Looking for opinions

[tysparks81]

Hey LGT squad,

 

I'm looking for opinions and possible places to look, before I start falling down another rabbit hole.

 

I recently had a motor built. Just finished my break-in mileage, and put the car on the dyno for a very unimpressive 263whp/259wtq.

Which doesn't make much sense since a stock vf52 should make in or around 300whp/290wtq. The turner is saying that there is something wrong with the turbo(10-15k since rebuild) its hitting 19psi, but not making the right

power if that makes sense.

 

 

Happy to send logs if that would help. My next step would be to throw on a stock vf52 and go for a retune.

 

Closed deck block with 99.75 forged pistons, rods

built heads with GSC stage 2 cams

Parallel fuel Top Feed fuel lines with FPR

1000cc injectors

dw300c

TGV deletes

HKS intake

GS 3port ebcs

catted downpipe to muffler deletes

custom 11blade vf52

[Max Capacity]

FWIW, here's my sheet, vf52 on stock fueling, Invidia up/dp

 

 

 

 

You might want to reach out to tuningalliance@gmail.com and ask Mike what he would charge to help you figure it out or send you a good tune.

[boxkita]

looks like tuner was trying to you driveable torque instead of max torque.

[awfulwaffle]

That seems very low on a VF52 based on what I've seen as well. In order for that to be the case, your compressor would have to be way off-island on the flow/efficiency map, meaning you're making target pressure at a much lower density (higher temperature). If the turbo itself is fine, this would imply a significant post-turbo air leak in my book or some other parasitic loss that's causing the compressor to work way harder than it should be.

 

The other option is a pretty nasty aero issue somewhere in the compression section of the turbo. Meaning, bad flowpaths on either the wheel or compressor cover, whether due to damage or manufacturing issues. This would drive up losses and effectively mean you're operating on a different (and crappier) map than the VF52 should be. Were quality parts used in the rebuild, and is there any visible damage anywhere?

[dgoodhue]

Was this turbo on your car previously? or did you buy it used and this is the 1st time using it?

[norutah]

looks like tuner was trying to you driveable torque instead of max torque.

X2, I have a 52 with gobs of torque and on outback gearing 1st and 2nd are virtually worthless if you are too generous on the throttle. It was fun at first but going to change it up a bit. You can run through 1 and 2 responsibility or spank the rev limiter. No happy medium

 

Sent from my HD1925 using Tapatalk

[tysparks81]

FWIW, here's my sheet, vf52 on stock fueling, Invidia up/dp

 

 

[ATTACH]292298[/ATTACH]

 

 

You might want to reach out to tuningalliance@gmail.com and ask Mike what he would charge to help you figure it out or send you a good tune.

 

Haven’t been able to get anyone in the states willing to tune me due to tgv & airpump deletes. I’ll email him again and ask him if he is willing to look into this for me.

 

looks like tuner was trying to you driveable torque instead of max torque.

 

Tuner said car was making power like a 2L, and that he could add timing but it wasn’t the right way to make power.

 

That seems very low on a VF52 based on what I've seen as well. In order for that to be the case, your compressor would have to be way off-island on the flow/efficiency map, meaning you're making target pressure at a much lower density (higher temperature). If the turbo itself is fine, this would imply a significant post-turbo air leak in my book or some other parasitic loss that's causing the compressor to work way harder than it should be.

 

The other option is a pretty nasty aero issue somewhere in the compression section of the turbo. Meaning, bad flowpaths on either the wheel or compressor cover, whether due to damage or manufacturing issues. This would drive up losses and effectively mean you're operating on a different (and crappier) map than the VF52 should be. Were quality parts used in the rebuild, and is there any visible damage anywhere?

 

No visible damage when it was out a few weeks ago and it seems to be built correctly as it’s a pretty fresh rebuild from JMP(10-15k)no in/out or side to side play at all when checked and no leaks from it.

 

Was this turbo on your car previously? or did you buy it used and this is the 1st time using it?

 

Yup turbo was on the car previously I had it rebuilt before using it.

 

X2, I have a 52 with gobs of torque and on outback gearing 1st and 2nd are virtually worthless if you are too generous on the throttle. It was fun at first but going to change it up a bit. You can run through 1 and 2 responsibility or spank the rev limiter. No happy medium

 

Sent from my HD1925 using Tapatalk

 

So I have a stock vf52 I was going to consider putting on but wasn’t sure if it was my tuner or something with my car.

[boxkita]

check all your connections for any leaks? Boost graph seems slow to rise & low.

Sgt.Gator has "Murray" constant tension clamps that help maintain clamping pressure. I forget actual name, but race wagon was full of them. I had to use one on the race mustang to keep an adequate seal on the intake manifold.

 

check all your grounds? a beefy ground everywhere (especially with tgv deletes) will improve

runnability. . Did you do the fuel pump wiring upgrade recommended by underdog?

 

are you sure the fuel pump is providing enough fuel?

 

injectors providing adequate pressure & volume?

 

still if tuner says turbo issue, I'd ask for more details then contact jmp with details and ask for help. if its been 15k since rebuild, turbo might need a touchup.

 

I'd still do a thorough check of connections before spending money. Kip & I both experienced track-related failures when a silicone pipe clamp came loose. stuff happens.

