408 11:5:1 compression, twin master power 70s
#1
408 11:5:1 compression, twin master power 70s
i'm in the process of putting twin master power 70mm turbos on my 11:5:1 408 behind it will be a turbo 350, moser 9inch with 373 gears, what does everybody think the horse power numbers will be and times and how much boost could i run if i'm running c16 race gas (116).
#4
my motor is already built and thats the compression that i have right now, i know, i would rather have it down around 8:5:1 but i'm going to have to deal with it right now, the gears can be easily changed though
#6
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looks like an ad for all the wrong things to do on a turbo set up,the only way you could run that motor and put any real boost to it is to run straight alcohol,short of that it's not worth firing up,knock the compression down and get some good turbos
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#8
guys i was just wondering if anybody else has done this, i know all about the compression stuff, i dont plan on throwing 25lbs of boost to this thing. i plan on just building it up as i get the money.
#10
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Well if you can run 7.5 on factory 10.5 to 1 would think you could easily run 7.5 on 11.5 to 1 on c16. And if you keep timing down maybe quite a bit more. Only real way to know would be scan the engine carefully watching knock retard like a hawk. Of course also good to have big intercooler as well. You could also throw some large chamber heads on their for a quick drop on compression. Not sure how much it would drop...half point maybe to 11.1.
#11
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i gotta agree with a couple of statements being said about gearing and "maybe" the trans depending on how built it is. it'll still be shortlived. th400 or a powerglide at some point down the road might be better solution
as for the compression, i'd say if you can get a cam to help get the DCR to where it's a bit better for what you are trying to accomplish, that'd be a good start.
what size cc chamber are you using now? If it's something like a 59cc patriot head, etc.., maybe try finding a 72cc head to help bring the compression down a tiny bit. I'm not gonna say it's REAL HIGH won't ever work, type thing(there is a local guy running 10.5-11:1 in his 3rd gen SBC w/ an ATI running 16-20lbs going high 8's if memory serves me right)
High compression, low timing, big boost = decent e.t./mph for him
MUST match the setup as best as possible
as for the compression, i'd say if you can get a cam to help get the DCR to where it's a bit better for what you are trying to accomplish, that'd be a good start.
what size cc chamber are you using now? If it's something like a 59cc patriot head, etc.., maybe try finding a 72cc head to help bring the compression down a tiny bit. I'm not gonna say it's REAL HIGH won't ever work, type thing(there is a local guy running 10.5-11:1 in his 3rd gen SBC w/ an ATI running 16-20lbs going high 8's if memory serves me right)
High compression, low timing, big boost = decent e.t./mph for him
MUST match the setup as best as possible
#13
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I know it will work. i run a 12.5 sbc with twin 70mm master powers. c16 no methanol, no intercooler and went 6.01 @ 120 in the 1/8th at 10lbs. i know its not a ls1, but with the right tuneup.
#15
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Nothing is wrong with them at a resonable power level, but I've read about issues with people killing them more often then I have about people killing TH400s. When I bought my Trans from Rossler I asked about a Th350 and he said that a Th400 would be more reliable in my application and cheaper to build.
#16
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If you are willing to run e85 you will not have a issue even though people think different by they have never tried it.
I have a friend who is running 13.5:1 compression on a 347ci mustang with twin 76's on alcohol and to top it off blow through and the power comes on so fast its crazy.
At your compression level E85 and 96lb injectors is the key and should be a sick combo. My next project is a 454LSX 14.5:1 compression on 106 running alcohol. Can you say instant spool
If you are willing to go alcohol then its a lot cheaper. You don't need to run a intercooler, radaitor, or water pump. To top it off its 4.00 to 4.50 a gal. So if this is not a street car think how much you would save on your build
I have a friend who is running 13.5:1 compression on a 347ci mustang with twin 76's on alcohol and to top it off blow through and the power comes on so fast its crazy.
At your compression level E85 and 96lb injectors is the key and should be a sick combo. My next project is a 454LSX 14.5:1 compression on 106 running alcohol. Can you say instant spool
If you are willing to go alcohol then its a lot cheaper. You don't need to run a intercooler, radaitor, or water pump. To top it off its 4.00 to 4.50 a gal. So if this is not a street car think how much you would save on your build
Last edited by 1INSANEGTO; 01-13-2008 at 05:48 AM.
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I would say start at 5lbs and go from there. I have a friend in Vegas with a 383 12:1 or 13:1 (don't remember) and he is running a procharger at 4psi and making around 700 or so. I would say start low...you can always turn it up.
Or as suggested what cc hear are you running...increase to something bigger and get down to 10:1 and you could run 10-15psi. Just a thought. I think an intercooler is essential and meth inj. is a good safety measure.
Or as suggested what cc hear are you running...increase to something bigger and get down to 10:1 and you could run 10-15psi. Just a thought. I think an intercooler is essential and meth inj. is a good safety measure.
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i'm in the process of putting twin master power 70mm turbos on my 11:5:1 408 behind it will be a turbo 350, moser 9inch with 373 gears, what does everybody think the horse power numbers will be and times and how much boost could i run if i'm running c16 race gas (116).
Jim C.
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i'm in the process of putting twin master power 70mm turbos on my 11:5:1 408 behind it will be a turbo 350, moser 9inch with 373 gears, what does everybody think the horse power numbers will be and times and how much boost could i run if i'm running c16 race gas (116).