615awhp 600awtq FP black, Need some advice

[94laserawd]

Recently dynoed my car to finalize my tune.

I was really disappointed how much the tq drops off in the upper RPM

Looking for some advise to fix this

Stock block with arp and MLS
HKS 272 cams
Stock IM
fp race manifold
FP DSM black
3" exhaust with external wastage recirculated 2.5" O2 housing
e85 at 36Psi boost
buschar racing 2.5" intercooler

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[Black95TSIawd]

You can try bigger cams and a SMIM, but you'll lose a ton of low end. Regardless, welcome to making big power on a stockish turbine housing.

 

[bastarddsm]

, that's horrible. If that thing is really making 600ft*lbs on stock rods, good luck with that....

 

[JusMX141]

...welcome to making big power a stockish turbine housing.

+1.

 

[donniekak]

Beside the turbo not lasting at that much boost, or the bottom end, it's not bad. You're making 500hp for almost 3,000 rpms with that small of a mod list.

With the same compressor, but a Garrett center section/turbine, and fp30 housing I'm getting quicker spool, and peak power not made until around 8,000 rpms. I ran a similar turbo, the fp red. The Mitsubishi style half teardrop volute housings do pretty horrible after around 30 psi, even with the heavily clipped td06h turbine.

 

[b00stedtalon2]

That's a lot of TQ for the stock block... You have a large usable powerband which is good. A large cast or SMIM doesn't usually help with TQ.

What does the boost curve look like? You could use a 3 port solenoid to control boost if you aren't already to help keep the boost from falling up top.

I wish FP had an option to run the green/red/blacks with a FP30 housing.

 

[Black95TSIawd]

I wish FP had an option to run the green/red/blacks with a FP30 housing.

Doesn't the red use a 30R comp wheel and the black a 35R? I'm not sure if the green would benefit too much with a better/larger hotside.

 

[donniekak]

I wish FP had an option to run the green/red/blacks with a FP30 housing.

The dsm76, and dsm82 would be the closest to that option. Why upgrade the turbine housing and still use a chopped up td06h turbine anyway?

It's not a good idea to run an 82mm compressor to the limit on a journal bearing center section that is based on the one the stock 14b came with anyway.

 

[94laserawd]

I use the AEM V2 to control boost. It holds 36psi very well all the way through to redline.

So pretty much the only good way to is to go t3 or t4?

Would there be anything to gain from going to an open dump wastage setup? Im trying to do the most cost effective approach, $300 for a External wastage, or about $400-$500 for a decent IM

 

[Black95TSIawd]

External should increase the power substantially by lowering your backpressure.

 

[97_4g63t]

Thats about the same power i made at 33 psi. Im on an external wg, with smim and a 2.3. Ive talked around and the black is just maxed out. You wasnt getting compressor surge?

 

[94laserawd]

Haven't experienced compressor surge yet.

 

[TalonSpeed]

Upgrading to external gate isnt going to help him. at 36psi his gate is probably only letting a little exhaust gas around the turbo.

If you want more power you need intake manifold, cams with high lift (Kelford 272, GSC S2), and upgrade the exhaust manifold good tubular unit that wont crack.

 

[TalonSpeed]

Or go the next step up and thats a HX40 in bep 55AR housing.

 

[donniekak]

Or go the next step up and thats a HX40 in bep 55AR housing.

Actually the only turbos likely to make more power, with a better powerband, in a Mitsubishi flange are the dsm82, and dsm86 from fp.

 

[97_4g63t]

Actually the only turbos likely to make more power, with a better powerband, in a Mitsubishi flange are the dsm82, and dsm86 from fp.

He knows whats up the black is maxed out. If you want more power you gotta go t3 or t4. Mhi is maxed out. You aint gonna make much more on mhi flange. You are making good power as is. Wanna make more and hold it through the range then upgrade. Personally im looking to precission because of price. Fp has upgrades as well if you want more. Changing your whole exhaust setup is the shitty part which is were im at also. 600 plus is good. Are you going for dyno queen or 1/4?

 

[mantega4g63]

Or go the next step up and thats a HX40 in bep 55AR housing.

