Changed turbo and results kind of suck?

20psiofevil

Active Member
*Warning this is a ford v6 in question but you guys have the greatest turbo v6 tech on the webz and plethora of turbo v6 information and this is why I post tech questions here. Also because you'll have that guy Bison among many other greats!:)

Mainly it's just the 60' but for some reason I cant get the car to 60' like it did last year. The best with the new turbo has been 1.41 and previous was a 1.29 with several 1.3's last year. The 1.29 was with a borg s366 88ar open t4 3100rpm launch 10psi and the turbo on the car now is a cast 70mm p-trim 96ar and 3400rpm launch 12.5psi. I'm not seeing any tire spin as I only go when there is good track prep.

I just cant wrap my head around the physics of whats going on here. The shaft of the 70mm is much lighter than the borg unit including the smaller turbine. Is it possible momentum and leverage of the heavier shaft/wheel are what made the s366 hit harder, or could it be the 96 ar t4 is just to big? Should I try to launch the car higher with the 70mm? Shift rpm is 6500rpm.
 
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I would launch at a higher psi and see if it help . I think you are just not in the sweet spot when you launch . So bump it up and see if it helps
 
You haven't supplied enough info to determine what is happening. 60' is an indicator of traction and power. If mph is the same maybe you need to asses the a/r. Bigger a/r doesn't usually increase power much and can require a few hundred more rpm to hit full boost which can have drastic effects on 60'. A p trim can easily support 9 sec power and 1.3x 60' times in a 3500lb car. The shaft diameter has little to do with it. The turbine head and exhaust pressure will be the biggest determining factors in rpm required and mass flow out. It may take 300hp of exhaust to generate enough exhaust pressure to move 600hp worth of air from a given compressor at a given output pressure. Post launch rpm to full boost times and driveshaft speed data


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*Warning this is a ford v6 in question but you guys have the greatest turbo v6 tech on the webz and plethora of turbo v6 information and this is why I post tech questions here. Also because you'll have that guy Bison among many other greats!:)

Mainly it's just the 60' but for some reason I cant get the car to 60' like it did last year. The best with the new turbo has been 1.41 and previous was a 1.29 with several 1.3's last year. The 1.29 was with a borg s366 88ar open t4 3100rpm launch 10psi and the turbo on the car now is a cast 70mm p-trim 96ar and 3400rpm launch 12.5psi. I'm not seeing any tire spin as I only go when there is good track prep.

I just cant wrap my head around the physics of whats going on here. The shaft of the 70mm is much lighter than the borg unit including the smaller turbine. Is it possible momentum and leverage of the heavier shaft/wheel are what made the s366 hit harder, or could it be the 96 ar t4 is just to big? Should I try to launch the car higher with the 70mm? Shift rpm is 6500rpm.
How soon does it hit full boost from 12.5 psi launch boost?if seen the cars slow down when the boost curve is slower.
 
Sorry for responding so late but been a busy week with my wife having surgery Monday.

I have been unable to log analog inputs like fuel and map so I base my boost curve off my fuel pressure since it runs through the obd2. After looking it over it doesn't even look like it's hitting full boost in 1st. I'm trying to target a solid 20-22psi manifold pressure and only hitting 17-18psi going off 43psi base fuel pressure. Also after thinking about it more I honestly think this scg-1 boost controller is the issue. I may end up just stacking springs in the wg if I cant this controller dialed in. I have 2 more track outings this year and I'm going to be logging the boost controller af, map, and rpm.
 
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Sorry for responding so late but been a busy week with my wife having surgery Monday.

I have been unable to log analog inputs like fuel and map so I base my boost curve off my fuel pressure since it runs through the obd2. After looking it over it doesn't even look like it's hitting full boost in 1st. I'm trying to target a solid 20-22psi manifold pressure and only hitting 17-18psi going off 43psi base fuel pressure. Also after thinking about it more I honestly think this scg-1 boost controller is the issue. I may end up just stacking springs in the wg if I cant this controller dialed in. I have 2 more track outings this year and I'm going to be logging the boost controller af, map, and rpm.

FWIW When I was looking into the SCG-1 from Innovate it seemed that there were quite a few people that ran into boost control issues like you are having.

It seems the SCG-1 is either a good wideband, or good boost controller, but it doesn't seem to have both aspects of the controller working at the same time very often-at least from what I have gathered... I read similar instances enough to where I took that boost controller off my list and no longer recommend it to anyone.
 
FWIW When I was looking into the SCG-1 from Innovate it seemed that there were quite a few people that ran into boost control issues like you are having.

It seems the SCG-1 is either a good wideband, or good boost controller, but it doesn't seem to have both aspects of the controller working at the same time very often-at least from what I have gathered... I read similar instances enough to where I took that boost controller off my list and no longer recommend it to anyone.

Innovative makes a good product, nothing against them but the scg-1 is not a good match for my car. I've completely gone backwards this year with this car. Should of never traded my borg s366 for the s467 and this 70mm with the 96 ar doesn't hold a candle to the s366 box turbo. Low end or up top! I don't understand how a s366 88ar open t4 can make 10-11psi on 3100 rpm and the 70p with 96 ar only makes 6-7 with 3400.
 
Linear boost curve and not hitting full boost until 3rd gear. Base fuel pressure is 43.5psi with 1:1 rise (how I determine boost). Bottom purple line is fuel pressure, yellow is rpm, other purple is tp. Had to feather it when the car went sideways off the line. 6.65 @ 106.5 mph 1.57 60'. No exhaust leaks. I'm wondering if the 96 at bolted to a ptrim is the cause. Opinions?
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Also leaned the engine out a bit and revised my timing table running vp 110.
 
Innovative makes a good product, nothing against them but the scg-1 is not a good match for my car. I've completely gone backwards this year with this car. Should of never traded my borg s366 for the s467 and this 70mm with the 96 ar doesn't hold a candle to the s366 box turbo. Low end or up top! I don't understand how a s366 88ar open t4 can make 10-11psi on 3100 rpm and the 70p with 96 ar only makes 6-7 with 3400.

The SXE400 series is larger than your SXE300, so keep that in mind when comparing them.

The S400 also uses a 74mm turbine wheel, whereas the S300's use a 73mm or 69mm turbine wheel.

I'd send your turbo into Reed at WORK Turbos and have him swap the wheels to something smaller. Or just sell yours and buy a more properly matched turbo.

Look into the Boost Leash boost controller for what you are doing. Or the E Boost 2 from Turbosmart. Those will give you a lot more ability to fine tune your boost curve and really play with the ramp rates and spoolup. The Boost Leash allows you to use CO2, whereas the Eboost 2 does not, but the EB2 has an incredible array of programmable tuning parameters.

If you decide to go with the EB2, I can help ya save a few bucks if you're interested. I'm a dealer for WORK Turbos, and they carry Turbosmart.
 
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