6 blade vs 11 blade compressor

[mike diesel]

Some of you have probably seen my boost density thread about billet wheels.

Now the question is, which design would be better. 6 blade or 11 blade?

My research shows the 11 blade wheels come on quicker but choke up on the top end, 6 blade wheels come on a little slower but keep flowing very well on top, also they make some serious whistle.

I was set on having an 11 blade wheel made but now im second guessing and think I want 6 blade. What would you guys recommend? Garrett seems pretty fond of 11 blade wheels...borg seems partial to 7 blade wheels.

Basically all im trying to do is gain any efficiency and spool up I can get by going to a billet wheel in my s472.

 

[duramaxzak]

Fleece run's a 6 blade on there Billet S471 and seem's to good power.

 

[mike diesel]

After doing some research I think im leaning towards a 6 blade.

 

[1stgensleeper]

From what I have gathered, the 11 blade wheel will actually flow more than a 6 or 7 blade in a single application. The 6 and 7 blade wheels are better in possitive inlet pressure situations. (I.E. Compounds)

 

[mike diesel]

Now the age old question...will the 11 blade wheel keep the turbo quiet? Seems stock 11 blade dmax wheels have almost no whistle. Hate to say it but the whistle is also a deciding factor.

 

[Yellow Jacket]

11 blades are the most quiet, I put a 6 blade billet in the s475 I put on my brother's 93 KW W900, we love the sound and performance.

I had a GTX4508 we ran on our 3.0 truck 4 years ago, POS made 2 passes and compressor hit the cover, sent it to Precision and they put their 7 blade wheel and cover on and it blew the factory 11 blade gtx wheel out of the water on performance...

 

[mike diesel]

Ok well I think ive made up my mind. 6 blade it is.

 

[DMAXchris]

Not a fan of 11 blade. Like you said, it really chokes them up on the top end.

 

[Yellow Jacket]

I think the way you guys are saying it is a little skewed or can be false information... IMO the 11 blade "has the potential" to make the most top end HP, but only at the appropriate pressure ratio of your application. Precision makes different 6 & 7 blade compressors that are designed for different applications. The 6 blade billets tend to "swallow" more air and run a slightly slower shaft speed than the 7 blade billets on the same charger.

IMO and based from my experiences, the 6 blades have the most potential for power, but have a "peakier" map and feel, 7 blade makes the best all around, and 11 blades broaden the map and have a "smoother" transition or power curve. 6 blades are getting so much lighter and spool up isn't suffering.

Fleece billet 63 vnt has a 7 blade design and they reduced the hub and but size, it has nearly the same blade length as the 4094 drop in 68mm billet compressor, but has less mass and mass from center is reduced, I've installed a few of these Fleece 63mm vnt's and they are amazing in my opinion. I just wish all compressor's were designed around this theory and that our 3.0 truck was up and running so I could afford to put a Fleece billet 63mm vnt on my DD truck, I'm tired of the lazy s366...

 

[Frankin_truck]

So what did you end up with? 6 blade?

 

[Hot COCOAL]

I thought the 11 blade design was implemented based around the requirements for the EGR system? Something about the 11 blade design creating more drive pressure so that when the EGR valve was open, exhaust flow or exhaust pressure would still be high enough to work through the EGR?

I am also considering getting a billet 6 blade compressor wheel for an LBZ turbo, and I am curious as to what to expect from using it.

Instead of building an engine out of "necessity" I've chosen to buy a used fully equipped running engine, and I'm wondering if just throwing a billet wheel in the stock turbo would be "good enough" for me, or if I should just get the new Danville unit (BMW 3794va)?

 

[LbzDMax07]

I thought the 11 blade design was implemented based around the requirements for the EGR system? Something about the 11 blade design creating more drive pressure so that when the EGR valve was open, exhaust flow or exhaust pressure would still be high enough to work through the EGR?

I am also considering getting a billet 6 blade compressor wheel for an LBZ turbo, and I am curious as to what to expect from using it.

Instead of building an engine out of "necessity" I've chosen to buy a used fully equipped running engine, and I'm wondering if just throwing a billet wheel in the stock turbo would be "good enough" for me, or if I should just get the new Danville unit (BMW 3794va)?

