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Starting line crowd

mike

Nitro Member
#21
Heard a story about someone taking a zeus button in the calf. Imagine getting shot in the lower leg.
We have slow-mo video of a run last year where we lost a zues button from starting line shake and after the tire ran over it, you see the button fire across over our heads like a bullet.
Heard a story about someone taking a zeus button in the calf. Imagine getting shot in the lower leg.
We have slow-mo video of a run last year where we lost a zues button from starting line shake and after the tire ran over it, you see the button fire across over our heads like a bullet.
That someone that took in the leg with a Dzus button was Will Hanna- watched him drop like a bowling pin-he even had a spin to him
 
#23
Self Disclosure: Over the past 10-15 years or so, I have personally "snuck" down to the starting line at least 3 or 4 times at a national event while the nitro cars were running. I don't condone this at all. I assume NHRA has tightened up security over the years, but I will say, it was easy to do, nobody ever questioned me. I guess you'd say I have somewhat of a "knack" for looking like I belong in certain situations. Blending in with a crowd, acting more important than I am.... which again - I don't recommend TO ANYONE. It's a good way to get hurt or beat up. The starting line area is very fast paced, lots of moving vehicles and people. I'm sure the NHRA security people know who the regular crew people are week in and week out; it's like a traveling family. So when some idiot like me, tries to interject themself into that group - it's a recipe for disaster, I'm telling you. Can you imagine if something really bad did happen, to say a person like me up there.... and NHRA had no idea who I was; the race teams didn't have any idea who I was??? Just NOT GOOD. Maybe the race personell wear ID passes now; often times in the past they didn'tlike to, because of lanyards, badge holders, etc dangling or getting caught up in your clothing or what have you. You could also buy look-alike crew uniforms.... so again, a complete outsider, who knows what they're doing, could easily blend in with a uniformed race pit crew... walk through the lanes, up under the tower, start the car, do the burnout, set the idle/turn the screws, wipe the tires... then step back and watch the cars launch. Turn around and walk away. I'm telling you, I did it so I know.

I guess my point in telling you this is, I hope NHRA has tighter procedures in place. Because not only someone like me, who just wants to be there when 2 nitro cars blast off.....but what if someone was out to do something malicious to a driver, or to intentionally stop a run or damage a race car??? But back to the original topic - - yes, I've seen many cars get squirrly and do strange things wight there behind the waterbox even. It's a dangerous place
 

Jeff

Nitro Member
#24
Several years ago at Tulsa during a divisional, the car in front of us had a screwdriver attachment to a drill fall out right at the start of a run, it was about 3" long and nobody (including me) noticed it. My wife did her burnout and shot the piece through the arch of my shoe and about 1" into my foot. I looked down, almost fainted, then went on about my staging duties .... albeit hopping on the remaining good foot. My wife figured I had burned my calf (again) on the downswept headers and she went ahead made her qualifying pass after giving me a hard time on the radio when I hopped to the front of the car to get her close to the staging beams.

I've been hit by numerous rocks during burnouts. I always look at the ground with a baseball cap on, or turn by back to the car .... it's about the same as getting hit by one riding our Harley's .... similarly, you know the risk when you put yourself in that situation.

Right now, I'm missing about 1/5 of the hair on my left forearm ... during the starting procedure at Belle Rose divisional week before last the car decided to burp and the flame ball from the intake pressure relief manifold headed right for me. It was quick, but the smell of burning hair was unmistakable as I made sure the blowoff reset and restarted the car.

Jeff
 
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Reese

Nitro Member
#25
Right now, I'm missing about 1/5 of the hair on my left forearm ... during the starting procedure at Belle Rose divisional week before last the car decided to burp and the flame ball from the intake pressure relief manifold headed right for me. It was quick, but the smell of burning hair was unmistakable as I made sure the blowoff reset and restarted the car.
Jeff
Oh that 6:21 was a soft setup in Belle Rose, yea right.
It was a pleasure meeting and talking to you, wish work would have not gotten in the way so I could have been back Saturday or Sunday.
 

Jeff

Nitro Member
#27
Oh that 6:21 was a soft setup in Belle Rose, yea right.
It was a pleasure meeting and talking to you, wish work would have not gotten in the way so I could have been back Saturday or Sunday.
Great to put a face with the name Armand! Sorry work kept you away for the weekend. I look forward to catching up with you longer next time.

