Danny

iTrader: (16)

Hey guys,

Here's my dilemma....
I'm using a pair of ebay GT45 turbos to feed my LS3 powered fbody. I've already purchased a Callies dragon slayer crank from a forum member that I'll be using. I want to build a big enough motor to spool those turbos on the street without having to make the engine scream. Now I know that a lot of things like cam, torque converter, etc, etc all have a lot to do with how a turbo will spool but I'm just asking in general.

What size motor would be a good size for these turbos???

Options...
#1. Buy stock size (or +.005) pistons and build a 416ci.

#2. Send the block to RED and have Steve resleeve it and punch it out to 427-433ci.

Would option #1 be good enough or am I going to have to fork out the extra 2k to have the block resleeved for a bigger motor???

Also, what rods do you guys recommend that won't break the bank?

My goal is a minimum of 1000rwhp

Danny

iTrader: (16)

Any thoughts?

oldschoolmuscle

iTrader: (5)

id just stud the ls3 and do ls9 head gaskets and do a custom trq convertor and custom cam and springs.

i don't see it being a issue meeting your goals.

baggins

iTrader: (21)

Was thinking about trying this with a 404 lsa headed setup... in for details

Danny

iTrader: (16)

I'm sure the stock cubed LS3 will make the power that I want but I don't want to have to spin the motor to get good response. I want to minimize turbo lag while on the street. So you think a 416 will be more than enough to spool those turbos early on?

I was also thinking about using the LSA heads but Richard @ WCCH said they do not benefit from the thick decks like the LS9s do. So I figured I will just port my L92s, replace the valvetrain and valves and install some LS9 gaskets with studs. I'll eventually upgrade to LS9 heads though.

Cronic_Moronic

Why would you spend 10k to build and engine to use $300 turbos?

w94rx7tt

iTrader: (1)

I wish there was a like button.

Danny

iTrader: (16)

Im actually not going to be spending anywhere near that amount but thanks for the comment.

Now back to the topic at hand. Does anyone have any other suggestions?

ws602

iTrader: (2)

Have you considered a Lsx block to make a 427?

71 chevy

iTrader: (18)

instead of contemplating spending 2k to spool $500 worth of turbos, why dont you sell those turbos, maybe lose $200, and buy the correct turbos for whatever engine you build.

Math was never my strong suit but it seems to me like you would come out money ahead.

now, 1000whp on street. you sure thats gonna be enough power?

Danny

iTrader: (16)

I would prefer to keep the LS3 block I currently have. The only reason I want to go bigger is to just help with spooling the turbos earlier. If I can get away with resleeving it for even more cubes then that'll be cool. Good idea though.

I see your point but im not looking at buying more expensive turbos right now. Im on a budget here. I asked if I could get away with a 416 And be good or if something bigger would be required. If a 416 will do the job then I won have to spend the 2k on the block.

It's going to be a track car but it's also going to be my wknd warrior so to answer your question...1000rwhp might be enough....for now.

Danny

iTrader: (16)

So what do you guys think??? Would a 416 be more than enough to spool these turbos?

LS1NOVA

iTrader: (12)

Those turbos have 77mm turbines. Pretty big to have any hope of spooling but since you say its a track car, try it out and tell us how it worked. There is a local guy here in MN that used two china GT45's on a BBC Chevelle and ran it in the Dynomax power to the wheels challenge. Google it but I think he made upwards of 1500rwhp.

Either sell those and get something more in the efficiency range or prove us wrong.

DrTurbo

iTrader: (3)

Go with the BW366. We use them on many 400-450LSX setups, and they work awesome.

Danny

iTrader: (16)

I think I remember reading about that car. If I remember he came in 2nd in some dyno challenge. He used a pair of MP GT45 turbos. Well, I guess I'll just build a 416 and run it on E85 so help spool it a little quicker.

The plan is to later upgrade the turbos with a pair of BB units that perfectly match my setup, but for right now the GT45s will be enough to play with. I've been wanting to see what kind of power these turbos can make in a "twin" application. A lot of guys have used them in "single" setups but not really on "twins". I'll definitely check back with the results.

Doesn't that turbo have a bigger turbine than the ebay GT45s? I could be wrong...

2005vetteTT

iTrader: (1)

Largest on a S366 is 73mm. GT45 is 77mm

Danny

iTrader: (16)

You're probably right. I was probably thinking about a different turbo. For some reason I thought it had a 80mm wheel.

DrTurbo

iTrader: (3)

The exducer on the S300 is 73mm. They are smaller frame units and run .91 divded housings.

baggins

iTrader: (21)

any updates on this?

LilJohn

You wouldnt be able to tell the difference between a 416 and a 427. Spending 2 grand to do that is the biggest waste of money you could possibly imagine.

Those turbos will spool just fine on that cubic inch. If a 427 can spool a pair of borg warner S475's with 96mm wheels and 1.32 housings.... a 416 spooling a pair of those 83/77's with 1.01's shouldnt be an issue....AS LONG AS THE REST OF THE SETUP IS DONE CORRECTLY.

This setup will not make boost 200 rpm off idle. It will not act right with a 224/228 camshaft. It will need some converter and it will need a medium sized cam. Low to mid 230's @.050 on intake. Mid to high 230's on exhaust minimum.

Now. Why do you want this thing to spool so quick? A 416 makes a ton of torque on its own. Do you have the chassis and tire to be able to actually USE 1000 lb feet@ 4000 rpm/10-12 psi??? Ive driven cars that can do that... and its completely useless on the street.

Have reasonable expectations of WHERE you want the power to happen. It will make for a much more enjoyable driving experience. Having to worry about wrecking if you give it too much throttle all the time isnt fun.... at least not to me.