Anyone blow a stock engine running 8 psi(<300HP)
 

As title states, has anyone blown a stock engine running a conservative 8 psi tune with less than 300 hp? if you did was it due to the tune or the engine internals just gave up? I searched but only found threads dating to the earlier years of the twins and people mostly seemed to have issues with tunes or really pushing the engine past 350hp

Anyone who has a simple turbo setup with low psi and <300 hp, how has the engine managed and has anyone have over 50k boosted at this low power level?

Thank you guys very much for your input!!!

I bent a rod at 7psi with a bull blown stage one kit.

But it can happen to anyone honestly. I have a friend making 400 on stock block 14psi


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Was it due to boost creep? Or good tune everything good just blew?

Everything was going good and there it went


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what year was your car? brz or frs? that's crazy man kinda scares me into an NA build lol

What kind of FI installation? What brand? What were the conditions when it failed?

Lmfao 13 frs full blown stage one with GTX28 didn’t even have 30k on the car. After I bent the rod I took engine apart and built it. when I went to start I found out why I bent a rod and it turned out that I had a direct fuel injector staying stuck open at times

Woahh man that's a huge bummer, it wasn't even the power you were pushing but just a malfunction damn. Do you think that it had something to do with the tune?

No it was a mechanical failure in the injector. Took them to get flow tested and the one that bent the rod was stuck open pretty bad. James even told me that was the first direct injector he ever saw stay stuck open. Coming from him that he’s tuned a lot of these cars means it’s really not common at all

Does it have to be specifically 8psi?

If you cannot afford to replace an engine, do not go FI. yes, people get lucky. More people get unlucky. There's a reason more cars in the world don't just get a turbo slapped on them: the cost of entry into the carnival is the cheapest part of the endeavor.

Boost for the most part is irrelevant. Knock, af/r, supporting mods, the tune, not making a ton of wtq low in the rpm bands are things that contribute to survival chances if TUNED correctly. If you don't have catch cans and oil enters your intake, you get knock; oil lowers your octane significantly. Oil supply is tied to rpm; low rpm high load conditions mean the weak rods sustain more load for longer.

This is the surface of theories, rumors, facts, and things you need to consider when you think you'll take a coin flip and go turbo.

Not really just low power , I've heard everywhere that pushing past 300 is asking for trouble and I'm looking to stay below that

Definitely agree with the idea of if you can't replace it, don't go turbo but after extensive research I've came to the same conclusion you have, Oil cooler or an AOS/catch can, AEM wideband, gauges and a good tune will give you a reliable boosted FA20, I plan on boosting to the power levels of a carb legal edelbrock (~270hp ~210wtq) which have proven to be safe on the internals. I want to see how common it is to blow an engine at these power levels

I agree with you that it all comes down to how well you maintain the turbo and how much thought you put into the lines and cooling and tune.

Yeah the D4S system is supposed to be the best. I've heard a lot from James at HRI that he does some great tuning and hes local for me here in florida, are you still running a tune from him or a turbo kit?

Depends where you make the 300.

You mean in the powerband where it peaks? Are certain RPMS more dangerous or something??

300 hp a peak rpm is a lot less hazardous than 300 hp at 4000rpm.

Yup still boosted just now I’m built and boosted. And yes still have his tune, where are you located in Florida? I’m in Miami

I see exactly what you are saying and thanks for that info man, I can relay this info to whoever tunes it so it's a little more conservative

I'm in Tampa, I wish I could see someone with a turbo kit here

I ran 360ish 274 TQ E85 on 11psi
I had it for about a year. No issues at all.
JRSC C38

Go the Cars, Coffee and Karting over in Brandon. It's one Saturday morning a month, at the Tampa Bay Grand Prix. There's alsways a couple turbo twins over there.

OH BOY THANK YOU SO MUCH FOR THE LIGHT I HAVE BEEN LOOKING SO HARD FOR A MEET!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I'm gunna be there June 9th to see if I can see any turbo twin

Boosted at 8.6 psi with AVO 1.5 Kit for the last 5 years/40k. Mine was one of the first AVO kits in the country. The car is still producing precisely what it did in 2013. 270hp + 212tq. NOT ONE ISSUE!

Drift Office - Best place in the country to get your FA motor tuned. Nuff said.

Hbp pulley?

one thing to mention that hasn't been so far is exhaust back pressure

the stock system is quite restrictive and going up to a minimum of 2.5" if not 2.75 to 3" really pays dividends and will help with the motor life as less back pressure means its more resistant to knock and less knock events = a happier motor

Yes.

People should comment whether they track the car or not. I have no doubts in my mind that you can keep a low power FI setup (sub 300 whp) alive for maybe the life of the car *if* the car is only a street car. That same setup might only last a few track days with a fast driver.