It's sorta funny that turning the last two stages of nitrous off at the 1/8th is a 6.21, but leaving it on through the 1/4 is only a 6.16 ..... that said I only had 4 degrees of timing in the motor as we wait for Dart to make us another head. Actually, about to walk out to the shop now to increase the 3rd stage size... rather than increase the timing, I'm initially going to increase the nitrous to match the timing.
 
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Cliff

Nitro Member
#28
Jeff, how many stages of nitrous do you use? Just curious. I have heard that some Pro Mods use 3 stages for 1/8 mile, maybe 4, and up to 6 stages for 1/4 mile. Wow.... I love watching T/D and T/S and seeing the nitrous cars mix it up with the blower bunch. Yeah...... :)
 

Jeff

Nitro Member
#29
Right now 3 stages in total. Most of the readers of this thread should skip this post, because I'll be way off topic....

Stage 1 is a 30 jet
Stage 2 is a 34 jet
Stage 3 is a 36 jet (I think)

Right now, all in we are only running 4 degrees of timing with all of the stages turned on, we've had some huge detonation issues that we've (David Nickens and I) have ultimately figured out are a bad head rather than too much timing. The big dogs in Pro Mod are running more stages, and generally even more timing (say 6.5 degrees or more) because they have better heads and go through more pistons in race than I do in a year (well, not last year, but hopefully this year). I am trying to sneak up to good horsepower while bracket racing.....

Nitrous causes the flame front to move very quickly (mineshaft conditions in a bottle) so you have to make the timing much closer to TDC to maximize the thrust applied to the piston. When you run too little timing (e.g. too close to TDC ... or even after TDC.... you are wasting effort ... I think they say you want maximum thrust to be roughly 17 degrees after TDC to accelerate the crank the best .... I'm sure that is very rough and changes with a "slow burn" fuel like nitro verses a "quick burn" fuel like nitrous/gas .... which i think is why alky cars can almost always produce more HP than nitrous ... the power pulse is longer and more efficient/effective).

People ask how much horsepower relative to jet size all the time. Each intake runner has it's own jet/injector for fuel and nitrous for each stage, 2 stages are on the outside of the runner and the 3rd stage is plumbed from the inside down the middle of the intake runner .... a royal pain to change, and something I'll only do in the shop, with all the runners stuffed full of paper towels and nobody asking questions or rushing me ... i feel like a dentist changing those jets. I think the 30 jet the way we run is roughly 250hp initially, and the 36 jet is close to 400hp ... so all in roughly 1,000 hp of nitrous/gas added to roughly 1350hp of 762 cu of V8.

We treat the motor as 8 different engines, timing and fuel (the fuel nitrous jet which starts roughly 4 jet sizes smaller than the nitrous jet) are changed based on what the spark plugs and O2 sensors tell me is going on. A spark plug tells you most of the story (clipping the ignition right at the finish line), but it is a cumulative story of what the plug saw on the run. The O2's tell you each chapter of the story, but just O2's with no spark plugs will have you not knowing if you are reading fiction or non-fiction. We also run EGTs but they pretty much just tell me which rocker arm or valve spring broke so I pull the correct valve cover immediately .... it's not quite that bad, but it's close).

A 30 jet has a .030" diameter, so an area of .015 x .015 x 3.1416 = .000707 cu/in. So a 34 jet is .000908, 28% larger, and a 36 jet is .001018 or 44% larger than the 30. So somebody is gonna ask why a 44% larger hole makes 60% more horsepower ... and at that point I'm going to remind everyone that after one year of engineering school I switched over to accounting so I could make enough money to have engineering hobbies!
 
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Cliff

Nitro Member
#30
Thanks Jeff! Interesting stuff to me. I know just enough about nitrous to ask dumb questions. heh I watch the Pro Mod guys do a really long purge on the starting line, & am told it is to get the system to a certain temperature for maximum performance. Do you do that with your car? I watch the T/D "bottle rockets" & they don't seem to do much of a purge. Guessing this depends on what type of system you have.
 
#31
They do long purges of nitrous to drop pressure due to the heating of the bottle(s). Initally, I didn't know why they blew a ton of nitrous until I researched it to see why they they did it.
 

