New Turbo Kit Sneak Peek(Ptuning)

[Sportsguy83]

Originally Posted by ptuning

Having lived in CA and FL, I have to say that CA weather is so much better (no humidity), but then again, owning a modded car there is definitely a nightmare.

Hey hey!!

JK!! Awesome kit!!

[scraejtp]

Originally Posted by ptuning

We would recommend the stock header for low boost pump gas tunes, probably around 6-9 psi. At these power levels, still in the low 300's, we don't foresee problems. We're aware of someone having problems with the stock header on a built engine running 18+ psi of boost. This, however, is not something that we'd recommend, hence our co-development of a 4-1 header.

Also, making sure that the tune is good (not too rich for instance), right off the bat, would be ideal.

Do you have logs of IAT on the street or dyno pulls? I'm curious as your intercooler looks quite a bit smaller than another big power kit.

[ptuning]

Originally Posted by Sportsguy83

Hey hey!!

JK!! Awesome kit!!

Apologies to the FL folks.

Thanks. FWIW, if I ever moved to FL, it'd be Miami. I somehow recall it being less humid there than the Central Atlantic coastline of FL and the beaches are awesome! No state income tax and laid back car and motorcycle laws are a definite bonus too!

[ptuning]

Originally Posted by scraejtp

Do you have logs of IAT on the street or dyno pulls? I'm curious as your intercooler looks quite a bit smaller than another big power kit.

We haven't paid too much attention to it, but we can look at the logs tomorrow. It will likely be very low, since the intercooler core remains totally cool to the touch during back to back dyno pulls, even at 400whp.

Also, we use the widest core available and the tallest practical height too. There is absolutely no bumper notching required here though.

Lastly, we use the top of the line Garrett GT core, which offers the best intercooling for a given core size.

[ptuning]

Another alternate view.

[Calum]

I'm confused, not that it's hard, but still. Why do all your dynos show 200 ftlbs of torque right up until 4400 rpm and from there MORE. I've asked before and was told it was a tuning issue, that the maps were incomplete, but that just doesn't make sense if it's still there. I'm basing this on the assumption that you guys know what you're doing, and from the reviews I've read, I think it's a safe assumption. So, either your kit is just that free flowing that before the turbo spools, you've found another 40-50 ftlbs, or the turbo is spooling that low and I've no idea why the torque climbs so rapidly.

[ecko04]

Originally Posted by Calum

I'm confused, not that it's hard, but still. Why do all your dynos show 200 ftlbs of torque right up until 4400 rpm and from there MORE. I've asked before and was told it was a tuning issue, that the maps were incomplete, but that just doesn't make sense if it's still there. I'm basing this on the assumption that you guys know what you're doing, and from the reviews I've read, I think it's a safe assumption. So, either your kit is just that free flowing that before the turbo spools, you've found another 40-50 ftlbs, or the turbo is spooling that low and I've no idea why the torque climbs so rapidly.

What are you reading? The graph above shows 200 ft/lb @ 2800RPM and goes up from there.

[Calum]

Originally Posted by ecko04

What are you reading? The graph above shows 200 ft/lb @ 2800RPM and goes up from there.

Each graph starts out at about 2000 rpm, quickly raises to 200 ftlbs as the motor goes from closed throttle to open throttle, then the torque levels off, at 4400 rpm starts to rise again toward peak. I'm questioning why the sharp rise is there at 4400 rpm, instead of being a smooth climb. If they're making 40-50 ftlbs more then stock at that low rpm range I'm guessing the turbo is spooled and should react fairly linearly throughout the rpm range. Or, perhaps it's not spool, in which case where did the extra torques come from before the turbo gets up to speed?

[ptuning]

Originally Posted by Calum

Each graph starts out at about 2000 rpm, quickly raises to 200 ftlbs as the motor goes from closed throttle to open throttle, then the torque levels off, at 4400 rpm starts to rise again toward peak. I'm questioning why the sharp rise is there at 4400 rpm, instead of being a smooth climb. If they're making 40-50 ftlbs more then stock at that low rpm range I'm guessing the turbo is spooled and should react fairly linearly throughout the rpm range. Or, perhaps it's not spool, in which case where did the extra torques come from before the turbo gets up to speed?

