Hey guys,

I added an ebay twin turbo setup to my old truck and am showing zero boost until 6500 - 7000 rpms. Which is over revving my engine.

The turbos are mainly for looks, but I'd like to have something. Having small turbos I would have thought they would have spooled well before 6500-7000k.

Engine: 350 sbc
Wastegates: 38mm, 8psi springs, they don't even open up
Blow off valves: Not doing anything

Turbo:

Compressor:
Trim: 55
A/R: .50
Inducer: 50.50
Exducer: 76.00

Turbine:
Trim: 73
A/R: .63
Inducer: 65.50
Exducer: 55.90

Besides sounded good, they aren't do anything.

 

pics. I don't have any newer pics, but I have the exhaust down pipes on now. Turbos are spinning pretty quick. I can take a video if needed.

 

I'd check for boost leaks first.

 

So wait, your saying they boost very fast, as in you can hear them spinning, but your not feeling or getting useable boost untill very high rpm?

I dont see much room for boost leaks from the picture, BUT there is never a good reason to not check for those first.

I would think as well that even those those are not *small turbos, they should be a bit quicker. But that does have alot to do with exhaust temps and flow. What is the brand of turbos your using?

 

Should be boosting by 5000rpm with 50mm turbos. Are you sure the wastegates are not leaking?

 

Could it be that the wastegate collars are installed upside down....or not at all.....?, leaking exhaust pressure that should be spooling the turbo...