The Project Pad

It struck me the other day that it seems like a LOT of project cars go through one or more turbos in very short mileage. I am wondering why? Are aftermarket turbos weaker? Are peoples oil feeds/drains bad? People running without filters and eating random things (babies) and killing turbos that way?

It seems like stock turbos outlast aftermarket turbos by a long shot, even when run above factory boost levels. I've personally blown two turbos, one was a billion mile k24 and one was the vnt15 on my tdi because i was running it with a bad vane actuator and it was boost spiking to insane levels without my knowledge (no boost gauge).

Should there be more consideration given to oiling, or turbo chra leveling or ???

Anyone else notice that project cars seem to eat turbos way more than they should?

I would say two things are probably happening. Aftermarket turbos are lower quality than production turbos. They have higher air flow capability, but are lower quality. And....people working on their cars are screwing things up. Reliability = 1/ number of bolts you mess with.

123quattro wrote:I would say two things are probably happening. Aftermarket turbos are lower quality than production turbos. They have higher air flow capability, but are lower quality. And....people working on their cars are screwing things up. Reliability = 1/ number of bolts you mess with.

I suppose that is another reason I like Holsets, they seems to be pretty bomb proof (albeit inefficient compared to what has come out in recent years)

I definitely understand the reliability thing vs. wrenching. But a turbo is pretty damn simple. Mount it level, provide it with good oil and drain, filter the incoming air and control the boost. Its one of the simpler devices found in an engine bay.

Spinning them way past what they're "technically" designed for?

Yeah, that too. Learn to read a compressor map. Turbos with "HP" ratings are dumb. That's a best case number based on BSFC and pressure ratio, which is a function of engine displacement. Most people with an aftermarket turbo are killing them by over speeding them or over oiling them. Another thing that's bad for them is blowing off intake hoses under boost. The turbine shaft speed goes plaid.

Spaceballs, lol

It's because they aren't holsets.

holsets and spaceballs references. This thread is relevant to my interests.

I know people going through turbo's on stock WRX/STi's. I guess VF series turbo's are junk. I was boosting 60 P.S.I on my Holset on my 95 Ram Cummins LOL! Tough sonbitch!

Bad tuning, running turbos outside of their efficiency range/designed max pressure, buying used turbos, insufficient oiling/improper restrictor, and the list goes on.

I'd say most people probably break other parts on a car before they expend the life of a turbo they bought brand new. So I'm not sure that project cars do indeed blow up more turbos. I don't think there's too many people who have tens of thousands of miles on the same turbo, usually they blow up engines first.

Uncle Helmut wrote:I know people going through turbo's on stock WRX/STi's. I guess VF series turbo's are junk. I was boosting 60 P.S.I on my Holset on my 95 Ram Cummins LOL! Tough sonbitch!

Subaru put a little screen on the oil feed to prevent any leftover manufacturing junk from getting to the turbo.

Screen plugs, turbo dies from lack of oil. New turbo dies even sooner. New turbo dies sooner than that.

Clearly your friends aren't doing any side loading, because what usually sets it off is urped rod bearings from oil starvation in corners. Often from low oil levels because Subarus have this weird thing they do where they suddenly use a half quart of oil during a 60 second run, at random, and people don't check the oil level nearly often enough. So you first blow the engine, then you replace that and the turbo dies a little while later.

It's a Subaru idiosyncracy that doesn't tolerate bad ownership.