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Discussion Starter #1
I am experimenting with nitrous in my alcohol motor. From what I can tell, the problem with nitrous and alcohol is that due to the cooling effect of alcohol the nitrous doesn't dissociate rapidly enough to make the extra oxygen available early enough to be of much use, hence not as much power is developed.

Would higher compression help? My current motor is 13.7:1 but I can easily go as high as 15.3:1. Any thoughts on this?
 

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Depending on what your overall goal is, you can run gas/N2O in your ally motor. Sometimes it's necessary to do that to put heat back in the chamber.
 

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I ran (small block Chevy gen 1) 12:1 static comp and Methanol and NOS, no problem. Works fine. Motor made 847hp (FAST XFI) on the dyno on gas (just to get a tune-up) switched to alcohol and sprayed it with 3 200 shots at 20degrees total with 14degree heads. At 2700lbs went 4.99 @ 142.5 in the 1/8th, and 7.61 @ 181 1/4............never hurt anything. Calculator says it's making just under 1500hp......:cool:




I am experimenting with nitrous in my alcohol motor. From what I can tell, the problem with nitrous and alcohol is that due to the cooling effect of alcohol the nitrous doesn't dissociate rapidly enough to make the extra oxygen available early enough to be of much use, hence not as much power is developed.

Would higher compression help? My current motor is 13.7:1 but I can easily go as high as 15.3:1. Any thoughts on this?
 

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I am experimenting with nitrous in my alcohol motor. From what I can tell, the problem with nitrous and alcohol is that due to the cooling effect of alcohol the nitrous doesn't dissociate rapidly enough to make the extra oxygen available early enough to be of much use, hence not as much power is developed.

Would higher compression help? My current motor is 13.7:1 but I can easily go as high as 15.3:1. Any thoughts on this?
Details please! I alky injected and spray an 88 pill fuel and nitrous adn have no problems what so ever. Sure you could make some more horsepower with spraying gas, but if you are not looking for everything possible its not worth putting another tank and pump on the car. This is on a 14.5 to 1 565, BB-4x heads.
 

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The times in my sig are with a Ron's Terminator and an NX alky enriched plate, I went back to a gas carb and an IS plate with the same jet both on Q16 and lets just say my sig needs to be updated.........

Anyone that needs a like new NX conv style billet plate wthe alky jets I'll make a smokin deal............
 

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Discussion Starter #6
2150lbs with driver RED 572 conventional head BBC, EFI and an NX plate system. Ran a 74 jet today first time today, went 7.58 @ 180,
 

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What does it run on motor? By the MPH you have there is a bunch left in it. I have only made a few 1/4 mile passes, but i went 7.60 at 176. On the bottle i went 7.25 at 161 clicking the motor at 1000'. i turned the bottle on at .3 and off at 3.8. 4.51 @ 155 in the 1/8 on that pass. Are you adding the extra fuel through the EFI or are you adding extra fuel through the plate?
 

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Discussion Starter #8
What does it run on motor? By the MPH you have there is a bunch left in it. I have only made a few 1/4 mile passes, but i went 7.60 at 176. On the bottle i went 7.25 at 161 clicking the motor at 1000'. i turned the bottle on at .3 and off at 3.8. 4.51 @ 155 in the 1/8 on that pass. Are you adding the extra fuel through the EFI or are you adding extra fuel through the plate?
I have been changing things all year, so that doesn't have a simple answer. I have had three converters in it, different tunes. I think the cam is wrong, needs more advance and need to play with when to bring the nitrous in. Best NA pass I can recall (don't have the computer with the data in front of me) was 8.01 @ 168. That was in poor air (~3,000ft DA) as was the best nitrous pass.

What are you thinking is wrong or unusual? Do you mean it should ET better for the MPH? The 60" on the quickest pass was 1.201 with nitrous on ~0.5 sec after the car leaves. Just turn the tires a couple of revolutions. All I have control of with the current system is time delay before the nitrous hit. When I go to the high-po nitrous next year I plan on a digital controller. Current system will support 300hp and will try that before the year is over. Want to get a handle on the 74 jet first though.

I have been "guessing" at fuel jet sizes just based on what I know about gas and nitrous and the stochiometry. Just from the chemistry I am using 2.3 times as much alky as I would with gas. The base fuel map is rich anyway, so I am tempted to experiment with leaner to heat it up.

Any thoughts are welcome. I really prefer alky and want to see what can be done with it and N2O. An old timer I know insists that 300hp is practical limit and that power loss vs. the potential with gas really starts to get bad above that. That's why I am wondering about the whole compression thing and trying to figure where to go with it.

Another thing I have been wondering is whether to add the fuel through the injectors instead of plate - which would work better? I am thinking the plate has a better chance of the fuel and nitrous going to the same place.
 

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Discussion Starter #9
BTW: the goal? Go as fast as possible! The car will be bracket raced NA and the nitrous is just experimentation. Eventually if it runs fast enough to quality I might try the local "quick" events. The 1/8 on the quick pass was 4.915, it would take low 4's to be worth entering though the winners are usually in the 3.90's. I am hoping that I can get in the 4.40 range with a plate system and a .110 jet on alky with a progressive controller.
 

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Not best for tuning nitrous advice but according to post 8 you have made a lot of changes w/o a good solid base to work from. I would get motor tuned then go to nitrous. Part of it. When you make lots of changes you get lost easy.Im not insulting you it happens to lots if not most at some point.
Get good base then make changes 1 at a time and anylize the effect before going to next thing.
 

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Discussion Starter #11
Not best for tuning nitrous advice but according to post 8 you have made a lot of changes w/o a good solid base to work from. I would get motor tuned then go to nitrous. Part of it. When you make lots of changes you get lost easy.Im not insulting you it happens to lots if not most at some point.
Get good base then make changes 1 at a time and anylize the effect before going to next thing.
Sounds like good advice. The new convertor is working well with about 5% slip. I am still considering the high CR (15+:1) with alky and nitrous for next year.
 

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man you BBC guys just have it so easy with building compression. Try getting anything more that 13.5 in hemi head motor. Yea could change but have to sale three complete motors and hope I can buy nice 632 bbc then have no spares and I don't race w/o spare for me thats best way to kill motor.If have spare rarely need,run w/o and I'll kill it everytime.
Plus never been one to follow everyone else and there very little out there except bbc and yea I know theres good reason.
 
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