don't want to handicap yourself in that regard.

Mike

[86Shelby]

One reason I can think of right off the bat is there is no way to easy retard your timing a little bit to run the juice. That and Nitrous simply isn't very popular in this crowd. I'd like to dabble in it when the time comes that I don't have to worry about getting my butt to work if I accidentally melt something down.

[GLHSKEN]

When you can make 300 whp without it, why add the complexity. Just a thought..

[2.216VTurbo]

It's more to do with excessive cylinder pressure, though back-fires can happen, but is more common with the "wet" system, due to the poor fuel distribution leaning out a cylinder, then BANG, back fire just as you would expect from a lean cylinder.

As for running a dry system with a turbo, it's only a problem if you are a manufacture of kits, mostly because turbo cars are too easy to turn up the boost, if they had to keep the boost stock, it wouldn't really be a problem because you would know that you would alway be able to bump the fuel pressure to a specific level and have the fuel that you expect. The reality is that no one keeps the boost stock!:eyebrows: So, you never know how much fuel you'll have to work with. It won't even factor in for me because it'll be off before I'm making any real boost, so it's pretty much the same as if it were on a NA engine.

If you plan on running a dry kit (boosting the fuel pressure to get the fuel for the nitrous system), then you have to figure you'll be a bit rich before the boost comes up. These systems work by sending an artificial boost signal to the FPR, telling it to raise the pressure by 25-30PSI over static (no boost, no vacuum), that's about as much as you can count on from a good fuel pump and is about the max opening pressure of most fuel injectors (80-85PSI gauge). The problem comes in because you have to count boost, each PSI of boost takes away a PSI of "extra" fuel for the nitrous system, so you can start running out of fuel pretty fast as the boost comes up. In my case I'll see as much as 25PSI, that's almost all the "extra" fuel pressure a dry kit is made to add, so if I tried to run it like it would be on a NA car(all the time), I'd be ok until the boost came on, then I'd have almost no extra fuel!, and in all likelihood, 4 new ashtrays!:banghead: And since I don't smoke, that'd be pretty useless! If you don't run too much boost, then, like I mentioned above, you'll be rich at first, the it'll lean it's self out as the boost come up. Though "wet" systems suffer from poor fuel distribution, they are much simpler to deal with on turbo cars, in either case, we have to take care to not get too greedy (an easy thing to do). As an aside, a "wet" kit's tendency to have problems goes up exponentially as it's HP level goes up, in short, you're very unlikely to have a problem with a small hit (35HP), but very likely with a large hit (150HP). Also, those HP number will be a bit low as they are rated on NA engines so the added intercooling effect and quicker spool (and sometimes added boost pressure) are not factored in, so you might be surprised at what a "small" hit will do for you!:eyebrows:

BTW, if you normally run the alky, keep it on when you run the nitrous, it provides some anti-detonation protection and you don't want to handicap yourself in that regard.

Mike

Aw C'mon Mike, do go acting like you know all about Nitrous systems:lol: :peace:


















BTW, how many years have you been running NitrousSupply.com again:D ?

[turbovanman²]

One reason I can think of right off the bat is there is no way to easy retard your timing a little bit to run the juice. That and Nitrous simply isn't very popular in this crowd. I'd like to dabble in it when the time comes that I don't have to worry about getting my butt to work if I accidentally melt something down.

And they do have alot of timing.


When you can make 300 whp without it, why add the complexity. Just a thought..

That, the fact you need to fill a bottle, etc. I am a boost guy all the way, :amen:

[WVRampage]

I have had wet NOS kit on my TII for about 4 years now,It doesnt get used much but it is good for a solid 30 hp at the wheels.I will be removing the nitrous and going with a alky kit in the future im sure.

[Dr.Evil]

I have had wet NOS kit on my TII for about 4 years now,It doesnt get used much but it is good for a solid 30 hp at the wheels.I will be removing the nitrous and going with a alky kit in the future im sure.


I have an alky kit on my car now, and it doesn't really help at all. Its already running pretty rich without it, and the alky doesn't help. I'm sure a progressive system would help the cause but I have it set up to only come on after 15PSI. I was hoping the nitrous mixed with the alky would help get the A/F to around 12/1, right now its richer than 10/1.

