RB28 6466 A/R Change

[hattori hanzo]

Has anyone done a back to back dyno comparison on changing the rear housing over, i have had a good trawl of the forums and can't find anything within the last 10 years. 

Currently have a .84 on RB28 doing 800whpish at 30psi however it has hit a bit of a wall, looking at going to 1.0 or 1.15 to make slightly more top end.  

Current graph below don't mind loosing a small amount of that midrange ?

[BK]

Also need to know as I'm going to purchase this soon (in the next week or so) in either 1.00 or 1.15 a/r for my Nitto 2.8

[GTScotT]

Firstly, do your cams and head allow for more?

By my eye I think the nose over is more mechanical than it is in the turbine housing.

[hattori hanzo]

On 4/9/2019 at 6:17 AM, GTScotT said:

Firstly, do your cams and head allow for more?

By my eye I think the nose over is more mechanical than it is in the turbine housing.

Winding more boost in just resulted in it dropping off in the top end, leading to believe back pressure is the issue from the rear housing. 

Cams are HKS 272's minor touch up work in the head to accommodate the new cams. 

 

Really keen to follow the rear housing comparison as the turbo needs to be rebuilt in anycase, so is cheap top end power but I want to see at what cost of the bottom end in rpm terms. 

[BK]

Hanzo, couldn't wait, I ordered the Gen2 6466 T4 twin scroll in 1.00 a/r yesterday.

[Lithium]

A chap I know has tried all of them, actually just tuned a car running a 6466 with a 1.00 and is looking at going 1.15 - said the difference in flow between .84 and 1.00 is significant in itself, picked up a LOT of power "pound for pound" when going north of 20psi and only lost about 200rpm on a stock stroke RB26.  It's holding peak power at around 8000rpm with the RB26 at ~650awkw on a Dynapack on E85.   He is pretty certain the 1.00 is a better balance of response versus power than the .84 even on an RB26.

 

 

[GTRNUR]

My setup has the same issue with the 1.00 6466 choking the 3.4lt.  705whp at 5500 rpm till redline.  It seemed the hot side was just completely maxed out, at 30psi.

I've got 1.3 housing here to go on the car which should really liven it up in top end and make it a little less savage in mid range.

[hattori hanzo]

On 4/11/2019 at 4:21 AM, Lithium said:

A chap I know has tried all of them, actually just tuned a car running a 6466 with a 1.00 and is looking at going 1.15 - said the difference in flow between .84 and 1.00 is significant in itself, picked up a LOT of power "pound for pound" when going north of 20psi and only lost about 200rpm on a stock stroke RB26.  It's holding peak power at around 8000rpm with the RB26 at ~650awkw on a Dynapack on E85.   He is pretty certain the 1.00 is a better balance of response versus power than the .84 even on an RB26.

 

 

would love to see some graphs if available 

[33GTRV]

I have a 2.8 with a .84, it's a f**king weapon on the street mate, are you racing the car? I have a conservative 500awkw and I regularly get turfed from the track even on a roll through. 

[hattori hanzo]

1 hour ago, 33GTRV said:

I have a 2.8 with a .84, it's a f**king weapon on the street mate, are you racing the car? I have a conservative 500awkw and I regularly get turfed from the track even on a roll through. 

car has gone 9.6 @ 146mph 

In terms of goals it is pretty much done, however it looks like we are leaving some power on the table. 

 

car gets used for everything from circuit / drags / runway racing and streeted so is an allrounder. I don't mind loosing a small amount of bottom end for top end gain, however just trying to quantify the impact. Sending the turbo off for rebuild shortly, will more than likely just do it.  

 

 

[33GTRV]

If you are under it and at 9.6/146 You are already leaving a bit behind. Great times for a streets never the less. 

[hattori hanzo]

1 hour ago, 33GTRV said:

If you are under it and at 9.6/146 You are already leaving a bit behind. Great times for a streets never the less. 

what do you mean? What are you trapping on the 1/4? 

[33GTRV]

149 mate. 140 to 144 with street suspension, 149 and as high as 151 with bone stock suspension and a good wheel alignment. The track here is very very very good to the 1/8th, one of the fastest in the southern hemisphere, which suits the datsun well. What suspension are you using? 

[hattori hanzo]

On 4/22/2019 at 10:48 AM, 33GTRV said:

149 mate. 140 to 144 with street suspension, 149 and as high as 151 with bone stock suspension and a good wheel alignment. The track here is very very very good to the 1/8th, one of the fastest in the southern hemisphere, which suits the datsun well. What suspension are you using? 

interesting what times did you trap also? do you have the slip? keen for more details on your car to compare notes, do you have a build thread? 

[TurboTapin]

Bringing this bad boy thread back from the dead. I'm just about to purchase a 6466 and I'm also stuck between ordering a .84 or a 1.0. 

I was leaning towards a 1.0ar but being that I'll be running on pump gas + meth as opposed to E85, I'm worried about spool. This is on a 2.8 with VCT, 272 cams and a fair bit of porting. Goal is 600wkw on a mainline dyno.

[r32-25t]

The .84 rear on my stock bottom end 2.6 with vcam and e85 was all in at 4,100 and was an absolute weapon on the street, I only used the high boost twice and once it tried to kill me (turned out to be a transfer issue) 

[Piggaz]

On 23/9/2022 at 9:17 AM, TurboTapin said:

Bringing this bad boy thread back from the dead. I'm just about to purchase a 6466 and I'm also stuck between ordering a .84 or a 1.0. 

I was leaning towards a 1.0ar but being that I'll be running on pump gas + meth as opposed to E85, I'm worried about spool. This is on a 2.8 with VCT, 272 cams and a fair bit of porting. Goal is 600wkw on a mainline dyno.

1.00 or 1.15.

 

[BK]

No smaller than 1.00 on 6466. Dont worry the 1.00 a/r is not too big, I'm  running on both the 32s. Stock cams and 2.6 or the 2.8 and big cams are both great to drive as it's just such a flexible turbo.

[hattori hanzo]

I lost nothing going to a 1.15 and did just over 600kw on E85 so you should be fine

 

I am actually moving to a smaller 6062 turbo shortly if you want to buy my 6466 with a .84 and 1.15 housing, it was rebuilt by precision in america in feb this year, been used about twice since.

I am going smaller as i am doing more rallysprint style stuff these days, and can get alot more down low and 500kw from a 6062 which is what we need for rallysprint.

 

[TurboTapin]

22 hours ago, hattori hanzo said:

I lost nothing going to a 1.15 and did just over 600kw on E85 so you should be fine

 

I am actually moving to a smaller 6062 turbo shortly if you want to buy my 6466 with a .84 and 1.15 housing, it was rebuilt by precision in america in feb this year, been used about twice since.

I am going smaller as i am doing more rallysprint style stuff these days, and can get alot more down low and 500kw from a 6062 which is what we need for rallysprint.

 

Thanks for the info. I would buy it from you but I'm presuming you're not anywhere close to Canada and shipping would put your price into new turbo territory. 6466's are had here for 2650$CDN new to the door. Let me know, thanks.