402strokerls1

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).

slammer454

i wouldn't run that much compression, even on C16.

Zombie

iTrader: (2)

wrong compression, wrong trans, wrong gears. I think you should rethink the setup.

402strokerls1

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

will62085

iTrader: (4)

don't waste your time and money on master power. I had two master power t-70's on mine originally, lasted 1200 miles before bearing failure.

Shawn @ VA Speed

iTrader: (3)

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

SSilverSSurfer

iTrader: (8)

tiago ran those same turbos on his set up for the longest. he put down 1k hp with those turbos. he even ran them on his LSX 427 until his TC76's showed up.

402strokerls1

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.

Jimmy P

iTrader: (177)

That compresion seems real high. Anyway you can keep the boost low? How much boost do you guys think he can run if he uses the C16 gas.

MY99TAWS6

iTrader: (3)

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.

Slow Z28

iTrader: (19)

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

Beaflag VonRathburg

iTrader: (176)

What's wrong with a TH350? They'll hold almost the same power if built right, don't soak up as much as a 400, and weigh less.

RDTA

iTrader: (1)

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.

will62085

iTrader: (4)

The older ones were okay, the ones in current production are garbage.

Zombie

iTrader: (2)

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.

1INSANEGTO

iTrader: (13)

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

402strokerls1

what about 116 or whats the highest octane gas i can get, bc i really dont want to go to alcohol but i would like to turn the boost up some

ExceSSive

iTrader: (13)

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.

Big Geek

iTrader: (2)

To actually answer your questions (and not just hammer on your for your desired combo) one would need more info such as - the type of intake and head combo you plan to use. Additionally what the camshaft specs would be as well as the type of intercooler used. As previously stated you are only going to get away with so much on standard race fuel BUT if used in conjunction with alchy injection you should be able to stuff some serious CFM into the motor. Actual "boost" is a relative number that has way to many variables to accurately answer that question as it is truly a measurement of restriction not power but I would say that with the properly sized head, intake, camshaft, intercooler and fuel selection you shouldn't have any problem getting it to 1000-hp plus at the flywheel.

Jim C.

LASTLS1

iTrader: (7)

Buy a HUGE supply of head gaskets!!!