Zen you got me worried about using it at higher boost levels. I didn't know thats how the FPR worked with a turbo car. So at say 20PSI boost and the nitrous, Id only be getting 5psi more fuel pressure? I was thinking the alcohol would act as an extra fuel source and this wouldn't be a major problem? I would only be running 100 octane with the nitrous/alky combo. But yea I don't really want to tear into the motor just for a 30HP bonus that went wrong ha

I'll turn the boost down and try it like that. If it looks good at low boost, ill slowly turn it up until the A/F looks good.

Or maybe I'll just pull it off and sell it before I break something.

[turbovanman²]

Our regs are 1:1, so 20 lbs of boost equals 20 more psi of fuel pressure.

[zin]

Aw C'mon Mike, do go acting like you know all about Nitrous systems:lol: :peace:


BTW, how many years have you been running NitrousSupply.com again:D ?

It all started on April Fools Day in 1994, been the longest practical joke in history!:lol: But it was NOS then, Nitrous Supply just started in 03. :thumb:

[zin]

One reason I can think of right off the bat is there is no way to easy retard your timing a little bit to run the juice. That and Nitrous simply isn't very popular in this crowd. I'd like to dabble in it when the time comes that I don't have to worry about getting my butt to work if I accidentally melt something down.

Well, there is an easy way to retard your timing, just adjust the distributor, the down. :D Of course that means driving around with less timing all the time, but it is an easy and effective way to retard the timing. Also, if you are running a stock cal, the timing will be fairly conservative, car makers don't want to replace an engine just cause you got some bad gas! If you are running an aggressive tune-up, yeah, you'll have to do something to get some timing out, but you only need to take about 2* per 50HP of nitrous added, so that's not too hard to live with, even if you have to do it via the dist.

Nitrous isn't for every occasion, it's perfect for those that need some extra power sometimes, but are pretty happy with the HP the engine is making most of the time. It's still the best deal in a HP per $$ sense. But if you need continuous HP (like towing, etc), it's not the ticket.

Doh! got some customers now, gotta go.

Mike

[turbovanman²]

Well, there is an easy way to retard your timing, just adjust the distributor, the down. :D Of course that means driving around with less timing all the time, but it is an easy and effective way to retard the timing. Also, if you are running a stock cal, the timing will be fairly conservative, car makers don't want to replace an engine just cause you got some bad gas! If you are running an aggressive tune-up, yeah, you'll have to do something to get some timing out, but you only need to take about 2* per 50HP of nitrous added, so that's not too hard to live with, even if you have to do it via the dist.

Nitrous isn't for every occasion, it's perfect for those that need some extra power sometimes, but are pretty happy with the HP the engine is making most of the time. It's still the best deal in a HP per $$ sense. But if you need continuous HP (like towing, etc), it's not the ticket.

Doh! got some customers now, gotta go.

Mike

Well, you do know the TIII has no distributor! right? :confused: :rolleyes:

[zin]

Well, you do know the TIII has no distributor! right? :confused: :rolleyes:

Sorry, talking in general terms, I've only recently broke my 16V cherry! :lol: I'm used to talking about 8v stuff so that's where my head was.

Even still, if the timing is ok for big boost, it would be ok with "normal" boost and a small shot of nitrous, like I mentioned earlier, for a 50HP hit you'd only really need 2* out, and that is from the point of optimum timing. I guess this would be a good time to talk about why timing is even adjusted at all with nitrous. Its pretty simple really, because nitrous has about 14% more oxygen than normal air, it will speed up the burn rate. Under normal circumstances we'd like to time our engines to make peak cylinder around 15-20* ATDC, most of the time that means starting ignition at about 36* BTDC. If you speed up the burn rate, and don't retard the timing, peak cylinder pressure will occur closer to TDC and away from the "sweet spot" of 15-20* ATD, the danger there is that not only do we loose HP, but the pressure rise can induce detonation, the quickest way to kill any engine! On stock tunes (at least) the timing is generally much less than optimum, that's how alot of chip makers are able to make some extra HP on their NA tunes and would have to be removed (or have an alternate way of reducing timing when the nitrous came on). Of course if you are doing your own programing, you can leave a few degrees out, or have a switch program. Bottom line is if you know what is going on, you can be safe. Hope that all made sense to everyone. :D

