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I don't think you are going to get much response out of 2 turbos that size at all.
If you are only wanting to make 6 psi - just one of those would work fine.

Go to this website and enter your parameters - and it will show you which part of the compressor map you will hit. Pick either of the GT45 turbos to look at. I think you will be way to the left of the surge line with two turbos that bit. It would look cool - but take forever to spool - if they will.

http://www.squirrelpf.com/turbocalc/

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That page doesnt load..... so far I'm getting 2 conflicting
ideas as to lag.. you say they wont even spin up and
the other guy says there shouldnt be any lag
EDIT
Got the page to load up

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I don't think you are going to get much response out of 2 turbos that size at all.
If you are only wanting to make 6 psi - just one of those would work fine.

Go to this website and enter your parameters - and it will show you which part of the compressor map you will hit. Pick either of the GT45 turbos to look at. I think you will be way to the left of the surge line with two turbos that bit. It would look cool - but take forever to spool - if they will.

http://www.squirrelpf.com/turbocalc/

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Where did the red plot line end up after you put in all your parameters and selected 2 of the GT45's? 2 of those turbos means that 1 of them is feeding 208 cubes at a time.

Since you're only wanting 1.5 BAR - you won't be using much of the compressor on the bigger turbos. I'm betting a pair of 60's or 70's would go a long way toward your goals. At least with the squirrel site - you can see where you end up on all those different turbos for comparison.

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Actually the T04B series with62-1 trim drops me right
in the middle of the island

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The GT4508 or the GT4594.

For instance, the GT4594 has the Garrett description in the map itself at the bottom of it.

What kind of power does your 416 make without boost? And what is the expected HP power after adding boost?

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OK. Then I was guessing exactly right at thinking it was an 800hp target.

You will still have a huge window for making more power should you simply up the boost number. Of course, once you start to creep off the RH side of the map - the charge temps go up quite a bit. I'm still impressed about how much lower my charge temps are after going from a single GT4202 to a Chinese T76. I fall right up the middle of the T76 island - so it doesn't melt the full 20# of ice on each pass now!

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I figured there would be plenty left in it if I decided
to turn it up some.. but then you get into the breakage
issue with the other parts... what do you figure a
standard studded head will hold for pressure(SB, not
a R3 block) ... that was why I was thinking to keep
the pressure down

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My 9.5:1 Magnum block, factory head bolts with Iron Ram EQ heads has been very reliable at 18.8 psi of boost for quite a few years now with it's Cometic head gaskets. I haven't gotten greedy with the timing at 22°, and have kept the AFRs between 12.2:1 and 11.5:1 depending upon temps and fuel quality. At the track I try to keep it at 100 octane or more by mixing 91 with 110.

On the street I run it at 12 psi of boost on premium 91 octane - with 20° of timing max.

All with air/water intercooler keeping the IATs at ambient.

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I'll be running 2 air to air coolers and will have
a fair bit of length of alum tubing from out of the
coolers to the hat(I think I'll start out as a carb
but later change over to injected when some money
comes around)

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Thats the same one i run on my 383.Fully spooled to 15 lbs at 3500 r.p.m. Max power at 5000/5200 r.p.m,shift at5500,121 m.p.h quarter

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Are you referring to the GT45 and is it a single turbo

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Next question is on the A/R... the one I said lays
it nice on the island is the 62-1 trim.. now in a lot
of the specs it shows like a A/R .60 and a A/R 1.15
on the turbine side...but yet I cant find a map of
this on that site to see how it lays up

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You will never see an exhaust side map. to many variables. Timing, a/f ratio, fuel type, compressor to engine match, temps, shaft speeds,etc... My advice is start with the largest turbine wheel that the compressor will handle, and the smallest tangential housing that will fit that wheel. You can always step up the turbine hsg, or machine a bit of slot out of it to knock back the drive pressure.
A compressor side that is to small can also drive the exhaust pressures to high. Even with big turbine wheels. When shaft speeds go to high(small compressor) the turbine wheel has the same effect as the compressor wheel. Centif force starts raising ex side pressures "artificially".
Logging exhaust/ intake pressures teaches you alot.

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Next question is on the A/R... the one I said lays
it nice on the island is the 62-1 trim.. now in a lot
of the specs it shows like a A/R .60 and a A/R 1.15
on the turbine side...but yet I cant find a map of
this on that site to see how it lays up

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You will never see an exhaust side map. to many variables. Timing, a/f ratio, fuel type, compressor to engine match, temps, shaft speeds,etc... My advice is start with the largest turbine wheel that the compressor will handle, and the smallest tangential housing that will fit that wheel. You can always step up the turbine hsg, or machine a bit of slot out of it to knock back the drive pressure.
A compressor side that is to small can also drive the exhaust pressures to high. Even with big turbine wheels. When shaft speeds go to high(small compressor) the turbine wheel has the same effect as the compressor wheel. Centif force starts raising ex side pressures "artificially".
Logging exhaust/ intake pressures teaches you alot.

