Need some opinions on 2010 LMM build

[pl_silverado]

Trying to figure out what do do as far as fueling and the best course of action utilizing what parts I have on hand.

Going to be building a spare engine. Have the following sitting on the shelf:

Callie’s Durastar Crank
Callie’s Rods
Mahle Motorsports Cast Pistons, Stock bore
Mahle Bearings, gaskets, etc
ARP 4201 Studs
Garrett Powermax 3794 with a billet batmowheel
2 LMM CP3’s, and a 2 sets of stock injectors

In addition to the above,

Last week bought a truck that had an s475 over stock setup with an Exergy sportsman in the valley and stock sticks.


So having decided that the built motor will get an s475/65mm gt3794 setup, what would you guys do as far as fueling that much air.

Is it worth messing with a sportsman and all the stock pumps and dual fuelers or should I just order a 12mm stroker and 100% overs, and sell some of the other stuff on hand to recoup some of the costs?

 

[pl_silverado]

No input ?

 

[gmduramax]

100% LBZ injectors for 800hp
150% for 1000hp

Get an S480

I like the simplicity of a single 12mm but nothing wrong with two stocks

 

[pl_silverado]

100% LBZ injectors for 800hp
150% for 1000hp

Get an S480

I like the simplicity of a single 12mm but nothing wrong with two stocks

Going to stick with the s475 to try to use up what’s laying around, that moneys better spent on fueling at this point. Why LBZ over LMM injectors ?

 

[gmduramax]

LBZ are 7 hole LMM are 6 hole. If I remember correctly LBZ flow slightly more than LMM and atomize the fuel better.

 

[malibu795]

LBZ are 7 hole LMM are 6 hole. If I remember correctly LBZ flow slightly more than LMM and atomize the fuel better.

Yep they are rated almost identically flow wise, but the LBZ tips have 1 more hole so everything is smaller basically ohms law for the sum of everything applied to fluids
X2 on running single cp3 vs 2 for simplicity
Stock fuel rails, HP cross over and fittings? Few people used to sell drilled out/high flow version IDK if they still do.
Not hard to do yourself just clean really well.

 

[pl_silverado]

Took a look at the s475 today after yanking it all
off the donor, looks like it’s the cast 75mm/96mm/1.15 t6

 

[malibu795]

Took a look at the s475 today after yanking it all
off the donor, looks like it’s the cast 75mm/96mm/1.15 t6

That twin setup would make a very comfortable 600-650hp truck, probably get 700+ EGTs though might get warm under prolonged use at that level

 

[pl_silverado]

That twin setup would make a very comfortable 600-650hp truck, probably get 700+ EGTs though might get warm under prolonged use at that level

EGT’s can’t be any worse than they are now towing 10-12k on 35’s. Hoping the regear to 4.56 alleviates some of the strain.

600-650hp with the 65mm in the valley with a 12mm/100% overs? Thats kinda disappointing honestly, was hoping to get to that 850hp range. Or are you talking stock fueling?

 

[malibu795]

EGT’s can’t be any worse than they are now towing 10-12k on 35’s. Hoping the regear to 4.56 alleviates some of the strain.

600-650hp with the 65mm in the valley with a 12mm/100% overs? Thats kinda disappointing honestly, was hoping to get to that 850hp range. Or are you talking stock fueling?

Your limited by the 475 and not really the 65 in the valley in over all HP. I was being conservative on the 6-650 range.

A s480-488 would definitely be easier to hit 850 range

 

[pl_silverado]

Maybe I'll throw it all together on the truck now and see how it performs with stock fuel and stock bottom end while the spare motor is being built. I likely won't finish the built bottom end until the end of this year. Gearing up for a decent trip with the camper this summer, and I don't see myself being happy towing it thru the hills the way the truck is now, after that last trip to Indiana to pick up the donor truck. I kinda ruined it with the 35's but I love the way it looks and rides.