If its going to take the BMW 3794 to make the power you want more than likely you're going to be in the position you're currently in and that's needing a motor. The only thing i think is safe for these LBZs is stock trans tuning. If you really want the power build the motor IMO

 

[LbzDMax07]

Mike, are you making the switch to a billet wheel and the 87mm turbine at the same time or switching at different times? I think i read you was swapping to the 87 from the 83...

 

[minerigger]

I thought the 11 blade design was implemented based around the requirements for the EGR system? Something about the 11 blade design creating more drive pressure so that when the EGR valve was open, exhaust flow or exhaust pressure would still be high enough to work through the EGR?

I am also considering getting a billet 6 blade compressor wheel for an LBZ turbo, and I am curious as to what to expect from using it.

Instead of building an engine out of "necessity" I've chosen to buy a used fully equipped running engine, and I'm wondering if just throwing a billet wheel in the stock turbo would be "good enough" for me, or if I should just get the new Danville unit (BMW 3794va)?

The new turbo duh!

 

[juddski88]

I think the way you guys are saying it is a little skewed or can be false information... IMO the 11 blade "has the potential" to make the most top end HP, but only at the appropriate pressure ratio of your application. Precision makes different 6 & 7 blade compressors that are designed for different applications. The 6 blade billets tend to "swallow" more air and run a slightly slower shaft speed than the 7 blade billets on the same charger.

IMO and based from my experiences, the 6 blades have the most potential for power, but have a "peakier" map and feel, 7 blade makes the best all around, and 11 blades broaden the map and have a "smoother" transition or power curve. 6 blades are getting so much lighter and spool up isn't suffering.

Fleece billet 63 vnt has a 7 blade design and they reduced the hub and but size, it has nearly the same blade length as the 4094 drop in 68mm billet compressor, but has less mass and mass from center is reduced, I've installed a few of these Fleece 63mm vnt's and they are amazing in my opinion. I just wish all compressor's were designed around this theory and that our 3.0 truck was up and running so I could afford to put a Fleece billet 63mm vnt on my DD truck, I'm tired of the lazy s366...

just about anything is better than the 366! haha

I'm installing both a S468fmw and revised DTS 63.5VVT in the next two weeks, both on trucks that tow and do everything else a fun "stock" duramax does. I already know the DTS charger rocks, but I am very interested in comparing the drivability of these two...the two owners are in a competition too, lol, so it should be fun.

 

[juddski88]

this thread may offer a bit of help to the OP too
http://www.competitiondiesel.com/forums/showthread.php?t=156570&page=2

 

[mike diesel]

So what did you end up with? 6 blade?

I sent him an email said I wanted a 6 blade, extended tip, extended height wheel. He hasnt responded yet. But prior to that he told me whatever options I want, he will do.

Mike, are you making the switch to a billet wheel and the 87mm turbine at the same time or switching at different times? I think i read you was swapping to the 87 from the 83...

At this time I wont be going to an 87mm turbine. Whenever I decide to pull my trans so I can send my converter out for a restall is probably when I will send the turbo in for an 87mm upgrade.

 

[PACougar]

just about anything is better than the 366! haha

I'm installing both a S468fmw and revised DTS 63.5VVT in the next two weeks, both on trucks that tow and do everything else a fun "stock" duramax does. I already know the DTS charger rocks, but I am very interested in comparing the drivability of these two...the two owners are in a competition too, lol, so it should be fun.

Pleaser post about it, I really want to do one of the S468 for my new toy/tow vehicle. What size turbine are you guys going with?

 

[mike diesel]

this thread may offer a bit of help to the OP too
http://www.competitiondiesel.com/forums/showthread.php?t=156570&page=2

Dang near answered every question I had. Thanks

 

[juddski88]

Pleaser post about it, I really want to do one of the S468 for my new toy/tow vehicle. What size turbine are you guys going with?

It will be an 83mm wheel with a 1.0 housing on the S468FMW. If it was less of a daily driver I would've definitely gotten the 1.10 housing. The coolest thing about this charger to me is the value: for what you pay you get a charger that is 800hp capable, has a BW race cover, and daily drives better than the crap S366 that everyone on the forums seems to love so much.

The DTS charger has a 71mm turbine wheel (same as the newer Fleece VVTs) which I haven't tried yet, the one we put on our sponsored workstock truck has a 68mm turbine wheel and the thing is an ANIMAL.