Turbo builds

[Mspir3d]

What AR you running?

The BW is a 64.5/67 with a .81 a/r

I havent had experience with Garrett in over 15 years but I believe their reliability is similar to BW.

[Nicholas1996]

Do you remember what at the precision was.? Mines a 1.0

[Mspir3d]

Do you remember what at the precision was.? Mines a 1.0

The precision was the same A/R

[Nicholas1996]

The precision was the same A/R

Interesting. Mines a 1.0

[Mspir3d]

Interested in feedback from anyone running a 6870 or 6766. Especially in terms of spool time compared to a 6266. Was thinking about stepping up the turbo eventually from a 6266 JB to maybe a 6766 BB and wanted to know how much it would change when boost came in. Originally went with the 6266jb for a few reasons. First being that the motor was stock and I didn't think anything more was necessary. Second, the clutch was stock so I figured a journal bearing would spool a bit later and be easier on the clutch. Third, it was pretty cheap for a new one. However, now the motor is currently being built and I got a twin disk clutch.

Here is my setup by the way:

Maximum PSI kit (intake manifold, intercooler, spa exhaust, etc)
Precision 6266JB
Tial WG
AEM Infinity
AEM boost controller
Flexfuel
Dual In-tank walbro 450's
8AN feed, 6AN return
Radium Rail
ID1050's
30 shot of nitrous (never actually used and probably wont. Had it and just threw it in to be ridiculous)
Motor (in the works, machined, new bearings, etc. Here are the highlights)
-CP 9.5:1 pistons (87.25mm)
-Carillo rods
-ARP L19 headstuds
-Supertech valve springs
DKM twin disk clutch

I didn't know things like pistons took 5 weeks, plus things are just out of stock from covid, so the motor is currently waiting at the machine shop. Once they have everything it should be quick, so I am hoping to have the car running by the end of August. I am happy with the 6266 and will run that for a bit, but with all this cash into the motor, I feel like it would be a waste not at least have a tune that steps it up a bit lol. It is worth noting that I have a map for E85 but mostly run pump 93. I can step up the boost on the new motor but on pump gas I wouldn't go crazy. So I am also wondering if the amount of boost it would take a 6766 to match the power of a 6266 at say 20psi would be significantly less or just negligible.


Eventually I am going to change the turbo to a ball bearing, but my question is if there is much of a benefit to a 6766BB or 6870 over the 6266BB or 6466BB which most people use.

On a side note, on stock motor on pump 93, I was running 12psi at most. The car had a base map that ran fine but was really just meant to be safe for the time being. Might have gone to maybe 14psi if everything looked good but never did. With this motor being lower compression, how much can I raise the boost and still be safe on pump gas?

That's a really interesting setup. What's the story behind it?

[mleveroni]

That's a really interesting setup. What's the story behind it?

I picked up the infinity, maximum psi kit, and some of the fuel stuff off someone returning to stock. Just missing a turbo and some fuel lines. After it was running, added the flex fuel sensor, boost controller, and injectors. Ran like that for a little then I found an alarming amount of metal in the oil. Just assumed a bearing went bad so I took the motor out and tore it apart. To my surprise, everything looks fine, never found the source of the metal. Figured my options were to try my luck with another stock motor, or rebuild mine. So I went with the rebuild which is where I am currently at.

[Mspir3d]

So I went with the rebuild which is where I am currently at.

Very nice, I just finished building my engine as well. I took it out for it's first 5 miles late last night. The last 7 months was a ton of work so I'm excited to get it broken in.

[Nicholas1996]

Very nice, I just finished building my engine as well. I took it out for it's first 5 miles late last night. The last 7 months was a ton of work so I'm excited to get it broken in.

Excited to see what yours puts down. Was going to to go do some road tuning on mine tonight but the weather looks bad.

Edit: went out and did some tuning. Set up boost by gear. Ran out of fuel at 24ish psi on my 1100cc injectors. Car is fun for sure

[Mspir3d]

Excited to see what yours puts down. Was going to to go do some road tuning on mine tonight but the weather looks bad.

Edit: went out and did some tuning. Set up boost by gear. Ran out of fuel at 24ish psi on my 1100cc injectors. Car is fun for sure

That's really good. Have you got on a dyno with it yet? You must be running some sticky tires. My firehawks grip well at 9-10 psi, but into the 20 psi range it will spin them above 90mph.

[Nicholas1996]

That's really good. Have you got on a dyno with it yet? You must be running some sticky tires. My firehawks grip well at 9-10 psi, but into the 20 psi range it will spin them above 90mph.

Just some Kumho ecsta ps91. Nothing crazy. Once they’re warm they do Ok

[Mspir3d]

Excited to see what yours puts down. Was going to to go do some road tuning on mine tonight but the weather looks bad.

Edit: went out and did some tuning. Set up boost by gear. Ran out of fuel at 24ish psi on my 1100cc injectors. Car is fun for sure

Are you running a boost a pump?

[Nicholas1996]

Are you running a boost a pump?

No sir. But the duty cycle is %95 . I may dump another 525 lph in the tank ( I have a Dual hanger) and see what it does. At this point I’m not sure if there is going back. I’m thinking of getting as much fuel as I can into it and seeing what the 6266 does when really cranked to the max. It’s got a 1.0 AR housing so it should flow well enough.

[Mspir3d]

No sir. But the duty cycle is %95 . I may dump another 525 lph in the tank ( I have a Dual hanger) and see what it does. At this point I’m not sure if there is going back. I’m thinking of getting as much fuel as I can into it and seeing what the 6266 does when really cranked to the max. It’s got a 1.0 AR housing so it should flow well enough.

I think maxpsi maxed their 6266 out at 26 psi on their run into the 9s. It was making 750 whp IIRC. I also found this regarding a/r: https://www.e46fanatics.com/threads/...ng-ar.1063132/ just sharing because I thought it was an interesting read.

[Nicholas1996]

I think maxpsi maxed their 6266 out at 26 psi on their run into the 9s. It was making 750 whp IIRC. I also found this regarding a/r: https://www.e46fanatics.com/threads/...ng-ar.1063132/ just sharing because I thought it was an interesting read.

That’s a good read. Yeah I don’t see the 6266 being able to handle too much more. I contacted max psi. They want to offer me a 6466, but they want to install and tune it. Don’t know why they can’t just sell me a turbo but anyways, Can’t happen as I live far away. Besides that I’d like to go with a Borg Warner of some sorts. But I hear it’s laggy. Decisions decisions

[Mspir3d]

Hopefully I can get the car broken in and on a dyno with a rpm readout soon. It was down most of this week waiting for a new starter. I'm curious to see where it actually spools up. I wonder if a local fabrication shop could cut and weld an exhaust housing for you if you bring in your current one.