Mike

[turbovanman²]

The thing is the TIII has alot of timing, so Nitrous could be a bad thing when getting on it, :o

[zin]

The thing is the TIII has alot of timing, so Nitrous could be a bad thing when getting on it, :o

Well, I am a little new to the nuances of the TIII, so I'll say it's better to be safe than sorry. When you say it has a lot of timing, how much is a lot? And are we talking total timing or base? I find it a bit odd that a 4-valve engine would need to have much timing, most of my experience with them has been that they are so much more efficient than a 2 valve that they don't need/want much timing. I alway recall the Cosworth 4cyl sprint car engines that would make best power with the timing locked out at 24* total, that's alot less than your typical 2 valve engine!, of course that is a Cosworth engine, they tend to be exceptional!

Mike

[turbovanman²]

Well, I am a little new to the nuances of the TIII, so I'll say it's better to be safe than sorry. When you say it has a lot of timing, how much is a lot? And are we talking total timing or base? I find it a bit odd that a 4-valve engine would need to have much timing, most of my experience with them has been that they are so much more efficient than a 2 valve that they don't need/want much timing. I alway recall the Cosworth 4cyl sprint car engines that would make best power with the timing locked out at 24* total, that's alot less than your typical 2 valve engine!, of course that is a Cosworth engine, they tend to be exceptional!

Mike


Not sure, contact ShelGame but he's suprised how much there is and there known for it. I don't know why they did it but it worked, they make great power, :hail:

[cordes]

I believe that there are some 3D graphs of the timing for the TIII out there. Stock they were aggressive to say the least. I don't think you could add any more without problems. Of course the injector DC is about maxed on them stock too, so they were certainly going for all out performance with that cal right from the factory.

[zin]

I believe that there are some 3D graphs of the timing for the TIII out there. Stock they were aggressive to say the least. I don't think you could add any more without problems. Of course the injector DC is about maxed on them stock too, so they were certainly going for all out performance with that cal right from the factory.

Now that you mention it, I do recall something about the cals being 3-D where all the others were 2-D, which was causing the disassemblies to take alot longer. I don't recall what the amount of lead was as I wasn't anticipating working with a TIII. I'll try looking it up on D-cal before I pester anyone else.:nod:

Mike

[cordes]

Now that you mention it, I do recall something about the cals being 3-D where all the others were 2-D, which was causing the disassemblies to take alot longer. I don't recall what the amount of lead was as I wasn't anticipating working with a TIII. I'll try looking it up on D-cal before I pester anyone else.:nod:

Mike

I believe that Shelgame is working on some TIII cals that will be coming out soon. It won't be long before there will be some very serious TIII cars being tuned by their owners which should up the ante for TIII performance in a huge way. :nod:

[turbovanman²]

I believe that Shelgame is working on some TIII cals that will be coming out soon. It won't be long before there will be some very serious TIII cars being tuned by their owners which should up the ante for TIII performance in a huge way. :nod:

Yeah, he's trying to make me a SMEC copy TIII cal with some tweaks for the van, :nod:

[RJ138]

I would love a custom cal, is it really hard to get into making your own cals? I should have 2 R/Ts over 350whp pretty soon here and being able to make my own tweaks would be awesome.

I do have a trimcal but the adjustments are very limited, the car with the Trimcal is the car that will have nitrous (can adjust spark). Well at least that was the plan.

[cordes]

I would love a custom cal, is it really hard to get into making your own cals? I should have 2 R/Ts over 350whp pretty soon here and being able to make my own tweaks would be awesome.

I do have a trimcal but the adjustments are very limited, the car with the Trimcal is the car that will have nitrous (can adjust spark). Well at least that was the plan.

If you have a good dissassembly, it is super easy. If you go over to www.moparchem.com you will see a ton of info posted up about it. Unfortunately the support for publicly available TIII cals is very limited right now, so that might not be the easiest for you to do. The cals that Rob is working on should hopefully change that though.

