MHI FP 20g problems

stevenr816

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Figured I would post on here to see what feedback you guys have. Its not on my supra its on my DD dsm.

Previous setup was a small 16g td05 exhaust wheel/housing, 21psi, for 6-8 months.
New setup, 20g td05 exhaust wheel/housing, 21psi, 2 days

I bought it off of ebay, its a legit FP 20g off a subraru with a broken td06 exhaust blade. So swapped my td05 exhaust wheel into it to keep my same wastegate setup. Had the 20g wheel and td05 exhaust shaft balanced, and rebuilt it with a new kit.

Ever since this turbo, the exhaust has had a really loud spool/whine sound with the same exhaust setup. Click on this video for sound (this is how the first turbo build sounded) http://www.youtube.com/watch?v=xEmsrF66Fa8=

1st build ended up lasting 2 days until it started whining badly. Compressor bearing was toast, exhaust was perfect. Figured this was from oil starvation cause I put a banjo bolt on the oil feed and didnt notice the inlet was half the size of the stock and only had 1 outlet hole instead of 2.

Rebuilt the turbo again, rebalanced. Drilled and taped my head and cartridge to accept 1/8npt to -4an lines. (Impossible to find 12x1.25 to -4 fittings local) This time it lasted 3 days with some decent races at the local supra meet. Exhaust bearing toast. Figured it was from contamination cause there was a piece of thread in the thrust washer passage. (keep in mind i started the car and let it run for 30 seconds draining the feed into a cup to clean the new threads i taped, aswell as cleaning the cartridge before install.)

Rebuilt it for the 3rd time, new bearings, new thrust, new rings, new balance, primed for about 2 minutes. Lasted 2 pulls and dead, wont boost past 5 psi. Havent taken it apart to see which bearing it is.


Any ideas? The only thing that has changed is the cartridge, compressor wheel and housing. Same exhaust setup as before. I am changing the cartridge to the previous one/machining the exducer bore larger to fit the wheel to see if that changes anything.
 

MDCmotorsports

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If you're sure it's not an oil feed issue from the engine, I can tell you 100% right now its the balance.

Mitsu turbos and the small frames as such (IHI, Mitsu, Garrett) are impossible to hand balance as you have described. I've had rotating assemblies balanced to minuscule amounts before, only to blow up on me because of harmonics coming back through the housings.

They MUST be vibration sort rig (VSR) balanced or component balanced with OEM tolerances. That includes the nut on the end of the shaft. I doubt FP is using a threaded comp wheel.

Check your oil feed coming out of the block for shits and giggles.

You'll want to check to make sure the bearing housing is straight, and not over bore. You'll also want to make sure the surface of the bearing housing internally isn't egg shaped and or coarse. The surface needs to be N1-N5.
 

hvyman

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Why didnt you just run run stock 20g?

Mdc knows turbos and i wont go against his info but it seems like you mismatched a turbo.

Also it seems lije you were trying to keep the same exhaust wheel inorder to keep the same tune?

When switching from 16g to 20g you need to retune.

There should be no benefit from using a smaller frame turbos exhaust wheel on a larger frame turbo. I am lost at why you did this.
 

stevenr816

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hvyman;1667124 said:
Why didnt you just run run stock 20g?

Mdc knows turbos and i wont go against his info but it seems like you mismatched a turbo.

Also it seems lije you were trying to keep the same exhaust wheel inorder to keep the same tune?

When switching from 16g to 20g you need to retune.

There should be no benefit from using a smaller frame turbos exhaust wheel on a larger frame turbo. I am lost at why you did this.

I got the FP one cause I found it on eBay off a subaru with a blown exhaust wheel for $80 is what the bid went to. It's a $500 turbo. SO that's why I ended up with a FP. Only difference is a bigger wastegate flap and bored out.

I kept the stock wheel and housing to keep my exhaust setup and external dump. They make TD05 and TD06 20gs so thats not a problem. Far from trying to keep the same tune. I have DSM link and a full palm data logger.

I have ordered the TD06 turbine and scroll waiting for it to come in. The one of the Subaru was different bolt patterns

---------- Post added at 05:25 PM ---------- Previous post was at 05:20 PM ----------

MDCmotorsports;1667110 said:
If you're sure it's not an oil feed issue from the engine, I can tell you 100% right now its the balance.

Mitsu turbos and the small frames as such (IHI, Mitsu, Garrett) are impossible to hand balance as you have described. I've had rotating assemblies balanced to minuscule amounts before, only to blow up on me because of harmonics coming back through the housings.

They MUST be vibration sort rig (VSR) balanced or component balanced with OEM tolerances. That includes the nut on the end of the shaft. I doubt FP is using a threaded comp wheel.

Check your oil feed coming out of the block for shits and giggles.

You'll want to check to make sure the bearing housing is straight, and not over bore. You'll also want to make sure the surface of the bearing housing internally isn't egg shaped and or coarse. The surface needs to be N1-N5.
Every time ive had it balance I've taken it to my local turbo guy that I've used for years to balance turbos without a problem. Dont know what type of balancer it is. He balances them as an assembly, scribes a line on the nut, wheel and shank.

I'm putting my original center housing on as I type. I just machined it out to the bigger exducer bore. So now the only difference is the compressor wheel and housing.
 

