Don't worry about spool up with the right cam Turbo kit and a nice tune it will spool faster than you think. I hit 16psi by 3500 max haven't tried 20psi on the street yet as I need a lot of road to do that! And this was with a cast wheel Turbo. I've got the billet to bolt up next and that will spool even quicker

 

With my valve closed that pins gate I make 15psi or so at mid 3000rpm range. Afraid to let it pull much higher than that with gate pinned. Afraid it'll make 25psi and grenade the (good luck, nothings broke yet) ls1.

 

im running a rear mount pt7175 and it is making 772/767 on my 5.3. its gone over 800 already. and we think it will make closer to 900 on pump meth and klotz. I think you need to turn up the wick!

 

A billet wheel won’t spool up any faster than a cast wheel of the same dimensions. If anything a billet wheel is heavier as it is more dense. Billet wheel turbos were created for strength and longevity in diesel applications. They are more of a gimmick than anything in the performance world. The reason most billet wheels make more power is because they are a different blade profile and or size than the cast wheel they replace. This is straight from the mouth of a design engineer at Borg Warner.

I wish they would all go back to cast and cut the price of these turbos in half.

 

I ran a billet and cast my logs showed 700 rpm better on spool up on the brake just haven't ran the billet yet on my 370.....these were same tunes same boost same fuel maybe bullseye does something different with their wheels

 

Anyone maxing 1000+or trapping north of 160mph on a Cast S480 in a t4?

The wheel can make it, on paper, but I don't see anyone running them that hard.

 

I'm sure it did, like I said the wheels would have to be the same dimensions. The billet "race" wheels performance companies sell are different dimensions than the cast wheels they replace. In other words if they made a cast wheel the same dimensions it would be cheaper and perform just as well. The fact that it's billet basically means it's shiney... and they can charge more for it. Thats according to the guys at BW anyway. Makes sense to me. What is the purpose of a billet wheel?

 

Im not big on rwhp dynos but my billet v2 S476/92/T4 traps mid 164 out of gear on rev limiter @3300+ lbs. It will go 167-168 or so I think with more gear and turbo maxed out. I have a cast S480/92/T4 that runs about dead even with it and it has gone 6.0/117.xx @4800 lbs. they will both make 18psi at 3300 rpm within a couple seconds but the billet 76 comes up a good amount quicker.

 

I'd be satisfied with that. My turbo kit is a true PTK hotside with t4 flange. The cam is a custom Tick turbo cam that should work well with an s476 or s480. Guess it's time to take some measurements and make sure I can actually fit the massive thing on the PTK hotside lol.

 

Wow!!! Now that is moving out! What kind of boost are you running on the s476 to trap those speeds?

 

sorry, some of your info is incorrect. The billet wheels/FMW turbos that B/W sells are heavier wheels than cast even if the sizes are the same. You use Forced Inductions's billet wheels, or Bullseye's they are lighter and have different profiles, even if the sizes remain the same they are lighter. Again, the factory billet/FMW wheels are heavier than the cast counterparts. I run a diesel repair/performance shop with my brother and can tell you first hand the FMW wheels spool slower than the FI, or Bullseye batmowheels.

 

the purpose of the billet wheel is durability. The cast wheels can come apart at higher boost levels. I chose a FI billet v2 wheel on my s480 was for quicker spoolup in my tbss

 

None of my info was incorrect. You just reworded it. I said a cast wheel of the SAME dimensions as a billet wheel will be lighter. Thats a fact.

On race applications your not going to stress a cast blades. Billet was introduced for for longevity in the big rigs. 300k+ at a constant 20+psi on a diesel would eventually stress the blades. Light duty drag/street applications don't have this issue. I've seen cast wheels withstand 120psi+ without an issue on compound tractor setups. Durability IS NOT an issue with drag racing.

Where are you getting your information from? I'm not saying your wrong, but I've yet to see anyone weigh the compressors your talking about VS a cast replica of the same wheel. The billet unit would have to be considerably "thinner" to be lighter than a cast unit. None of the billet wheels I've personally had my hands on ran a blade any thinner than the cast units. I've yet to see this. Also you can't compare wheels with totally different profiles and claim one out performs the other because of the material it's made of. It doesn't matter if the company sells a billet s475 and a cast s475. Those are just names, the wheels are totally different.

 

Just redo the flange to a t6 divided and you will be good to go. As I've said many times the twin scroll is a huge part of faster spool up

 

Its called Testing different setups. I've had compounds on my duramax, ive had cast, billet singles on it and i will be getting another billet v2 drop in wheel for it since i just did a FI s366 on a different dmax, and guess what.... it spools faster! and pulls harder than mine.

 

Impressive. Who's billet 76 are you running (there are so many out there). Also- the 92mm turbine is the "new tech" BW stuff correct? Last question-what AR t4?

Thanks a ton!

 

Ok... I'm happy for you, whats your point? You aren't contradicting anything I said.

Unless you tested an exact cast copy of the billet wheel you claim is "faster spooling" and tested them back to back you aren't saying anything useful. Of course the "billet" wheels will run better. They are a better (and usually larger) profile wheel.

What I'm saying is the current wheels aren't so complex that you need a 5 axis CNC machine and a chunk of billet to make them. Take that same "super billet" wheel and make a casting of it. Then mass produce it for half the cost. It could easily be done. It isn't because there is a larger profit margin for the shiny wheel turbos.

Here is a great article on it...

http://www.enginebasics.com/Advanced...%20Wheels.html

Straight from BW....

Even Garrett Claims there is no gain in performance to be had!

 

You are correct that a billet wheel vs a cast wheel for the exact same dimension will perform the same-but you (and Dmax to a point) are bit off everywhere else.

You have to take the BW quote with a grain of salt-after all, he is trying to sell turbos! The true reason of why there is so many billet options on the market is low production number turbos (its cheaper to cut billet than create a casting for low production) and the fact that billet is significantly stronger means you can get away smaller shank and blades-which was mentioned. PTE's billet wheels for example are MUCH thinner-and allow for more effective area. The PTE6266's inducer for example is only 1mm lager than a 35r, but because the Shank is almost 2mm thinner (and the turbine blades are also significantly thinner) you get much more effective area-and in turn a turbo that can flow 150 more CFM with the same or better spool characteristics. Not because it is lighter-its larger-heavier-but simply flows more air than the 35r at any given shaft speed.

The notion that it was for OE use is silly. A good friend is the lead tech at the local Truck (Semi) shop. He sees about 20-25 new rigs in the shop for service a week. I have asked him to take note of the turbos on the tucks for the past month. You know how many have come through with OE billet turbos? Zero. Obviously this is third hand info-but I also asked my local freightliner dealer-and he told me none of the trucks on his lot came with a billet turbo stock-but you can upgrade for a price

Also-saying they don't blow up in drag racing or at @ XXX psi is also silly-you know better than anyone-pressure vs flow. If you go to any event where turbo pro mod cars are running, you are all but guaranteed to see a turbo grenade due to the wild shaft speeds they run. Hell I think atomicfusion even narked a few turbos-one almost causing his car to burn down. He's not running anything near 120psi.

 

You are so wrong it hurts... I'll happily agree to disagree, cuz that's a huge load of BS. I'll give you the easier to manufacturer for low production volumes... but that has NOTHING to do with performance VS a cast wheel.

Read the link above...

 

This is the point i was making. the aftermarket billet wheels are still 80mm but are thinner in the blades and hub area, thus being lighter and stronger than cast.