not building enough boost ???

triton

triton

Scarlet Fever
I'm hoping to get some ideas as to why I can only build 52psi of boost when I should be seeing 80. I was hoping for 800's on the dyno but was only able to get 680hp.

twins are BW's 66/480. Top turbo has a HTT SS housing which as far as I know has the updated wastegates. Top turbo is using the spring style gate controller which has about 1/8" to 3/16" of movement.

They build boost I believe as they should 1:1. According to the gauges primary will get to say 40, secondary at 20. Over all boost runs into a wall at 52 though.

No leaks other than a small one I found at the flange of the top turbo and hot pipe. Don't think it's big enough to be down 30psi though.

any help is much appreciated
 
I believe I have plenty of that. This was taken today on the dyno

37266_1374098586186_1043447113_30868112_4992578_n.jpg
 
yes and yes. It feels a lot stronger on the street than when it was on the dyno. I barely felt it pull there.
 
ty- mine has seen a highest of 68 psi @ 958 hp .... no boost leaks/soot

i dont know why others are seeing huge boost numbers- i have a cam...... but NO head work/porting
 
the 480 is not gated. No I haven't checked for leaks but, I put this thing together and I'm 99% confident in what I did. All Mr. Bob's hose, all Mikalor clamps, everything torqued to spec. It builds great and the bottom kicks in where it should. Just hits a wall ???

Joel, I'm positive that extra 16psi of boost you have would make a big difference for me. I know though I should be able to get much more. I know someone else running 75+ anytime he wants....that's with a 64 on top.
 
now are you using just the internal gate of the top turbo or are you running a external waste gate? do you have a driver pressure gauge hooked up. drive pressure and boost pressure will be about 1:1 until the waste gate becomes a restriction and then the drive pressure will start to climb with no increase in boost pressure.
 
How are you measuring 20 from the second stage? FWIW, I'm only driving my primary at 25 psi and my secondary is doing 17, for a total of 70 psi. It seems to run better the harder I work my secondary. At least with my current fueling.
 
ty- dyno is a tricky thing- to much fuel applied at the wrong time and kill the power

with my 64/480.... maybe the hammy cam is awesome (i love it) i have not seen over 70 psi EVER and im running 220's now -829 hp diesel only- instead of the smaller 150/ish (75% E.H.)

it looks like you had to much fuel and the turbo(s) couldnt fully light and the dyno run was over..... what was the starting boost before the dyno run started? i usually like atleast 10 psi before the dyno button it hit.
 
Video of it on the dyno? I see a bunch of smoke on spool or early in the pull....I'll bet its EPA clean at full song. You should hit 75 like nothing.
 
It looked like on the last pull he built some boost before laying in it. At least thats what it looked like from where I was. Seemed like a good pull.
 
using a MP-8 for the fooler which was just reprogrammed last week.

I have the cold pipe tapped for reading the bottom turbo and tapped at the intake plenum for total.

I know what you're saying about the dyno not loading but, Dunbars been doing it a long time though and he would have said something. He was confused too. It really didn't feel like the bottom lit like it should though.

Joe I was in the truck so I didn't see. No video but, I'd guess you're right. It does that on the street anyway.
 
B18B1LS1 said:
It looked like on the last pull he built some boost before laying in it. At least thats what it looked like from where I was. Seemed like a good pull.
Click to expand...

Yeah, he was on the brakes. The pull seemed short and the turbos didn't sound like they lit like they should have. We both were watching the boost gauges though they built..... and stopped.
 
Someone check my math but it sounds like your secondary is making 3.2 psi if your primary is infact making 40 psi. Try closing the wastegate completely and see how it behaves just for testing purposes.
 
B18B1LS1 said:
Someone check my math but it sounds like your secondary is making 3.2 psi if your primary is infact making 40 psi. Try closing the wastegate completely and see how it behaves just for testing purposes.
Click to expand...

Ok, if I were to do this and it still only did 52, what would that mean ?
 
Ty on my truck i built last year i ran a silverbullet over 480 with spring gate on top turbo. No matter what i did it never seen above 60psi. Did 726 with a smoke out, but yet on street it cleared 150s instanly.
 
I would take the mp8 of and just run a fooler that plugs into the map like a quadzilla or something.If it flat lines at 50 on the street and will not go no more no matter how hard you push it ,that sounds like a electric problem to me.How much boost did the single 66 make you used to run.
 
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