Id say go t3 hx40 but at this point, where does op want to be? Is twin scroll t4 gt42 or BW in his options or does he want the most out of his setup? All i ever heard was dont run a mhi/fp turbo over 30psi, im not trying to say it cant be done but does op want dd or weekend warrior/garage queen? Cause i want a dd and i got a t3 hx40 and dont debate looking back

 

[Black95TSIawd]

Upgrading to external gate isnt going to help him. at 36psi his gate is probably only letting a little exhaust gas around the turbo.

If you want more power you need intake manifold, cams with high lift (Kelford 272, GSC S2), and upgrade the exhaust manifold good tubular unit that wont crack.

If his wastegate flapper is opening, then yes, it will help him. Maybe not with peak power, but it should help the power dropoff. His biggest problem right now is backpressure.

Anything he does will more than likely help with the power delivery, but saying an external won't is a bit ridiculous.

 

[TalonSpeed]

At 36psi the FP Black is past its efficiency range and is struggling to flow enough air to maintain 36psi......so the wastegate is pretty much closed or open just a little. So how would an external gate help? He is hitting his boost targets fine so the wastegate is doing its job fine.

The problem is small turbos require a lot of backpressure to make lots of boost. Backpressure can revert hot exhaust gas back into the engine during the period of cam overlap. On top of that small turbos turn into hot air guns at high boost levels. The E85 is keeping this setup running smoothly.

If the guy wants more top end but with the same turbo setup, cheapest way is to run sheet metal or evo3 intake manifold, and a tubular manifold (the extra volume inside the manifold over the FP\stock unit will lower back pressure). Next thing is cams that have high lift, not duration and a ram air intake to the turbo if possible.

I did everything above to my E16g and it pulled WAY better in the upper end. It still wasnt a high rpm screamer, the power seemed to peak then just stay flat instead of tank.

In my experience larger, free flowing, and\or dumped wastegates allow more precise control over boost, but dont create any power.

 

[TalonSpeed]

Actually the only turbos likely to make more power, with a better powerband, in a Mitsubishi flange are the dsm82, and dsm86 from fp.

A 6 blade HX40 Pro in a bep 55 housing should spool up the same but choke about 500-1000 rpms later. The DSM 76,82,and 86 are better turbos but they cost $2000 compared to a junk yard HX40.

 

[Chumpaumpalumpa]

At 36psi the FP Black is past its efficiency range and is struggling to flow enough air to maintain 36psi.....

This is exactly what's happening. It's also heating the air up a hell of a lot more and you are likely getting lots of timing pulled in the upper RPM range.

 

[94laserawd]

Ill probably just drop the boost down a little. It seems pretty tapped out.

Looking into a nice SMIM, but thats down the road. The car is mostly a weekend car setup for autoX and the local rally cross/road course.

Just wanted to see what the setup was capable of.

 

[Chumpaumpalumpa]

Ill probably just drop the boost down a little. It seems pretty tapped out.

Looking into a nice SMIM, but thats down the road. The car is mostly a weekend car setup for autoX and the local rally cross/road course.

Just wanted to see what the setup was capable of.

Well you definitely found that out. Dropping the boost should give you more power up top.

 

[JusMX141]

At 36psi the FP Black is past its efficiency range and is struggling to flow enough air to maintain 36psi......so the wastegate is pretty much closed or open just a little.

Eh, I don't necessarily agree. The HTA82, where the Black's compressor is derived from, would perform much better at the same boost level than the Black simply because of better aero tech on the turbine as well as a better-designed and higher-flowing turbine housing.

I do agree that the compressor may be nearing the end of what it can do at that boost level, but I don't think it's so far out of it's efficiency that it's struggling to keep airflow up and forcing the wastegate to close just to do so. There are other compressors in the 60mm and smaller range that have no trouble maintaining boost into the upper 30's / lower 40's. I've had a couple of HY35 users absolutely raping the 54/78mm compressor to 42-43psi and they never reported that the turbo struggled to generate airflow....in fact, they were even able to extend airflow beyond the map a little at that boost level because of extremely-efficient supporting mods that kept the air charge cool and aided in additional airflow production.


Turbine efficiency at high boost, much like compressor efficiency at high boost, has to do with the trim of the turbine. A large inducer / small exducer turbine is going to increase turbine backpressure and spool quicker because it's cupping and "funneling" the exhaust flow into a tighter space while a small inducer / large exducer is going to be much laggier but is able to handle a larger mass of turbine flow without restriction.