Most factory turbocharged cars will use very small turbos that will show full boost within a few hundred rpms. The FR-S, due to it's poor VE in the 3.5K to 4.5K range produces a boost curve that has a shallower slope than most cars we've developed turbo systems for.

Even though you see 6 psi on spring pressure at 3,500 rpms, you may not see 16 psi until 4,800 rpms. Just remember that an NA engine's VE shortcomings will not completely disappear when boosted. Only a tiny turbo will solve this problem.

The reason you may not have noticed this before is because we're seeing seeing dyno graphs that start at 4K rpms, some at 5K rpms, some with the right column torque scaling that is lower than the left column hp scaling, and some graphs with no scaling at all.

Just remember, if torque and HP don't cross-over at 5252 rpms, take a closer look at the numbers.

[carbonBLUE]

Originally Posted by ptuning

Most factory turbocharged cars will use very small turbos that will show full boost within a few hundred rpms. The FR-S, due to it's poor VE in the 3.5K to 4.5K range produces a boost curve that has a shallower slope than most cars we've developed turbo systems for.

Even though you see 6 psi on spring pressure at 3,500 rpms, you may not see 16 psi until 4,800 rpms. Just remember that an NA engine's VE shortcomings will not completely disappear when boosted. Only a tiny turbo will solve this problem.

The reason you may not have noticed this before is because we're seeing seeing dyno graphs that start at 4K rpms, some at 5K rpms, some with the right column torque scaling that is lower than the left column hp scaling, and some graphs with no scaling at all.

Just remember, if torque and HP don't cross-over at 5252 rpms, take a closer look at the numbers.

this is correct, what headers have yall tested with your kit?

resonance and restriction play big roles in the "dip" we all see. Part of which on the stock headers, is purposely implemented to create more back pressure during that rpm range for better mileage and allows us to rev into that range without taking a huge hit on mpgs during spirited driving.

[SnapOv3st3r]

Originally Posted by ptuning

Apologies to the FL folks.

Thanks. FWIW, if I ever moved to FL, it'd be Miami. I somehow recall it being less humid there than the Central Atlantic coastline of FL and the beaches are awesome! No state income tax and laid back car and motorcycle laws are a definite bonus too!

They have to have some perks there for a state that gets hit with as many Hurricanes as they do.

[ptuning]

Originally Posted by carbonBLUE

this is correct, what headers have yall tested with your kit?

resonance and restriction play big roles in the "dip" we all see. Part of which on the stock headers, is purposely implemented to create more back pressure during that rpm range for better mileage and allows us to rev into that range without taking a huge hit on mpgs during spirited driving.

We've dyno tested our 4-1 header NA vs stock, both with no tune, and compared it with a popular 4-1 header from a dyno day that had an AFR tune. The other header added some torque to the dip, but lost way more torque from the first torque hump than it added to the dip. The gains that we saw on the top end with the other header could have easily been achieved by leaning out the AFR's and adding timing on a stock engine.

I would say that if someone can develop a header that can, by itself with no tune (especially an E85 tune), straight line the torque curve from one hump to another, this may be nothing short of a miracle and is something that we'd definitely want to test with our turbo system.

The ones that come even close are comparing a bone stock car to one with intake, header, exhaust, and a full E85 tune, which is not a very good way to determine the gains for just a header.

We'll revisit the development of our 4-1 header later on down the road. It will likely be a header/overpipe combo.

[carbonBLUE]

Originally Posted by ptuning

We've dyno tested our 4-1 header NA vs stock, both with no tune, and compared it with a popular 4-1 header from a dyno day that had an AFR tune. The other header added some torque to the dip, but lost way more torque from the first torque hump than it added to the dip. The gains that we saw on the top end with the other header could have easily been achieved by leaning out the AFR's and adding timing on a stock engine.

I would say that if someone can develop a header that can, by itself with no tune (especially an E85 tune), straight line the torque curve from one hump to another, this may be nothing short of a miracle and is something that we'd definitely want to test with our turbo system.

The ones that come even close are comparing a bone stock car to one with intake, header, exhaust, and a full E85 tune, which is not a very good way to determine the gains for just a header.

We'll revisit the development of our 4-1 header later on down the road. It will likely be a header/overpipe combo.

PM'd

[SnapOv3st3r]

PTuning you are my hero!