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To my understanding the 6870 is the biggest of the mid frame precision, I know of a few 2.8s with 6870s. 

From what people have said the 6870 on a 2.8 will have similar response to a 6466 on a 2.6 but make closer to 850-900hp at the wheels 

I have spoken to one person with one and he says he’s all in at around 4100 with a 1.15 rear on it 

The logic is that with my new head and inlet setup i should retain the same response and make more overall power on the 6870

It is also suggested I may hit the back pressure wall on the 6466

 

All in all I am in a holding pattern until seeing what the 6466 does on the new setup and just seeking results on a 2.8 6870

  • Like 1
10 hours ago, BK said:

 If so on track isn't Simon R. still quicker with a 6262 on a 2.6 ?

first of all, how much did Simon pay you to say that 😁

 

The debate on that is largely irrelevant as both of us run around 550/600whp on the track, as opposed to 800+ when doing other events.

 

 

  • Haha 1
8 hours ago, r32-25t said:

To my understanding the 6870 is the biggest of the mid frame precision, I know of a few 2.8s with 6870s. 

From what people have said the 6870 on a 2.8 will have similar response to a 6466 on a 2.6 but make closer to 850-900hp at the wheels 

I have spoken to one person with one and he says he’s all in at around 4100 with a 1.15 rear on it 

And you dont even need the 1.15..

Even in a 3.0 they are all in compressor wise on a 1.00

 

8 hours ago, r32-25t said:

To my understanding the 6870 is the biggest of the mid frame precision, I know of a few 2.8s with 6870s. 

From what people have said the 6870 on a 2.8 will have similar response to a 6466 on a 2.6 but make closer to 850-900hp at the wheels 

I have spoken to one person with one and he says he’s all in at around 4100 with a 1.15 rear on it 

Far out man, a responsive wheel 900hp !

I can't even comprehend that as being realistic. Someone really needs some 6870 results here

  • Like 1
  • Haha 1
13 minutes ago, BK said:

 

Far out man, a responsive wheel 900hp !

I can't even comprehend that as being realistic. Someone really needs some 6870 results here

It is possibly realistic depending on what boost number he is talking about and what size engine, how long it's loaded to achieve that or maybe how much nitrous.

For what it's worth this dyno plot is of a RB32 with VCam running a 6870, it's going to be harder to make a 6870 come on quicker than this on a sensible ramp run on a dyno without nitrous.  Definitely not with an RB28

 

FB_IMG_1619826676475.jpg

Edited by Lithium
16 minutes ago, BK said:

 

Far out man, a responsive wheel 900hp !

I can't even comprehend that as being realistic. Someone really needs some 6870 results here

Me either it’s why I’m asking for other people who have done it.

22 minutes ago, jet_r31 said:

And you dont even need the 1.15..

Even in a 3.0 they are all in compressor wise on a 1.00

I would be looking at the 1.00 rear if I did it. At the moment  I’m looking to put a 1.00 rear on the 6466 and thought I’d ask about the 6870 because of the number of people suggesting to go that way 

18 minutes ago, r32-25t said:

I would be looking at the 1.00 rear if I did it. At the moment  I’m looking to put a 1.00 rear on the 6466 and thought I’d ask about the 6870 because of the number of people suggesting to go that way 

You tune with JEM right ? What did they say ?

14 hours ago, BK said:

Thanks for that mate. So there is some merit to the guys suggesting to maybe skip the 6466 stage in favour of the 6870 in the first place ? This was my original intention.

I know the 6870 will make more power, but surely that will translate into a slower car everywhere else but the strip ?

Dont know

They all have there place.. The 6466 is still the best allrounder.. Its a epic little turbo. Slower everywhere else could depend on style of circuit you use?.. Comp, camshaft/transmission type  even tyres used for corner exit.

So could be merit in it.. But apart from efr the 6466 is hard to top

I haven’t got Facebook to be able to get it, I found it using the mrs computer and it was the usual photo of a screen that’s impossible to read so I went off his comment further down the page 

2 hours ago, r32-25t said:

I’m building a street car that I can take roll racing, not a car dedicated to winning roll racing. there’s a difference! 

The only difference is turbo? 

You're going to be off boost until 5,000rpm anyway....so what difference does turbo size make at this stage?

Save yourself the money - buy the biggest turbo possible - because I guarentee you won't be happy with the 6870 in a few months time....

 

 

2 hours ago, r32-25t said:

I’m building a street car that I can take roll racing, not a car dedicated to winning roll racing. there’s a difference! 

Realistically a 2.8L with a 1000+hp turbo isn't gunna be THAT streetable. It kinda puts you in "the middle" as it's not going to be good on the street & it's not gunna get you anywhere in roll racing either.

Obviously this is just my opinion and no doubt a 650kw car is gunna pull like a freight train once it wakes up!

 But making a car that's gunna be laggy on the street to compete in the 2nd biggest dick shwinging contest after WTAC every couple of weeks/once a month is going to ruin the car for all those other drives you will take it on.

I think you're off ya head ditching V cam and the 6466 man. 

6466 + vcam + 2.8L + sequential will make for a brutally fast/responsive car thats gunna do street duties, SAU cruises amazingly well! But realistically it ain't gunna change your roll racing result at the end of the night cos you're going home once the big boys come out to play anyways. 

 All you're doing is sacrificing a f**ktonne of low/midrange & overall average grunt for a lazy 50kw up top dude? At the expense of 80-100kw of midrange grunt  and far more drivability off boost ditching V cam.

Ditching V cam on a street car is a huge mistake. You've felt the gains its given you and you're basically going 2.8L to give you the low down grunt V cam has given you. You're taking a big sideways step with shit cams and no skinny cam. Bigger cubes & v cam is the only logical choice for a street car. All you're building is a top end screamer in the "guise" of a street car imo.

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