MDCmotorsports

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stevenr816;1667388 said:
Every time ive had it balance I've taken it to my local turbo guy that I've used for years to balance turbos without a problem. Dont know what type of balancer it is. He balances them as an assembly, scribes a line on the nut, wheel and shank.

Yes. That is static balancing, or some call it a "rotating assembly balance."
You can doubt me all you want, but you will not get the turbo charger to run properly with that balance. The unit HAS to be VSR balanced or no dice. The only other way around it is to balance each of the parts individually to OEM specifications. I doubt your turbo guy has CNC grinding & balancing capabilities....
 

stevenr816

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Never said I didnt believe you?
Only thing I'm concerned about is how I've used him on some 30 odd turbo balancing (ct26, some garretts and borg Warner) and still run to this day. But the one I rebuild for my own car can't stay together worth crap.
 

MDCmotorsports

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stevenr816;1667533 said:
Never said I didnt believe you?
Only thing I'm concerned about is how I've used him on some 30 odd turbo balancing (ct26, some garretts and borg Warner) and still run to this day. But the one I rebuild for my own car can't stay together worth crap.

Dollars to doughnuts he's using a Heins balancing system. That system can not compensate for a hybrid setup (compressor wheel VS turbine).

This most likely is the problem.
 

IJ.

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stevenr816;1667388 said:
I got the FP one cause I found it on eBay off a subaru with a blown exhaust wheel for $80 is what the bid went to. It's a $500 turbo. SO that's why I ended up with a FP. Only difference is a bigger wastegate flap and bored out.

I kept the stock wheel and housing to keep my exhaust setup and external dump. They make TD05 and TD06 20gs so thats not a problem. Far from trying to keep the same tune. I have DSM link and a full palm data logger.

I have ordered the TD06 turbine and scroll waiting for it to come in. The one of the Subaru was different bolt patterns

---------- Post added at 05:25 PM ---------- Previous post was at 05:20 PM ----------


Every time ive had it balance I've taken it to my local turbo guy that I've used for years to balance turbos without a problem. Dont know what type of balancer it is. He balances them as an assembly, scribes a line on the nut, wheel and shank.

I'm putting my original center housing on as I type. I just machined it out to the bigger exducer bore. So now the only difference is the compressor wheel and housing.

That there scares the fuck out of me.... :nono:
 

MDCmotorsports

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stevenr816;1668096 said:
Everywhere ive called locally they all have the heins

Your best bet then is to have the turbine balanced and then the compressor wheel balanced.

You're still dealing with an unbalance issue when / if you used the old nut or even a new one.

Heins systems are great for stock matchup parts. A 57 trim to4e wheel with a p trim turbine for example. For what you're doing though, no dice man.
 

stevenr816

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Sadly have to bring this thread back up. Since the last rebuild it finally let go last night. So this one lasted 1 month. No warning until it started rubbing the housing. Shaft has no discoloration either.

Anyone think that hooking the coolant up to the cartridge would save turbine side bearings? Compressor bearing is perfect, turbine bearing is completely gone (.075" of play on the tip of the shaft) also the turbine ring is grooved. Shows signs of back pressure. Theres no way I have post turbo back pressure on this turbo with 3" straight piping & 2 90* bends. Pre turbo back pressure is another story probably.

I will still check post turbo back pressure tonight have an extra bung so going to drill and tap it for a brass fitting.

Anyone have any ideas? BOV? Pre turbo back pressure? Compressor surge? Boost? Oil break down?
 
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MDCmotorsports

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Have you listened to nothing I have said or typed? Really? You think I hit these plastic buttons for fun? And no, the water cooling will do nothing to solve the problem you're having.
 

MDCmotorsports

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Yes. Sounds like you'll need that bearing housing rebuilt or a new one now though.
I believe you have been chasing a balancing problem all the while now. Even more so now that you stated you have seen eveidence of thrust comingfrom the turbing.

---------- Post added at 11:37 PM ---------- Previous post was at 11:37 PM ----------

Yes. Sounds like you'll need that bearing housing rebuilt or a new one now though.
I believe you have been chasing a balancing problem all the while now. Even more so now that you stated you have seen eveidence of thrust comingfrom the turbing.
 

stevenr816

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MDCmotorsports;1683556 said:
Yes. Sounds like you'll need that bearing housing rebuilt or a new one now though.
I believe you have been chasing a balancing problem all the while now. Even more so now that you stated you have seen eveidence of thrust comingfrom the turbing.

---------- Post added at 11:37 PM ---------- Previous post was at 11:37 PM ----------

Yes. Sounds like you'll need that bearing housing rebuilt or a new one now though.
I believe you have been chasing a balancing problem all the while now. Even more so now that you stated you have seen eveidence of thrust comingfrom the turbing.
This last one I got rebuilt, I had Forced Performance rebuild it (the manufacture of the turbo/upgrader) everything was in spec (cartridge bore, ring gaps, etc) , cartridge was straight. They only have a Hanes as well.

It lasted 2 days and same thing.
Something isn't right I think I'm going to get a new/known working center cartridge and machine it for the exducer and go from there. I might just upgrade it to a new TD06 shaft, and get the 60-1 compressor conversion for all new parts.

I have both ports tapped for pre turbo and post turbo back pressure. Haven't hooked my gauges up yet

I have the motor pulled out cause I'm throwing everything into an AWD shell I got so have time to figure stuff out.