The GT35R turbine has a 68mm inducer, 62.3mm exducer, and 13.5mm tip height in round figures. That's a very wide inducer tip, and it's only compressing the exhaust flow 5.7mm over the entire radius of the wheel. The GT35R turbine is born to flow.

Now the TD06H4 turbine is 67.2mm on the inducer, 58.7mm on the exducer, and has an 11mm tip height. It's 2.5mm more-narrow on the leading edge of the inducer than a 35R, and the exhaust flow is being compressed 8.5mm over the radius of the wheel. FP chooses to clip the turbine on the Black to help gain a little peak flow, but you can't make a repurposed diesel turbine flow the same as a turbine that's born for performance....and in a smaller a/r housing to boot.

Even if it were possible to mount a FP35 turbine housing on a MHI-based DSM Black, the turbo still wouldn't flow as well as the DSM82 using the 35R turbine...bottom line.



The Black is an adapted turbo to fit a niche...just like a HX40 with a .55 BEP housing. It's a budget version of the DSM82 targeting HX40 users. If the Black performed the same as a DSM82 then they may as well discontinue the DSM82 since it carries a $1000-heavier price tag. If you're looking to max out the HX40 compressor, you wouldn't choose the .55 a/r BEP housing, so if you're looking to max out the HTA82 compressor it's not going to happen in an 8cm2 (roughly .55 a/r as well) MHI-copy turbine housing either.

 

[97_4g63t]

Eh, I don't necessarily agree. The HTA82, where the Black's compressor is derived from, would perform much better at the same boost level than the Black simply because of better aero tech on the turbine as well as a better-designed and higher-flowing turbine housing.

I do agree that the compressor may be nearing the end of what it can do at that boost level, but I don't think it's so far out of it's efficiency that it's struggling to keep airflow up and forcing the wastegate to close just to do so. There are other compressors in the 60mm and smaller range that have no trouble maintaining boost into the upper 30's / lower 40's. I've had a coupler HY35 users absolutely raping the 54/78mm compressor to 42-43psi and they never reported that the turbo struggled to generate airflow....in fact, they were even able to extend airflow beyond the map a little at that boost level because of extremely-efficient supporting mods that kept the air charge cool and aided in additional airflow production.


Turbine efficiency at high boost, much like compressor efficiency at high boost, has to do with the trim of the turbine. A large inducer / small exducer turbine is going to increase turbine backpressure and spool quicker because it's "funneling" the airflow into a tighter space while a small inducer / large exducer is going to be much laggier but is able to handle a larger mass of turbine flow without restriction.

The GT35R turbine has a 68mm inducer, 62.3mm exducer, and 13.5mm tip height in round figures. That's a very wide inducer tip, and it's only compressing the exhaust flow 5.7mm over the entire radius of the wheel. The GT35R turbine is born to flow.

Now the TD06H4 turbine is 67.2mm on the inducer, 58.7mm on the exducer, and has an 11mm tip height. It's 2.5mm more-narrow on the leading edge of the inducer than a 35R, and the exhaust flow is being compressed 8.5mm over the radius of the wheel. FP chooses to clip the turbine on the Black to help gain a little peak flow, but you can't make a repurposed diesel turbine flow the same as a turbine that's born for performance....and in a smaller a/r housing to boot.

Even if it were possible to mount a FP35 turbine housing on a MHI-based DSM Black, the turbo still wouldn't flow as well as the DSM82 using the 35R turbine...bottom line.



The Black is an adapted turbo to fit a niche...just like a HX40 with a .55 BEP housing. It's a budget version of the DSM82 targeting HX40 users. If the Black performed the same as a DSM82 then they may as well discontinue the DSM82 since it carries a $1000-heavier price tag. If you're looking to max out the HX40 compressor, you wouldn't choose the .55 a/r BEP housing, so if you're looking to max out the HTA82 compressor it's not going to happen in an 8cm2 (roughly .55 a/r as well) MHI-copy turbine housing either.

So all in all the compressor is not maxed out just it's turbine housing is too small. It's too much compressor for 8cm2 turbine housing. So maxed out would be a bad way of saying it. Efficiency is greatly suffering from the smaller turbine housing but more power can be made or it would be safe to say that the turbine housing is maxed out?