I tried Accel in my Harley, over and over, different heat ranges... IMO, they are junk. others may have had good results, but I never did, and talking to others that tried them in Harleys all had the same opinion... They didn't even work very well, N/A... always fouled out pretty quickly... What finally worked for my set-up was Autolite...
Robert

 

I think he wants good sprayed plugs to see what we are really talking about. I have lots of plugs from many years, but not to many good for out talks. Most once the intial test pass were used again and run and idled and freeeway and etc. so seeing exactly what were talking about will be difficult for me to come up with a good one. But none the less, i will post up some that can help. Maybe TJ, ATV or Baked have some? That's what I would like to see, a good running plug per different combos?
Robert

 

I still don't think you get what I'm saying....

too much timing with TR7's and a 150 shot is no different than too much timing with 11's and a 300 shot. The 7's are the proper heat range plug for a 150 shot and the 11's are the proper heat range plug for a 300 shot. Therefore the desired timing mark should stay in the same place.

 

[QUOTE=shortdog;12738039]4177 is a projected tip, so I'm assuming you meant 3177. Plug gap at around .035 is ok.[/QU

oh **** ur right...my bad

 

We used to do this back in the late 70s and 80s to get the glowing tip out of the center of the combustion chambers on our nitrous motors. It work well. We started using Autolite AR plugs which worked as well and were more consistant when they came out. The Autolite AR plugs come with a cut back strap already, but I'm sure you are ready know this.

 

i tried a set and do not like them for installation and removal purpose.
the timing mark on them with the nickel coating is insane. looks like you drew a line with a sharpie marker, very nice.
however. the coating makes it difficult to screw into the head if you have awkward header tubes, and the fact that my socket gets stuck on them.
i havent put a mic on the porcelain, but i can guarantee is larger than an NGK.
got to wiggle the socket off around a hot header=no fun.
ngk screws in by hand, and socket comes off very easy.
that makes and breaks a plug for me unless the plug picks up et, it aint worth running, IMO.
n/a i get a lil aggressive with timing.
its worth a few hundreths and prolly a 1/2 mph on my current setup.
i keep th mark towards the threads, just outside the bend.
HOWEVER.... on my previous nitrous setups, i never get in the bend. i want it on the flat. keep the plug cool.
you can lean the motor out and go faster and more safe than you can with kicking a couple degrees of timing to it.
"lean is mean, hot is not."
what all the old guys say anyway. they have seen enough motors blow, so i take the advice.
a buddy of mine just hurt a piston with a hot plug in his motor. the timing was so high, along with the hot plug, the timing mark was way down on the 1st thread of the plug, nowhere on the strap.

 

Ok so Im a little confused here. I will be spraying a 75shot dry to start with, but when I bought my hsw dry plate kit, hsw said the tr6 would be fine. I have not installed the tr6's yet, but Im thinkin I should of bought the bref7's? The car is 95% street driven and will not be sprayed alot, so Im assuming thats why hsw said the tr6's are ok? I don't want to blow S**T up so I am all ears! Oh and sorry op, not trying to hijack!

 

there are thousands that run the tr6 on the bottle, people even recommend it.
i would go with the br6ef if you want to spray it, in my opinion. 7 would be a really safe bet, but i would try the 6 and see how she looks.

 

I understand, trust me. What you choose for your motor does not mean that is what works best for my motor, that's the point I am making? If you have found the location that works best for you, that's great. I stated where my timing mark is also, and it works for me. Your trying to say, the location you have is where it should be for everyone and every size hit? I would go as far as saying it may be a good starting point, but likely is not the end all location for all combos. If that was the case we would not be needing talks like these, right? My timing mark is pulled back more for my 300 shot than it is for my 150 shot, that is where my conservative thinking comes in. On a street/strip motor i am not going for ragged edge max power with my 300 shot and my timing mark is probably pulled back further than yours. Can you now see why some of us may have a tuning method slightly different than yours? Now with a 150 shot on my street/strip set-up i know I can run closer to the ragged edge, because the cylinder pressures are not so bad in comparison, and i will bet you a thousand dollars once you see my picture your going to see that it's probably pretty close to what your running, but still not exact, maybe slightly too much in your opinion. Sometimes it is difficult for the dedicated racers to see other options us daily drivers take?

OK, now on to round two. What is your determining factor for your location. There is more to it than a simple MPH increase. But want to hear your side first.

By the way, I have the exact answer as to why I can run more timing on a 150 shot than you do, and for the others that think mine is to much timing, and still make max power. It is really quite simple, LOL. ATV should know, as we have talked about this before. Think 408 with bone stock LS6 heads... Remember, i have well over 300 passes on my car so have kind of an idea of what works. I could also run more timing with the 300 hit also, with no ill effect like I do with the 150, but choose not too. My back is killing me and I have to go lay down...