Holy zombie thread

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At least the reply was from someone who had been asked a question, and not someone asking an additional stupid question of someone who hadn't been on since 2014

Assuming oil or fuel starvation has been addressed and that cooling has been addressed, are you suggesting track conditions will cause someone to fatigue out the rods or that someone will downshift aggressively enough to increase forces or that stickier tires on a track will increase the load too much to snap rods?

I haven’t tracked my car, but I routinely take the car to redline. I’m on E85 at a bar of boost on a Harrop SC, Ace150 and Michelin Pilot Sport 4Ss. No issues so far.

I always wonder if the issues that lead to motor failures are more about other issues than power in those track situations like not using E85, not properly lubricating or cooling the car or some type of starvation issue. It would be nice to know for sure when a failure happens.

I your car is tuned properly fuel does not play a role. Unless you get bad gas.

Knock resistance, keeping the combustion chamber/oil/engine cooler, less boost needed for the same power output, less variability in power depending on the ambient air temps means more consistency.

Were you making a point that I missed?

It's too complex IMHO. We humans like to simplify things but in this case don't think it's simple, too many variables and combination of those variables can lead to a failure.



Forget all these commonly addressed factors like heat management, knock resistance, driving habits, etc. Consider basic variance in motor construction - high volume 'cheap' motors typically have a fair amount of variance that is acceptable within the intended design envelope. You can get away with it if your motor has to manage a peak of 160 whp and 130 wtq - "get away with it" meaning they can produce a motor at specific planned cost without having a ton of stock failures/warranty claims.



Now, double the torque and hp output - you're way outside that design envelope. Any weaknesses/flaws in your particular motor will quickly be made apparent - given most manufacturing is relatively consistent and most motors will manage fine, but any variance/weakness will very quickly become apparent.


Once that happens we all try to point fingers at the obvious things, but we all have to keep in mind that pushing a motor way past its original parameters is a game of russian roulette to some extent.

In my eyes, here are a few reasons that track work is so mechanically stressing on vehicles compared to street use:

1. Higher oil temperatures from sustained high rpm's could lead to early bearing failures and pre-mature component wear as the oil becomes less viscous with temperature increase.

2. Heat soak from high load, high rpm use increases the IAT's. More so, when you are in traffic on track you are not able to get clean air. Higher IAT's/charge temperatures mean increased chances of knock, detonation or LSPI.

3. Depending on track layout, you may be forced to run the car in conditions that you wouldn't normally find on the street. Example: There's sections of tracks that are up steep hills (Laguna Seca for example), which see's long WOT's up hill. This is a scenario where you will be loading the engine (almost lugging) far greater than on the street. Another example is there's a local track that has you between 6800-7400 rpm on and off WOT for like 15 seconds. On the street, it would be very odd to hold 6,800+ rpm for that long.

Have you been on track before? It's hard to fathom how hard track work is on a vehicle if you haven't experienced it. Doing a 10 second pull on the street is one thing, but a car can see 15-20 minutes+ of sustained WOT at high engine speeds during a single session. There's a reason why some motorsport dampers can go 100K street miles without a rebuild, yet recommend a rebuild after 20-30 track hours. It's just simply magnitudes harder on components.

You specifically mention not using E85 as a reason that may cause a blown engine.

What I am getting at is that what fuel you run should be what fuel you are tuned for and has absolutely no bearing on blowing an engine.
Having E85 is nice but not always available.

Knock resistance - Tune for less timing based on what fuel you run.

Less boost needed for the same power output - Shouldn't be tuned for more boost/power than you can safely get with your fuel anyway.

The way your argument is worded comes to the logical conclusion that everyone should run full on race gas.

Haven’t. Just the canyons n street. Never made time for the track.

Yeah, I blew a rod bearing with my Spintex SC pushing 8-10 psi (75mm pulley) and e85 was used exclusively. It took 3-1/2 years to reach failure. So I don't think the tune was at fault at all. Car has been sitting in the garage since September. I will be getting it in the shop in January though. New Manley forged rods going in with new King XPG main and rod bearings and a new stock crank shaft. I don't intend to generate more than 300 -320 hp at the wheels. However, I will ask since I can't find the information online. How much HP can the stock pistons handle before they disintegrate??? 120 hp per piston, 150 hp per piston ?? More?? Less?? If anyone knows please post the information for me. I'd like to get a set of forged JE Pistons at 12.5:1 stock compression, but not if the stock pistons can actually handle at least 400 BHP or more. I'm not looking to make crazy power for my daily driver.

As other have said don't boost unless your prepared to drop another or built engine in. Hell people have spun a rod/bearing in NA cars on the track.

If only 2 choices, which one would have less knock events?
1) Catless header + OP + high flow cat front pipe but with stock exhaust?
2) 2.5" Cat-back only

Trying to minimize the noise but want to have less back pressure to have less knock events.

Thanks!