nos question

Old 11-12-2007, 11:06 AM
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Default nos question

i am running a 871 blown 468 bbc in a tube chassis beretta, i am making about 12 pounds, engine is well built callies crank etc,car goes 5.54 at 125 in 1/8th on gasoline,thinking about spraying a 100 shot of nos on it.any suggestions on whether this is agood idea or not and how much it will pick up?
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Old 11-12-2007, 06:10 PM
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id be worried about pushing the head gaskets out. but im sure somebody will chime in that knows more about it. jmo
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Old 11-12-2007, 06:15 PM
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Why mess with nitrous? its got a blower! can you say , o-rings!!! copper head gaskets!!!! David.
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Old 11-13-2007, 06:12 AM
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Default o rings

motor has copper head gaskets and o rings in it.
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Old 11-13-2007, 06:42 AM
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Default try another pulley

why not try another pulley and get a couple more pounds boost? add a bit more fuel and take a little timing out to be safe...best to play on the dyno if possible...
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Old 11-13-2007, 08:38 AM
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i assume since you are on GAS you are running 2 carbs.????....

if you want to get 1/2 second off your E/T...then take off the carbs..put on a injector (my choice Birdcather) ..buy it new and they will set it up for you engine set up before it leaves their shop..run top nozzles only, i would run a cam driven fuel pump, or you can side mount it and run belt off crank.

this means moving at least a 5 gallon cell to the front if not 6 gallon depending if your running 1/8 or 1/4...

if its o-ringed with copper head gaskets,,turn the boost up to about 16 pounds minimum...

that will wake her up....just deal with the right people in getting this set up ..such as Jim AT ENDERLE in Califirnia..i am sure there is more out there but i have delt with Jim personally and he was dead on with me..

your approx cost for parts to do this,,assuming you do the work.

#1 dynoed birdcatcher injector $1375.00 ( sale the carbs to off-set)
#2- the pump will cost you $400,with cam drive ext another $150
#3- tank $150.00 or make it for material cost
#4- plumbling $$..Good Vibrations make a $80.00 loop back set up that does away with all those return lines to the tank..it just circulates back into the pump itself..pump will never run dry.


so i would say under $1800 you can have it 5.0's maybe 4.99 ish if your set up is what i think it could be...

with alcohol you will not have to worry about detonatation.

thats cheap for this kind of E/T gain..most people pay close to this just for a carb only..

you can buy this stuff used but i would not fool with it unless you know your stuff on how to re-set everything..or be prepared to send it off.

thats my cents.

Brian
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Old 11-13-2007, 10:32 AM
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Default enderle!

ditto what Brian said! only i would run down nozzles as well, makes fine tuning of individual cylinders so much easier and precise. have seen BBC's run very well with only nozzles in the hat though...


have talked and dealt with Jim at enderle as well and he will definitely show you the way!
Ken
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Old 11-13-2007, 11:42 AM
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motor is only 8 to 1 comp is that enough for alcohol,i have 2 825 carbs on it now,what about switching to 2 1095 dominators on alcohol?
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Old 11-13-2007, 12:45 PM
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your 8 to 1 static compression correct ?...which means before any boost is introduced...after bumping up to 16 lbs i promise your final compression ratio will be just fine for the alocohol..there is a final CR chart after boost..i have it packed away somewhere,,it was in my BDS catelog......and its an easy fix if NOT..take off the heads and have them angle milled to your desired static compression is reached..personally i would run what i had before doing that.
the old 8 to 1 compression street blowers was set beacuse there was a very low boost range (5lbs)...which still meant you could run pump gas on the street.....


i do not know what kind of a blower you have...if you have an older weind street blower or something like that you might be making all the boost you can...even if this is the case you can send it off to Mert Littlefield and they can line bore the case and strip or restrip the blower...which could failry easy double your potential boost..much much cheaper then buying new blower..

i ran a 671 BDS Stage 4 BIG BORE competition blower that was anadozied and stripped with nylatron and teflon ( alcohol/nitromethane) compatible...anyhow this blower was capable upward of 40lbs of boost...because of the type blower it was and the tight rotor tolerances..i only RAN 26 LBS for the record..


11 to 1 to 12 to 1 static is what is ideal for alcohol motors...but and 8 to 1 turning 16 lbs of boost will respond in a big kind of way COMPARED TO WHAT YOU HAVE..plus the injection will be so much more responsive than carbs.....
also do not know what your running for igintion...but if its less than a 7al..your gonna have to go to a 7al box MINIMUM..this will be enough to light the alcohol...but if you really want to do it right..a Magnetto will work best..i also ran a PRO-MAG 12 on my 572 blown injected altered.

also your gonna have to run a colder plug 2 or 3 steps colder and run around a .16 gap but no more than .20......


any other questions...there is plenty more folks on here with plenty of experience to share on this subject with you.


ps...for what you would pay for (2) GOOD BLOWER dominaters you could have done switched to blown alcohol and saved yourself a grand or so..

if your gonna stay gas and carb,,then do not waste the money on more carbs..
my opinion..i just do not hink for the money you will get the results you desire.

Brian
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Old 11-13-2007, 01:00 PM
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thanks a lot for all the info,i am running bds stage 2 871 and7al3box i will be looking for more good ideas.
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