Jeff

Nitro Member
#33
Thanks Jeff! Interesting stuff to me. I know just enough about nitrous to ask dumb questions. heh I watch the Pro Mod guys do a really long purge on the starting line, & am told it is to get the system to a certain temperature for maximum performance. Do you do that with your car? I watch the T/D "bottle rockets" & they don't seem to do much of a purge. Guessing this depends on what type of system you have.
Pressure and temperature within the bottle directly correlate, but most people reference pressure because the purge itself causes cool areas near the pick up tube inside the bottle that take a while (say 15 seconds) to smooth out (and pressure builds during that period).

The purge has two purposes. One to get bottle(s) pressure down to a starting target ... 945 to 950psi for us. The other is an attempt to get the lines filled with liquid nitrous rather than gas ... but in order to do that you really have to "motor purge", which is something not that many folks do (motor purge is to literally open the gas (not fuel) side of the nitrous system jets and bleed them into the intake). We have found a very accurate system to automate the external purge process for our car, so a switch just gets flipped and it purges to 950 automatically ... if the sun is on the bottles you'll see it purge until the third stage comes on. At the end of the run the bottles are at roughly 840 psi. Ideally we'll only purge about 1 1/2 pounds of nitrous prior to the run, but it depends on whether I've done a good job monitoring the bottle heater in the lanes. After a run, both 10lb bottles need about 4lbs each of nitrous to be full again. Each run uses about $25 of VP C23 fuel and $25 of nitrous.

The top level nitrous pro mod guys all run electronic fuel injection. So they are often delivering all of the gasoline part of the equation through the HUGE injector they run. When you hear about a 5th or 6th system you are probably hearing more about a nitrous only jet that is designed to replace the volume lost by the drop in bottle pressure during the course of a run. In my case, running carbs, our set up gets noticeably richer air/fuel wise from the 1/8th mile to the 1/4 because I don't pull fuel as the bottle feed rate naturally slows. For me the upside of that is that unburnt fuel pulls heat off the top of the piston and helps to decrease detonation (trading MPH for longer lasting pistons/rings).

If I wore anything other than a black T shirt while working on the race car it would get thrown away each day....
 
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Cliff

Nitro Member
#34
Thanks Jeff. One, no 2 last questions. Sometimes when watching PDRA, I see the cars way down in the shut off area, & they are purging the system. Does this need to be done after the run all the time? Do you do it? Last, is it better to run race gas or alky with nitrous?
 

Jeff

Nitro Member
#37
Thanks Jeff. One, no 2 last questions. Sometimes when watching PDRA, I see the cars way down in the shut off area, & they are purging the system. Does this need to be done after the run all the time? Do you do it? Last, is it better to run race gas or alky with nitrous?
After the run, you are going to pull the bottles off, so you are going to eventually bleed the systems off .... but, the nitrous side plunger in the solenoid has got a ton of pressure against the thermo plastic seal and the less time it spends with all of that pressure on it the less likely you are too get nitrous bypassing the seal (which tends to lead to those hair eating burps I mentioned earlier).

Methanol is a great oxygenated fuel, but it does not play well with nitrous. I don't think it burns hot enough to react well (e.g. get the nitrogen and oxygen molecules to separate and give the fuel the oxygen it needs), and being oxygenated already the literal "bang for the buck" is just not there. I've seen a few guys run alcohol carbs and nitrous/gas systems (e.g. having both fuels shoved into the intake in appropriate quantities), but they never seem to stick with it for long.
 

Nunz

Nitro Member
#39
When Larry Miner (Miner Bros) drove my car in 2005 Fred Miner, Larry's brother, was on my crew. We noticed that Fred was missing an eye. He said he lost it because he was standing behind his dad in their blown gas Opel when it kicked a rock up on the back tire and took his eye out on the starting line. The same thing almost happened to me at the 2007 Tucson divisional while we were warming up my car on stands in our pit. I was wearing sun glasses and got a rock off the left rear tire in my eye. 10 minutes later I was in ER at the nearest hospital getting sunglasses dug out of my eye. My exploding sunglasses managed to save my eye from the impact of the rock, thankfully.

I never stand behind a car doing a burnout or launching at any distance in any class and I always wore safety glasses to the starting line and while warming up in the pits after that incident in 2007.


View attachment 4527
Not to derail the thread, but I remember that badass little Opel, such a tiny car it makes the slicks look like they’re 40 inches tall!
 

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