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Whats the difference between the A/R62-1 and the
A/R .60 with A/R 1.15 on the turbine side... would
this work for me

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I'm a little confused with that question. Let me start by saying that turbo nomenclature differs from manufacturer to manufacturer. Then, throw in vendors making thier own names/ numbers.
I'm guessing that you are asking me about a "61-1" turbo.
I'm also guessing that the compressor wheel is designating the "name"
Pay no attention to the compressor Area/Radius. Manufacturers wont machine an incorrect housing to fit a wheel, so pick the correct compressor wheel for your power/pressure ratio, and just accept thst the compressor housing will be best one for that particular wheel.
It's a pretty good bet that this turbo has a "p" trim wheel, though I would confirm this with the seller. P trims will easilly take you to 800hp. I would start with small (low Area/Radius) turbine housings. Depending on the seller, some will let you trade turbine hsgs within a short period after sale, assuming you dont damage them. I would not start out with a 1.15 with twins on this engine, but at worst it will just be a touch lazy coming into boost. It just depends on what kind of boost hit you want. Smaller turbine A/R=quicker influx of boost with less top end power, and vice-versa.
Will they work? Sure. will they be optimum? Maybe. Will they not work? No.

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Thats the whole thing... its hard to compare one to
another if they use different numbers.. sure wish
they had to all play on one standard ... you get some
that use numbers then someone has to throw a "P" into
the game... I dont want it to come on too low... would
like to cruise at little to zero boost but then bring
it in for the upper rpm power(I know I'm asking quite
a bit)... that 62-1 would be about perfect but its
hard to find that actual one(if you can)

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Also... if you're only trying to make such little power increase, why bother with the intercoolers? That boost range (<10psi)will easily run on regular pump gas. Especially with a carb.

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2 reasons Scott.. I have the inter coolers already and
I figured the more you cool the inlet air then there
is less chance of detonation and would be easier
to run pump gas

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I agree with a lot that's been said already. Compressor A/R is a useless measurement for our purposes, but turbine A/R is very important. Trim is also a term rarely used, just look at the compressor wheel measurement.

On 418 inches, the twin 1.05 turbines might be a bit laggy, but they will work. Don't be afraid to look at build threads of Chevy and Ford combos online, similarly sized engines will offer good info about the spool characteristics of a pair of those turbos.

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Looks like I'm gonna try a 60 and a .96

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I bet that will work just fine!

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Hope so.. but thats what I'm gonna try

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I agree with a lot that's been said already. Compressor A/R is a useless measurement for our purposes, but turbine A/R is very important. Trim is also a term rarely used, just look at the compressor wheel measurement.

On 418 inches, the twin 1.05 turbines might be a bit laggy, but they will work. Don't be afraid to look at build threads of Chevy and Ford combos online, similarly sized engines will offer good info about the spool characteristics of a pair of those turbos.

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Looks like I'm gonna try a 60 and a .96

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I agree with a lot that's been said already. Compressor A/R is a useless measurement for our purposes, but turbine A/R is very important. Trim is also a term rarely used, just look at the compressor wheel measurement.

On 418 inches, the twin 1.05 turbines might be a bit laggy, but they will work. Don't be afraid to look at build threads of Chevy and Ford combos online, similarly sized engines will offer good info about the spool characteristics of a pair of those turbos.

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Looks like I'm gonna try a 60 and a .96

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A as in 1? or still twins? I think twin 60/61/67's, would work very well with .96 turbines.

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Twins.... as in 2... so you believe I'm headed in
the right direction

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Divided housings are designed for split manifold diesel aplications. They flow less than an open version of the same a/r, and are usaully cast of a lower nickel content iron. I would pass on these, but I personally have used them. They did end up cracking around the flange inlets, But I was "heat stacking" them, so other's results may vary...

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Thanks... good to know... so I'll be looking for the
larger single opening style

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Switch to E85 non intercooled with the twin GT45 y2004k turbos

My 383 needs twins witch I have but got lazy and didn't feel like relocating the alternator.

Mine car is on Methanol now, lag was never a problem on E85.

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Why would you say no inter coolers... isnt the name
of the game to get a cool/cold inlet charge... you
dont think a pair of GT45s would be a bit muchEDIT
I dont know anything or heard anything on those y2004k

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I think what he was saying is that with E85 or methanol, an intercooler isn't as much of a gotta have at the boost levels that most mere mortals can afford.

With a blow-thru setup the alcohol vaporizing cools down the charge. I'm sure you have seen NA alcohol cars at the track with frost on the intake even on the hottest days. Highschool physics was a lifetime ago but I think the principal was called "latent heat of evaporisation" or some such.

If you are running gas as your main go to fuel the intercoolers are pretty much gotta have if you are planning on more than single digit boost levels.

Kevin

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Being this will be my Drag Week car I cant plan on
E-85(no such animal in parts of the country) so my
plan is regular pump fuel... would like to run 87
but race on 93 octane... that will require some testing
to see what pressure I can get away with on the 93
so the inter cooler are a must(in my opinion).. which
I have a couple... its not like I have to spend money
on them

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Not that I really know anything about this stuff...but you could even consider running the intercooler AND an Alcohol Injection setup while racing....

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I may end up using a meth/water injection set up but
if I can get away with out it I would prefer not using it...
I still like the KISS ways of doing it... once I get
this build up and running I'll test to see what I
can get away with

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You can get away with alot more if you run a cam with longer duration than most "turbo cams". You get a proportional egr effect with rising boost/ backpressure levels. Trust me , this works. you will be able to run any pump swill along the way.

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I assume due to closing the valve a bit later