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Discussion Starter #1
Has anyone dynoed a motor with a 14 vs a 10 this this is on a 565 8.5 to 1 intercooled deal 700 lift 268 have the new dart 380 heads I have heard the extra power it takes to turn a 14 is'nt really worth it anyone tested it?
 

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Discussion Starter #2
boost

that seems like alot of over drive for 9lbs allways many factors but when I had my 10 I was running 17% making 9-10 depending on the temp. outside
I just dynoed with the 14 made 9lbs with 9% over. intercooler is definitely
worth it on the long runs not so much on short drag race runs but insurence
from detionation and you can get away with a lesser gas depending on your combo
 

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Discussion Starter #3
surprised no one has any info on this. I talked to some from a very reputable shop that said a 14 takes 200 + hp to turn and only come's into play after 20 lbs of boost where it's worth useing
 

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i just bought a 496 1471 supper chiller motor runing 800 to 900 hp estimated the biger the blower the less it works there for the longer it last,so to me bigger is beter,dne did a test on a 496 or 509 i cant remember with a 871 on the motor with conservitive boost and it was pushing the limits of the blower at 800 hp there for the blower isnt going to last to long
 

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i just bought a 496 1471 supper chiller motor runing 800 to 900 hp estimated the biger the blower the less it works there for the longer it last,so to me bigger is beter,dne did a test on a 496 or 509 i cant remember with a 871 on the motor with conservitive boost and it was pushing the limits of the blower at 800 hp there for the blower isnt going to last to long
I ran a 8-71 on a 496 for years in ski racing and nostalgia circle racing. Never had a problem with it. At one point with 13% OD it was pushing over 15 lbs of boost, and I did not have an intercooler. Still dont. one does have to have big carbs and make sure you're not going lean.

A 10-71 would not be a bad idea on a 500+ ci motor.
 

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I would be interested in dyno results also, I have heard the same thing and that was my reasoning for sticking with 10-71's. I also wonder if the restriction thru the intercooler is worth the add hp. I have to run 30% overdrive to get 9 psi all that rotor speed causes lots of extra heat.
What carbs are you using? Sounds like you have a restriction on the intake side...
 

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Discussion Starter #8
Impressive

What were the basic specs on this deal? How big and cam? what was it with the 14?
 

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Discussion Starter #9
i just bought a 496 1471 supper chiller motor runing 800 to 900 hp estimated the biger the blower the less it works there for the longer it last,so to me bigger is beter,dne did a test on a 496 or 509 i cant remember with a 871 on the motor with conservitive boost and it was pushing the limits of the blower at 800 hp there for the blower isnt going to last to long
The thing I was try to determine was the threshold balance between hp to turn the 14 vs the 10 I just didn't turn my 10 much more than this 14 to make the same power maybe 3% there is the extra weight as well
 

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What were the basic specs on this deal? How big and cam? what was it with the 14?
10L ARIAS HEMI 557c.u.,8-1 comp,730 lift 270 duration solid lifter,PSI 25%=9lbs boost,24 degrees timing,EFI =1286HP.When the motor was dyno'ed with the 14-71 and carb's,I was told it made 1375,it kept out running the dyno.Those #'s where wrong,I think it was 1050-1100hp.They now have a bigger dyno and the new #'s are more realistic.Now I just need to get it in the boat:|err:|err

Jeff
 

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thats good to know psi's do not make nearly as much heat because I think the intercooler is my restriction, I might be able to remove the cooler and run straight psi. Maybe next season, last year it was both motors and this year it was outdrives.
I have a custom made cooler on mine,I have been told to take it off and i would see more power.The boat is plumbed and I spent alot on the cooler,I'm leaving it on.

Jeff
 

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i just bought a 496 1471 supper chiller motor runing 800 to 900 hp estimated the biger the blower the less it works there for the longer it last,so to me bigger is beter,dne did a test on a 496 or 509 i cant remember with a 871 on the motor with conservitive boost and it was pushing the limits of the blower at 800 hp there for the blower isnt going to last to long

Thats interesting. Because I have a 496 that Dave (DNE) built for me with a 8-71, intercooler running 8-9#'s of boost on pump gas (91oct) that made 980hp. I have been running this combo for 4 years with out a hint of any issues.
 

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custom cooler ok, and hemi's make big power. If they did something for the oiling issues, an old engine builder told me that for 1/4 mile the hemi's rule hands down. but if you stay in the throttle much longer they lose oil pressure to the bottom end. new designs may have fixed this. I still dont see the offshore racers with big $$$ running these in the unlimited classes.
The Arias Hemi(not Chrysler) was originaly designed for offshore racing,Betty Cook raced them and won!!The reason they did not take off,They were to wide and very expensive.The Italians were the only ones staggering engines at the time,now everyone does it.The Arias hemi 10L is no longer in production,The 8.3L is but only in billet block and has no water jackets.The only problems with oiling were the lifters,no oil passages to lifters and dist. drive gear,my builder put spray orfices in these areas.I did not mention it was a drysump with a 20 qt. tank.There is a guy back east that bought all the tooling and says he will bring the 10L back into production.

Jeff
 

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I am running dual 1150 annular discharge 9377's they should not be a restriction.
You're right on the carbs. I think the restriction from the cooler is offset by about 3% OD.

I am only allowed 3% OD overall, so I have been struggling to consider cooler or not. You do lose some boost in the plenum, but the cooler charge may just offset that difference, powerwise. Of course with the cooler, you can afford to run more static compression and more timing safely....

By the way, Amos Satterly of drag engine fame once told me that the chevy head is better for boats on gas. In a drag application where almost pure liquid alcohol and nitro is moving to the cylinder, the hemi head is the right application. This, when he had a blown hemi, complete, fo sale and I was seeing it my GN boat. he actually talked me out of it...
 

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the experts all claim about 100 hp for the cooler we ran no water then with water and gained 85 hp what I wanted to do and did not, is remove the core and dyno. The BDS chart for a 8-71 with 550 cube 30% over is
20 psi, I am running 10-71's 30% over and getting 9 psi ??
Do you have a pic of your engine setup?
 

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Just remember that as you run the motor longer, and it begins to heatsink, the intercooler will have a more pronounced benefit on hp. You will be offset the restriction, with the lower air temp.



Darrell.
 
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