Gt2871R external option?

[BaldTurboFreak]

GT2871 will have about the same advantage on the BW+ as the BW+ has on the stocker.
About 50-60hp.

[nikos7575]

How Much Whp Do You Expect With That Kit (2871)?? With DECat , 3" Exchaust And Ic ON THE CAR ?? Cost Wise Without The Program What Will Be The Cost ?

[BaldTurboFreak]

How much boost? More boost=more whp up to the max flow of the turbo.

The 2871 should lay down 375-400whp at high boost levels. Since it wakes up earlier than the GT30R it should put down fantastic torque in the midrange. Likely more than 400wtrq on higher boost.

TUning is not included so it will not effect pricing.

I dont beleive there will be any cost difference, the only difference is componenets are the turbo and Turbine housing. If the turbo is any cheaper than a gt30R then it will be reflected.
So assume that it's the same pricing as the GT30R setup.

[oldskool]

Based on your experience, do you think the peak HP with this turbo would occur at an RPM within the limits of the stock valvetrain, say at or before 6500 RPM? I love the idea of the GT3076 and around 400whp, but not so much having to rev to 8k rpm to take full advantage of it.

I guess my question is which turbo fills the most area under the curve up to 6500RPM?

[BaldTurboFreak]

Full manifold pressure is achieved at 3400 rpm with the GT30R.
I would have to wager that the gT2871 would have the same boost by 2700 or less.

The Gt3076R makes peak power above the max injection window, so you may see a more street friendly setup. 2500-6500 rpm.
It will still make 400 whp, just take a coupla more PSI.

[Iceman]

So BTF any news from the GT2871r... possible to put it to our cars....

[Frank I]

Originally Posted by BaldTurboFreak Full manifold pressure is achieved at 3400 rpm with the GT30R. I would have to wager that the gT2871 would have the same boost by 2700 or less. The Gt3076R makes peak power above the max injection window, so you may see a more street friendly setup. 2500-6500 rpm. It will still make 400 whp, just take a coupla more PSI.

Rick:

What type of TIP to IMP ratios are you getting with the different # Turbos and with the compressor modded B/W?

Thanks
Frank

[BaldTurboFreak]

Originally Posted by Iceman So BTF any news from the GT2871r... possible to put it to our cars....

Most definitly .

[BaldTurboFreak]

Originally Posted by Frank I Rick: What type of TIP to IMP ratios are you getting with the different # Turbos and with the compressor modded B/W? Thanks Frank

Have no data on the BW, the Gt30R though has a very favorable Tip mip ratio. Pending on cam timing. Typically speaking it's no more that 1.2/1.
Although I havent seen any prolonged periods of crossover, a better exhaust and intake situation may provide a longer RPM window of said condition.

[Frank I]

Originally Posted by BaldTurboFreak Have no data on the BW, the Gt30R though has a very favorable Tip mip ratio. Pending on cam timing. Typically speaking it's no more that 1.2/1. Although I havent seen any prolonged periods of crossover, a better exhaust and intake situation may provide a longer RPM window of said condition.

Rick:

Just to insure we are talking about the same thing. The ratio I am speaking of is Turbine Inlet Pressure (TIP) and Intake Manifold Pressure (IMP). I have never heard the term "mip" but if that is Manifold Intake Pressure, we are just using different terms for the same thing. Please forgive me if IMP is now termed MIP since I have been out of the Turbo R&D Industry since 87.

When we were performing R&D at Garrett back in the mid 80's the rule of thumb for good street turbo systems would be a ratio of TIP to IMP to be around 2. If the ratio was greater than 2 the turbo would be considered too small or choking the turbo system down. If the ratio was less then 2 the boost threshold would be higher and not considered good for street conditions.

However as the ratio came down, power would of course go up and hence, on race turbo systems we tried to get the TIP/IMP ratio to be less than 1. In fact on Formula 1 cars of the mid 80's we started to become successful at getting over 1000BHP out of 90 CI engines. We could achieve this when we started Variable Area Turbine Nozzle (VATN) R&D. This allowed for us to create low boost thresholds while having boost exceed TIP when boost would stabilize at the max parameter.

That was the reason for my initial question of TIP/IMP ratios of the various Garrett turbo's you were referencing. I have no idea what today’s ratios are on the different Garrett models and thought perhaps you would know.

If your quoted ratio of 1.2/1 is the TIP/IMP ratio that is a hairy number for a street turbo system but it should make a ton of power.

Rick thanks for the initial response and on a side note I enjoy your dialogue on the forum. It is nice to read your threads and posts. I always enjoyed young engineers with an abundance of talent, enthusiasm and the guts to experiment and attempt to exceed current day technology. I was considered one of those bold mavericks in my early years and fortunately it allowed for rapid advancement up the organizational ladder. For those of us who may have been a bit like you we may have made a few mistakes along the way but we also were the trend setters. In my eyes, you appear to be a trend setter and I hope you keep up the good work and great enthusiasm.

Frank I

[wegman]