If I sell one of the other trucks before the motors done, I'll spring for the S488SXE.

 

[Bdsankey]

Personally I'd run a single 12mm for simplicity. Less heat into the fuel, less plumbing, less wiring, and no belt alignment issues/hassle. Dual stock pumps will work just fine tho, just not what I'd personally do which is why my truck (with similar goals) has a single 12mm.

As for injectors, personally I would go with a 150% myself with 7 holes vs the 6 hole factory LMM style nozzle. Take your pick on brand, just realize that not everyone's 150% is created equal.

As for air, I think you have an extremely lopsided setup to meet your goals/aspirations. The box cast S475 is your major limiting factor and I wouldn't want to try and push it much more than 700-750whp before you start seeing shaft speed getting out of my comfort zone. This is simply because the box cast S475 wheel doesn't move enough air for more than that IMO. A proper billet S480 would be a solid choice as would a S485. You will not be able to put an SXE in without modifying your piping as your current S475 has the "standard" cover which has a different outlet location and intake size than the SXE V2 race covers. With that said, many aftermarket turbo builders have a "compact race cover" that has the same benefits as the borg warner race covers BUT fits in the standard cover location meaning it's inlet and outlet locations are interchangeable with a standard cover (what 99% of kits are made to). For a 800-900whp truck a S480/96/1.32 will be about right depending on elevation, if you want more capability than that I would step to a S485/96/1.32 sized charger. With that said, I know the builder we use would happily upgrade your S475 to help save some coin on the back end or I know other builders offer the same service.

As for running the 65 vgt/475 on stock fuel, it will likely run ok but will not drive as well as stock charger as the fuel just isn't there to drive the charger's properly and can possibly lead to elevated EGTs/poor drivability.

 

[Dozerboy]

Isn't a 485 a little big for a 65mm? I thought a 483 was the biggest most did. A 483 would do 950hp from my understanding.

 

[Bdsankey]

Isn't a 485 a little big for a 65mm? I thought a 483 was the biggest most did. A 483 would do 950hp from my understanding.

Look at James running a 483-485 over a factory ported IHI.


It works great, I know we've done it many times at my shop to increase power potential as long as turbine flow is there. In my opinion a 485 isn't unreasonable for someone looking to get every drop out of a 65mm vgt. I also use that size as an example as the turbo builder we use for 99% of our chargers does not offer a 483. Even then, the response difference is minimal between the two when using a quality turbocharger as they typically have the same exducer size so wheel weights are similar. Obviously each builder is different in what exducer profile they choose but many sizes share an exducer size, it's very common.

 

[pl_silverado]

I guess billet 480 it is then. Brad send me a pm, give me an idea of price to get mine modified to see if it’s even worth doing.

 

[gmduramax]

I guess billet 480 it is then. Brad send me a pm, give me an idea of price to get mine modified to see if it’s even worth doing.

100% worth doing, you’ll get better spool out of the 65

 

[Bdsankey]

I guess billet 480 it is then. Brad send me a pm, give me an idea of price to get mine modified to see if it’s even worth doing.

PM sent!

100% worth doing, you’ll get better spool out of the 65

That's another huge benefit/reason I prefer a 480 over a 475 in this application.

 

[pl_silverado]

Well the s475 sold and I found this locally for a price hard to pass up, brand new billet Borg 480….

 

[Chevy1925]

I think you will like the 480 but get as much injector in there as you can spend.

After driving a stock over 475 truck, I miss the spool up. That sucker comes on quick compared to the 483. Hard to give up the top end it gives though lol.

 

[pl_silverado]

I think you will like the 480 but get as much injector in there as you can spend.

After driving a stock over 475 truck, I miss the spool up. That sucker comes on quick compared to the 483. Hard to give up the top end it gives though lol.

I think I’ll like it too. Been reading lots of the old posts on here, not much for complaints running the 3794/s480 combo.


I’m gonna go with the 150% lbz’s and a single 12mm.