Can you help me size a new turbo?
I have had my turbo build on road for about 10k miles.
My current turbo is too hard to drive normally. Light throttle boost, makes this daily driver a handful. Its too small. Its a T-4 housing and a 76 mm compressor wheel.
My car is a 05 Magnum with Rear mount plumbing. I am looking to cut out spare tire well to give more room for a T6. Like a Borg Warner S480? 80mm
Any suggestions on a nice single turbo.
Here is a little about my build.
engine is an Arrington build.
5.7 forged, 6.4.
The turbine is a 75mm with .96 ar
At full throttle the exhaust pressure forces waste-gate open not allowing more than 7psi. On the flip side, I will pull 12 at light throttle. Very hard to tune.
I am getting a new turbo and waste-gate. Looking for great street manners.
From what it sounds like you have a 12lb setup on the wastegate but the backpressure from the long plumbing is forcing the gate open at at 7 lbs. I’m thinking you need two larger wastegate and tune the part throttle boost better. Just keyboard theory here though.
I used a Cxracing T76 0.96 A/R Q Trim turbo to get started...
I am ready to get serious now.
the turbo "kit" i used was really designed for a stock engine and the turbo placement at the axle has serious size limits. the T76 was pushing the limits in physical size.
I am now cutting out the spare tire well.
We are thinking about this turbo; BorgWarner S400SX4 Turbocharger 80mm
Agreed, what you have will make that power, what's the wastegate info on the set up now? I'd bet it's too small and it prob doesn't measure what it's claimed if it's a cheap knockoff version. Add a second and try again with your current turbo.
Both turbo and wastegate were lets say "economical" parts of the original build.
I like the rear placement as it doesnt interfere or overheat whats underhood.
The important pieces that the knockoffs have not perfected yet are the blow off valve and the wastegates. They just cut too many corners and use too inferior materials and have too far lesser machining tolerances. And these are the pieces that usually cause trouble. Bovs won’t stay closed wastegates won’t stay closed, inaccurate spring rates leaks, burrs in the metal causing hanging.
The budget turbos themselves are pretty decent, I would fully disassemble them make sure there is no manufacturing flaws or leftover materials, clean and lube and reassemble, just for my piece of mind. Also don’t follow any of the instructions for oiling. The knockoffs never get it right. No restrictor for journal bearings and the biggest drain you can make. For ball bearing you’d need the appropriate restrictor for your oil pressure.
If it were me, I'd get my WG and spring to the point where I could control the boost down to the 3-5psi range. I was never really happy on the street until I did that, then it was fun to drive again. Something like dbldwn is suggesting would probably be better, but at the relatively low boost you are running, the turbo you have is workable. However you've got to have enough WG and the lightest springs you can get a way with so you're not always pushing all that exhaust through the turbo. I only made 3.5 on the spring and then used a boost controller from there.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
LX Forums Forum
5.2M posts
123K members
Since 2004
A forum community dedicated to all LX owners and enthusiasts including Dodge Charger, Challenger, Magnum, Hellcat, SRT8, and Chrysler 300. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more!