Author Topic: How much nitro is too much to start  (Read 474 times)

Offline 1320motorworks

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How much nitro is too much to start
« on: September 02, 2021, 03:02:51 PM »
I'm just getting into nitro so forgive me if this is a stupide question. looking into running no more than 20% on my blown injected bbc, and I've read you shouldn't start the engine on nitro. I was wondering where the safe and not safe line would be or is it with ANY amount of nitro you shouldn't. thanks.

Offline tcoupekyle

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Re: How much nitro is too much to start
« Reply #1 on: September 07, 2021, 01:37:37 PM »
Have you read Spud Miller's nitro notes?
I donít know anything about the subject really. But I had allot of fun reading the nitro notes

Offline tcoupekyle

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Re: How much nitro is too much to start
« Reply #2 on: September 07, 2021, 01:38:49 PM »
http://www.fuelinjectionent.com/nitro_new.php

Really nice guy to boot. Iíll be sending him my stuff when the short block gets assembled.

Offline sknopp

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Re: How much nitro is too much to start
« Reply #3 on: September 07, 2021, 01:48:25 PM »
20% is not going to cause you any grief, ASSUMING you are not trying to run high compression on it (over 10:1).  The issue is with nitro on a cold engine it does not want to burn so you end up contaminating the oil.  It gets to be a problem when you're 50% and up.  That's why we start and warm up on alky.  Blown on nitro you'll be fine.  Unblown and injected on nitro is a whole different animal.
 

Offline wideopen231

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Re: How much nitro is too much to start
« Reply #4 on: September 07, 2021, 05:18:35 PM »
I ahve played with 25&. Only cpl hits. It makes big difference, no problem getting enough wheel speed.LOL  While I don't think you will have any issues .I still fire off primer system or bottle if have help.  Just injected no blower. Agree 50% area you get into few more things to do and watch. Guess I will find out myself.   If you have not read spuds nitro notes I too suggest it. Another thing to remember is make sure all of your O-rings are compatible with nitro and alky. DO NOT GET NITRO ON YOUR PAINT JOB. One of the reasons I went with a wrap on my car. Warning this stuff is addictive. One weekend of A/fuel and I am ready for a second powertrain for my car for nostalgia A fuel setup.
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline wideopen231

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Re: How much nitro is too much to start
« Reply #5 on: September 07, 2021, 05:22:03 PM »
Another thing to expect is your stall is ging to go up because of extra tq.Not a ton but probably 400 to 500 rpm
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline msundstrom

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Re: How much nitro is too much to start
« Reply #6 on: September 07, 2021, 05:55:22 PM »
Spud's nitro notes are for NA application not blown application. I run 47% NA and only fire on methanol until the pump picks up fuel, hot or cold. Takes about 15 seconds or less. Can't speak first hand to anything over that or blown application. 

Offline Curly1

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Re: How much nitro is too much to start
« Reply #7 on: September 07, 2021, 07:52:33 PM »
Spud's nitro notes are for NA application not blown application. I run 47% NA and only fire on methanol until the pump picks up fuel, hot or cold. Takes about 15 seconds or less. Can't speak first hand to anything over that or blown application.

How much does 47% pick up your car? What ET you run?

Offline msundstrom

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Re: How much nitro is too much to start
« Reply #8 on: September 07, 2021, 08:55:50 PM »
From 8.0ís to mid 7.40ís

Offline Curly1

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Re: How much nitro is too much to start
« Reply #9 on: September 11, 2021, 06:23:26 PM »
Thanks, I appreciate the info.