As some of you may know, I have had a customer that decided to do a bit of a custom mid mount kit, using a Precision 7675 T4 .96 a/r billet JB turbo. The run was made on the new DJ dyno.

Well, the numbers are in:




Video:

 

Awesome numbers and great curve.

Any additional information available? Cams/headwork/compression ratio?

 

How much psi? what fuel? what was done to the motor?

Nice numbers!

 

Low CR (8.5 I believe), not sure about the rest of the engine.

E85 and I believe around 25psi. The motor was obviously built...you would have to contact Dynosty for a build like this, as I only provide the turbo kit.

 

Lots of power for 25psi. the 7667 has a lot more to go. Seems a little bit on the laggy side tho. Maybe a 6766 could make to close to the same power ( more boost obviously) and spool sooner?

 

^ wow.. yeah that it WAY up there in the powerband for sure.. impresive though no doubt.. but id most likely resize the snail too if it were I. Id imagine this is a dyno queen build tho.. i couldnt imagine trying to actually drive a 900 hp Z.

 

I am excited about the recent release of the new 6870 turbo. It is rated at 1,050 HP (105lbs/min worth of flow) from Precision, and I really think it will do well on similar builds on the VQ.

The nice thing about that turbo is the large 70mm turbine in a nicely sized T4 housing. That, IMO will be the go to turbo for those that are looking at building 800whp + cars.

 

per Dustin, it was 30psi and out of fuel pump (255 and a 485).

powerband as expected for a 76mm and a 75mm turbine. not terribly lazy, but the 6870 would def be a better option in the future for someone that doesnt want to get very custom with the fuel pump setup. 6766 is still probably the best street turbo, maxing out around 950whp.

 

Insane... Great curve

 

Thanks for the accurate info on the boost level. I talked to Hal at SEMA, and for some reason I thought he mentioned 25psi...

Hope that PTE releases the twin scroll T4 soon on the 6870...pair that up with the twin scroll kit and good things will happen, especially with the VHR engines.

 

Great work BP and Dynosty!

 

Impressive.

 

BP, what does it take to fit this 76mm kit?

Could you go into so detail here?

Thank You,

TimRod

 

Yeah not a problem....

For starters, the 76mm turbo only comes with the “H” compressor cover. It has a 4” inlet and 3” outlet. In order to make it sit above the subframe, it is necessary to “massage” the under- side of the car just a bit..it is very minor since you would only be making enough room for a small fraction of a circular compressor cover.



Other than that, it fits perfectly:





3.5” intake:



Because I ended up using a different/larger FMIC:




The IC plumbing was changed a bit…instead of entering the vertical FMIC on the drivers side, it goes all the way across the engine bay to the passenger side:



Standard FMIC:




Since the standard FMIC is capable of flowing around 2,000cfm I believe that it would have been plenty for this application, however, I did end up going with the larger core anyway.


The guys at Dynosty had no issues with the kit on pump gas, but when it came to high PSI and E85 the intake became a restriction. They ended up using a larger K&N air filter, and I believe a larger 4" intake.

As a result of this, if I end up building another custom kit with this size turbo, I would modify the rear transmission member in order to accommodate a straigh 3.5" intake. In other words, I would get rid of the bend/coupler at the compressor inlet. This would allow for much better flow to the turbo at those boost levels.

Here is the clearance when a string is pulled between the front sub-frame and the rear skid plate:




With a bit more "massaging" it would be very easy to create another 1/2" to 1" clearance.

 

Charles, I wounder if you could chime in and talk about the Fuel Restrictions with E85 on this car @ 935whp.

What do you think this Fuel System is capable of with the same setup on C16? (Whp Wise)

What would the Fuel System look like to max out the turbo?

Thanks,

TimRod

 

How SOL am I with Long tube headers for a BP kit? ahaha

 

How does this work with the G35's since they dont have the intake like 350's?

 

You just drill a hole in the rad support. This is very common with many kits for the G cars.

 

I dont know what they are running for the entire fuel system... Dynosty builds their own fuel systems for their projects, but they do seem to use my twin pumps pretty often. I could of swore that they made high 900s on their old dyno (a lower reading machine than a dynojet) with one of my 255/485 twin pumps, and that was with E98 too I believe. But maybe they were using a voltage booster on that car. Not sure!

Either way, if that twin pump is making 930rwhp dynojet with E85 at standard system voltage... then you can safely assume that volume of fuel will make 1100-1200rwhp with gasoline. You can get more with a voltage booster if you want. I also have a triple pump for the 350z that uses 255/485/485. Dynosty had one, but I am not sure if they used it in the end or not. I let them do initial testing with it and I wasnt even sure if the level sensor was going to fit in or not. The triple was a rush-job and wasnt fully refined. I guess I should find out what they ended up doing with it and if it fit OK etc. I made 2 of them... so there is one more here still.

Other things for considering is if Dynosty may or may not have performed any modifications to the twin pump to make this power. I just dont know, they have tested it further than I have in this case!

The twin pump will possibly see a redesign in 2015. It was a long time ago I designed it, and I have learned a lot since. I have to make a new model for the 370z to support my new twin GTX3582 setup... and it will probably trickle down to the 350z.

 

ya they were out of fuel pump with the 255/485. sounds about right as a single 485 supports around 750ish E85.

divided housing on the 6870 are being ordered now with delivery in december.