I don't think your wrong, and i don't think i am wrong. My next input will clarify.
Robert

 

More than 1 way to tune a nitrous car.

How much timing you can get away with has ALOT to do with valve angle, chamber design and quench.

 

Has br6ef (3177) #6 plugs been out for awhile? I didn't know they existed until recently.

Someone needs to take the tr6s off the list completely, but keep the br6ef listed.

 

Ok Ill order up some br6's and sell the tr6's.

 

robert. im sure you have a vast knowledge of nitrous, but i think you may be misleading the average guy who just has a car and threw a kit on it. you are experienced, and know what and what not works. a member sees your post and is like, "i can run more timing, robert does it." then all these posts pop up about pops and backfires, cracked pistons, where did my exhaust valve go, killed my plugs etc.
no way saying you are wrong, but its good for the average guy to start conservative and self teach.

 

Robert, The biggest factor that helped me decide where a good "safe" place was for the timing mark to be was talking with more of the serious guys that have been at it for 30+ years. Other things that influenced my decision were past experiences that I have had. I used to get on this site and trust what others said and it bit me in the *** more than once. That gets to be very frustrating, not to mention expensive. I finally bit the bullet and started looking for more experienced, more serious racers to try to learn from. It was like a whole new world of information about nitrous. I read for hours and hours and hours and then took what I had read and starting putting the new found info to use on my own car. I stopped melting plugs, I stopped having backfires, I actually felt confident making changes to my setup, and I went faster than ever!

My car is pretty much a dedicated race car but my car isn't the only nitrous car that I tune....

In my opinion the timing mark being past the bend on a 150 shot with a 7 is no different than the timing mark being past the bend on a 300 shot with an 11 in it. I understand completely that the cylinder pressures are higher with the 300 shot and it is going to build more heat but that is one of the reasons for the colder plug. It is also my opinion that if the timing mark is getting close to the threads then I am getting close to nipping a plug.

I would rather just step up the jet size than throw more timing at the smaller jet and push it to go faster. If I were in a class that limited my jet size then I'm sure I would push the setup harder but unless that is the case, I see no reason to run the timing that high.

If you don't mind me asking, how much timing are you running with your 300 shot Robert? Also, what plugs and gas.

 

Exactly! I am running bone-stock LS6 heads on a big ole 408. Even though these heads only needed 24° of total timing to make max power on the LS6, compared to the ls1 heads that needed 27/28°, they are not that efficient on my 408. What does this really mean to the LSx? Under normal conditions the LSx likes more timing pulled, or should we say it needs less over all timing on spray or n/a to make max power. So if and when I put some good race heads on the 408 I will likely be moving my timing south for the winter.

Still, the point overall is this, the LSx due to the great Volumetric Efficiency (VE) from the get go, needs less over all timing n/a to get max power compared to motors of past. Hell, some of the cars over at Yellowbullet are starting with 40° timing n/a, and even after pulling for the spray it seems like an ungodly amount to run on the spray (think low VE). However, they are doing fine. It has to do with the heads they are running, like ATV stated.

Here's something interesting that will get the point across on how great, or Volumetric Efficient these motors are. If we look at recent history we will see that injector sizing has been using .5 as the standard multiplier for Brake Specific Fuel Consumption math, for non boosted cars. Well, if you use the math I have in my write up using the standard equation with this ratio, it's good for most motors, but not the LSx. This first came to light when guys had started telling me my math was way to conservative, and the injectors were being sized to large. I thought oh well, the BSFC math I use (my formula is a variation of the standard just simplified) has been the standard for 30 years that I know of. I got to thinking about this. A fully built race motor runs a BSFC of .450, or close, for many years, and some dipping even lower now. So I decided to see what the GM engineers were using to size the LS6 injectors, which are 28lb'ers. the math shows that they used the .450 to size, and the math works out exactly. The first production motor to have a BSFC of .450 on the planet. GM got these motors right, from the get go and they are getting better and better.

Now some of you are wondering why we need to pull timing at all on the spray and why the LSx needs more, or likes more pulled than other motors. When we are spraying it speeds up the flame front so fast that we are actually lighting the power stroke when the piston is still moving upwards on the compression stroke. Think of it this way, the piston is moving upwards and the cylinder ignites prematurely, so now we have the power being made fighting an upwards traveling piston (pre-ignition that leads to detonation). It should light right at the top when it's time for the piston to go down on the power stroke, rather than upwards traveling. Then again due to how good the heads are on the LSx this happens even quicker and deeper into the compression stroke so pulling timing is what brings things back to a normal sequence, or re-times things correctly, and we need more pulled than most other motors due to a better VE. More timing needs pulled the bigger you go to get things re-timed for a sprayed motor as it gets worse as more nitrous gets to the cylinder.