Edited June 30, 2021 by boxkita
thanks awfulwaffle

[awfulwaffle]

Murray clamps, I bet

[shralp]

Huge fan of the Murray Constant Tension Clamps as well. Have swapped them in where needed in the track car. Can’t say it’s a boost leak from here but I’ll eat my hat if it’s a bum rebuild from JMP

[tysparks81]

check all your connections for any leaks? Boost graph seems slow to rise & low.

Sgt.Gator has "Murray" constant tension clamps that help maintain clamping pressure. I forget actual name, but race wagon was full of them. I had to use one on the race mustang to keep an adequate seal on the intake manifold.

 

check all your grounds? a beefy ground everywhere (especially with tgv deletes) will improve

runnability. . Did you do the fuel pump wiring upgrade recommended by underdog?

 

are you sure the fuel pump is providing enough fuel?

 

injectors providing adequate pressure & volume?

 

still if tuner says turbo issue, I'd ask for more details then contact jmp with details and ask for help. if its been 15k since rebuild, turbo might need a touchup.

 

I'd still do a thorough check of connections before spending money. Kip & I both experienced track-related failures when a silicone pipe clamp came loose. stuff happens.

 

I'm going to do a once over on all the hoses and clamps, and I will add a grounding kit.

 

Injectors seem fine based on the air/fuel, and pump was working but not over working based on duty cycle its a dw300c.. But I may do the Hardwire to it to make sure its not an issue.

 

Turner couldn't give me much more details other than showing me a stock vf52's numbers he made on near stock fueling, but I will ask him again.

 

Thanks for all the help and suggestions, doesn't seem right. We did do a smoke test and everything was sealed up tight no smoke but maybe we missed something before the tune.

[boxkita]

if you bot a custom turbo, what was custom? because that will change the compressor map. if the tuner doesn't account for that, the tune will be off.

 

maybe its designed for mote low end torque than up top.

 

also stock doesn't mean anything likewise near stock fueling

[tysparks81]

Well the turbo was a custom 11 blade wheel from JMP, not sure how the turner needs to account for that he was asking me the size of the wheel but I didn't have it to give him and JMP couldn't remember the size of it either.

 

And that could be the case as well, it does pull past redline but just not making any torque really, but that could also be due to my cams moving the power band further to the Right.

 

when I said near stock it was running stock injectors and an upgraded fuel pump with a VF52.

[shralp]

Hey ty,

 

Here is my Outback XT 5MT stg. 2 set up with JMP 11blade VF-52 on stock injectors / pump for reference if that helps any for comparison. The pdf should open bigger for you

JMP VF52.PDF

Edited July 6, 2021 by shralp

[dgoodhue]

Well the turbo was a custom 11 blade wheel from JMP, not sure how the turner needs to account for that he was asking me the size of the wheel but I didn't have it to give him and JMP couldn't remember the size of it either.

 

I didn't realize that JMP did the turbo. I have seen 'Custom Turbo' that people have sourced from ebay (ie Asia) that don't make the HP and torque one would expect.

 

Cams can make some difference, but I would not expect it shift the power that drastically to the right without seeing peak gains on the top end. You're not seeing torque or HP gains.

 

I would expect is it mechanical issue or tuner issue.

[m sprank]

Would need to see logs. But I suspect the tuner is not familiar or experienced and maybe you should be looking for a better tuner.

 

 

 

At a minimum, what is your timing at when you hit peak boost at WOT during a 3rd gear pull?

[tysparks81]

I didn't realize that JMP did the turbo. I have seen 'Custom Turbo' that people have sourced from ebay (ie Asia) that don't make the HP and torque one would expect.

 

Cams can make some difference, but I would not expect it shift the power that drastically to the right without seeing peak gains on the top end. You're not seeing torque or HP gains.

 

I would expect is it mechanical issue or tuner issue.

 

Yea I am leaning towards Tuner, but I'm not quite sure what I can tell him to do or look at, or what mechanically to look at since its a new motor build and seems to be running ok other than being down in power.

[tysparks81]

Would need to see logs. But I suspect the tuner is not familiar or experienced and maybe you should be looking for a better tuner.

 

 

 

At a minimum, what is your timing at when you hit peak boost at WOT during a 3rd gear pull?

 

Logs I could get you. Tuner did said he could add timing but didn't want to use that to make more power when it was on the dyno.

 

Not sure if you willing to do an etune on my setup but I'm leaning towards tuner since, I also have hesitation/ intermittent bogging between 1k -2.5k

[dgoodhue]

Timing can make difference depending on how conservative it is. One of my non Suabru vehicle, at the track I went from 12.3@111 to 11.9@115 from adding 4 degrees of timing and very minor changes in fueling. On my '12 Legacy GT my DAM dropped to 0.875 just as I was driving to the staging lanes. I made a run with it and then reset to the DAM to 1 and I gained .2 and 2mph. Remarkably, my 60's, launch & shifts points happened to be almost exactly the same on those 2 runs.

[BrandonspecB]

What fuel? Pump gas? If it's under timed a couple degrees would get you to your expected power. But I can't say for sure cause I wasn't seeing what the knock sensor was telling me or seeing how much power was being gained per degree of advance.

 

If you trust it's safe go do a third gear pull and post the log.

[m sprank]

My shop is long closed and no longer offer any professional tuning services. But I am willing to offer advice.

 

 

 

If you need an e-tune I would hit up Dave (Cryotune) as he has been a long time forum member and vendor. He has lots of positive reviews from this forum.