3794 turbo braking

[Chad006]

Hey fellas, I’m in the process of piecing my engine back together after a crank break. Just trying to decide on what direction I want to go with the turbo setup. Was running the 68mm 3794 from sdp with a 480 atmosphere, all in all it was a very well rounded setup. The biggest downfall of it was I found the turbo braking to lack and was a bit laggier than I expected. The truck is pinned to a trailer for a majority of its life when it’s not at the track. Is there anything a guy can do to the 3794 to make it brake better (different vanes)? I know everyone rants about the braking on the Danville stg2 R turbos.

 

[gmduramax]

I loved the 3794 from Danville. It was the 65mm and it spooled better than the factory turbo. Never had a complaint with the turbo brake. I believe the stage 2r turbos wouldn’t spool or brake as well as the 3794 but I could be wrong. It’s been a while since I looked into it.

 

[Nate’s Dmax]

My 68 stage 2R from Danville barely does anything. They are designed for flow so they will not restrict like a factory one.

 

[Yngdmax92]

My 3794 stage 2 with high flow vanes is very comparable to stock turbo breaking, I was very admit on keeping this function when buying a new turbo. Absolutely love my Danville 3794

 

[Bdsankey]

What are your overall goals for the truck? In my opinion it is hard to beat the responsiveness of a small drop in turbo, especially in a 800-1000whp compound setup.

 

[Chad006]

What generation truck do you have? Stock turbo brake on lmm’s are pretty impressive, does Mark change the vanes on his stage 2 3794?

 

[Chad006]

My goal for the truck was to run high 10’s and still have a truck that can tow and function as a truck should. And honestly I was extremely close having ran close to a dozen 11.0 passes while still pulling every darn trailer on the farm lol I had just purchased my drag radial setup and was getting nitrous dialed before the crank broke. Going to be running a durastar crank and a few other odds and ends on the fresh build. I honestly can’t complain about the setup, other than I just miss that factory exhaust braking. If there is anything that can be changed on the 3794 to get that back without sacrificing performance.

 

[2004LB7]

if everything else runs good why not just add an exhaust brake?

 

[08lmm72mm]

My goal for the truck was to run high 10’s and still have a truck that can tow and function as a truck should. And honestly I was extremely close having ran close to a dozen 11.0 passes while still pulling every darn trailer on the farm lol I had just purchased my drag radial setup and was getting nitrous dialed before the crank broke. Going to be running a durastar crank and a few other odds and ends on the fresh build. I honestly can’t complain about the setup, other than I just miss that factory exhaust braking. If there is anything that can be changed on the 3794 to get that back without sacrificing performance.

Marks stage 2 3794 is a 65mm turbo. So if you switched to his you'll gain the turbo brake at the expense of 3mm

 

[Chad006]

if everything else runs good why not just add an exhaust brake?

Ya I have been looking into doing this already just didn’t want to complicate things more than I have to. Plus the additional weight associated with tanks and compressors.

 

[Chad006]

Marks stage 2 3794 is a 65mm turbo. So if you switched to his you'll gain the turbo brake at the expense of 3mm

Boy if I had a nickel for every time I was 3mm short lol But seriously the setup ran real hard and I have very few complaints, just thought that maybe it could be improved. Another thought I had was to throw the factory charger back on and gate around it and spray the life out of it lol anybody on here ran a setup like that?

 

[juddski88]

What do you have for fuel?

 

[Chad006]

Exergy 12mm and 100 over lbz injectors.

 

[jlawles2]

You could setup the exhaust brake with quick connects. Go to track, pull a couple of connectors and then the tank compressor setup.

 

[Bdsankey]

IMO a smaller VGT with a more aggressive/street oriented vane setup (like a 64-65mm inducer 3794 from someone like Danville, Dan's, Titan, Fleece, Forced Inductions etc) will be a better fit for what you're after in terms of spool up and turbine braking.

 

[Chad006]

Do you think the different vanes really make that much difference in braking?

 

[Bdsankey]

Do you think the different vanes really make that much difference in braking?

100%. The vanes themselves and the unison ring are major factors in response and flow. Obviously larger/more free flowing designs will make greater peak power but at the cost of response. Being as I have no clue what or who SDP uses to make their VGTs it's hard to say what they did, I'm speaking purely on my experience in personal and customers trucks.

 

[Chad006]

As far as I understood it’s just a factory 3794 with the machining done to stick a 68mm comp wheel in it. Nothing done to the back side.

 

[Chevy1925]

the vanes will depend on the options you got with the turbo. you could get high flow vanes

if you go with the tighter vanes, you may run into drive pressure issues on nitrous and need a gate around it. if you already have the tigher vanes, id look at the tuning on it or make sure the vanes are fully cycling.

how much rpm are you letting the truck have when using engine brake/turbo brake down a grade?

 

[Chad006]

I didn’t realize there was different options on that charger. Is that a Garrett option? I definitely wasn’t given any options when I purchased the turbo. Wonder if there is any way to identify the vanes that are in it? It gets all the rpm, I really hate using my brakes. I use the tap shifter and tow haul even unloaded.