VE is a measurement to determine how well any air pump is pumping. We shoot for 100%, but due to friction, that is not going to happen on an internal combustion engine. Maybe low 90% area is doable? or it may be stuck in the 80s? Production motors, IIRC, are like 60/70% efficient? However, it does relate directly with a BSFC measurement.

Hopefully this makes some sense. I know I go off on a tangent sometimes but believe this all to be related. If something doesn't make sense let me know as I can go into better detail on any point and often have a 1000 things popping into my head at once so it may seem jumbled a bit, LOL. If I am boring you guys you can tell me that too.
Robert

 

I respect and trust all that you have presented as correct insight. However, I come more from a street/strip angle and the tuning in that regard is a little different and hopefully the above post helps my point of view. That's all. I think the majority of guys are going to see that neither one of us are totally right or wrong. They are going to have to figure out what works for them. Start small, check tune, and work your way up is the best advice we can give. You know how I am, if I thought you were giving bogus input I would have been an azz, LOL, byt now.

I listen to the same guys, however, most of those telling the secrets don't have as much time and experience as I do. My first kit was on a 56 Chevy in 1976, IIRC, and there was no one to ask, no dynos, no books, and only basic kits, no safety stuff or knowledge at all. The first motor I ever hurt was my LS6, you'll like this, due to too much timing. So I was one of the first to learn 1st hand how we need to pull timing and gobs of it when going big on the LSx. I also had the 1st LSx, a '97 and had a dry kit on that when everyone was telling me I would blow it up, never hurt it, but didn't go big either.

Anyway, I am not trying to make it out like I am the only one whom knows anything, but rather just sharing my experiences, like you. Your in the top 10 knowledgeable guys on here. ATV and Shiz, are two others that have independently come to the same conclusions I have about the LSx. Things I talk about are things I have done or are doing. Sometimes I get corrected, and that is always welcome. You made me think twice about what I rec for timing, and surely will be more conservative in my suggestions in the future. Like you said, better safe than sorry.

By the way, the last time out with the 408 I ran 14° of total timing with the 300 shot in dual stage. I would pull even more should I put the entire 300 in at once down low... I do know of one whom is running Zero degrees with a dry shot and a LSx. Now if I had your heads on my motor would 14° be good, likely not.
Robert

 

Hopefully that doesn't happen, thanks. That is why this forum is so bad azz, guys like you and others will say what needs to be said. That is normally my policy, start small, check tune, and work your way up. I have always stated that the LSx needs and wants more timing pulled than most other cars. But guess i was a little lax at getting that point across here? But with the caution the three of you have presented maybe all is not lost and someone can still glean the correct information out of it all?

Here's something that has been bothering me for some time. All of the nitrous vendors that are here currently and in the past, have stated no timing pull is needed if stock timing is still stock and a hit of 150 or lower. It's kind of true. However, if one takes a magnified light and really looks at the plug, often times there is the aluminum transfer from the piston, like the picture above (detonation, ask me how I know, LOL). Short term, no problem, long term problem potential. that thinking comes from past thinking of cars that are very low VE. IMO, the LSx will run better if we pull timing on any amount to get the internal timing correct. I have been wanting to call BS on this, and other blanket nitrous tuning statement, like A/F ratio and plugs and... but am not going into all that now, LOL. Maybe we can use this thread to wake everyone up on the need to be conservative with our timing when spraying?

Man this is great, remove one or two guys that cause problems and we can have a really good, meaningful nitrous talk. I know I am enjoying the hell of it.
Robert

 

I'm starting to understand your reasoning for running the amounts of timing that you do, although I still don't agree with you 100% on it I at least understand your theory behind it.

Like ATV said, there is more than one way to skin a nitrous cat....

I like your write up on VE, I think it will help some others on here understand things a little better.

There is one issue that I couldn't agree more with you on... The sponsors. I better keep my mouth shut or I will likely disappear LOL. I do have a funny pic I'd like to share if I can dig it up though.

 

I read an article in a magazine actually about jeff prock and them doing a question and answer. It was an awesome article about nitrous, I wish I could find it online to show all the newbs what we are talking about. If you can find it, find the winter 2009 of "engine masters", a surprisingly good magazine with great info. It address timing, rich tuneups, nitrogen assisted setups, and many more facts that everybody should know coming fron jeff prock we all know it is the CORRECT info.

 

https://ls1tech.com/forums/generatio...ap-please.html

Can someone help me out here? They are recommending a tr-6 for a h/c 150 shot 6.0