[zin]

If you have a good dissassembly, it is super easy. If you go over to www.moparchem.com you will see a ton of info posted up about it. Unfortunately the support for publicly available TIII cals is very limited right now, so that might not be the easiest for you to do. The cals that Rob is working on should hopefully change that though.

Although its a little off-topic, I was wondering if the SBECs for the TIII are the same as other turbo SMECs, other than the program? My hope is to be able to program any Turbo SBEC to run a TIII. I guess I should post this in the ECU section....

Mike

[Dr.Evil]

Put the 30HP shot in and tried it at the track today. A/F looked nice fine (10:1 or richer) and it felt good. Was kinda worried about the EGT as I don't have a guage for that, but I only used it at the top end so I don't think it had time to get too hot. Car ran great today, unfortunatly no times at the track I was at. I would say mid/low 13's easy. I plan on taking it to sacrament soon and get some real times. Trying to dip into the 12's w/ the stock turbo. If not a t3/t4 50 trim is in order :D

[BIGBRUDDA]

Laughing gas is for drug addicts!!:D

[RJ138]

Put the 30HP shot in and tried it at the track today. A/F looked nice fine (10:1 or richer) and it felt good. Was kinda worried about the EGT as I don't have a guage for that, but I only used it at the top end so I don't think it had time to get too hot. Car ran great today, unfortunatly no times at the track I was at. I would say mid/low 13's easy. I plan on taking it to sacrament soon and get some real times. Trying to dip into the 12's w/ the stock turbo. If not a t3/t4 50 trim is in order :D

Do you have it so rich because of the EGTs? 10:1 or less seems really rich to me.:confused2:

[zin]

Do you have it so rich because of the EGTs? 10:1 or less seems really rich to me.:confused2:

While I'll agree that 10:1 and less is a bit much, it isn't uncommon to see 10.5-11:1 A/F on turbo/supercharged/nitrous engines, at least when they are running high HP. Alot of the fuel is being used to cool the charge and stave off detonation. There generally is more power to be had in a leaner mixture, but that little bit of power isn't normally worth the risk. Like they say, "lean is mean, but fat is happy!".:thumb:

[Dr.Evil]

While I'll agree that 10:1 and less is a bit much, it isn't uncommon to see 10.5-11:1 A/F on turbo/supercharged/nitrous engines, at least when they are running high HP. Alot of the fuel is being used to cool the charge and stave off detonation. There generally is more power to be had in a leaner mixture, but that little bit of power isn't normally worth the risk. Like they say, "lean is mean, but fat is happy!".:thumb:

Yea I'm not worried with the AF. Id like to get it a little leaner, but don't want to risk buring something up.

This is how it is with the Stage 3 cal/+40s. I don't have an AFPR, just the stocker.

I was having fun picking on the SRT4 guys with more $ in their intercoolers and tuning than I have in my entire car. :lol:

[Ondonti]

nitrous works great when you are working on your powerband or you are at the limit of your boost for whatever octane level.

Doesnt make much sense to start spraying if you dont need a wider powerband or if you are not maxing out your turbo or octane level though.

[bansheenut420]

I believe that Shelgame is working on some TIII cals that will be coming out soon. It won't be long before there will be some very serious TIII cars being tuned by their owners which should up the ante for TIII performance in a huge way. :nod:

Oh really!? :D Any more info on these? You have no idea how nice that would be. I am just a little nervous about putting my holset on because of this problem..... And my exhaust guy wont quit messing with his supra to make my downpipe. :(

[Dr.Evil]

stock turbo runs out of steam at the end of the track, the N2O helps with that. Also I don't have the best intercooler in the world so I have alky injection on it, mixed with the n2o it runs very well.

I know everyone says boost is better but I like to be different (thats why I drive an R/T in the first place) so I like experimenting with other ways of making power. Why have just boost when you can add boost + n2o or alky and go even faster? Its really safe if tuned/installed correctly and you monitor the A/Fs and EGT's.

[turbovanman²]

Yeah, nitrous and boost go together like peanut butter and jam, ebert and roper, sonny and cher-:wow1::clap: