Question: AVNT4094/vs cheetah ?

[2500HeavyDuty]

good read, anyone else notice that cheetah is misspelled in the thread title?

 

[whitetrash21]

the VVT can close the vains and use drive pressure to open the EGR valve . instead of having to have a vacume pump to do the job , the cummins just got a vvt on the 6.7 and a EGR came with it , same as the lly,lbz,lmm , and the 6.0 powerstroke . some lb7's got the egr and they had vacume pumps but only the cali trucks .

Had one of those on my 03. Hated that friggin pump. Lost 4 of them in 25k miles. GM kept replacing them, saying they fixed it right up till it ran out the warranty.

Hopefully with what I read, this wont be a problem on this truck.

 

[McRat]

good read, anyone else notice that cheetah is misspelled in the thread title?

He got "vs" right; .500 average is better than Major League players.

 

[knagel]

I will have dyno #'s from my new engine build sometime next week. It will be break in #'s tho. This will be with a fully built SoCal engine with 60% sticks and a 4094vn. And yes..... I have my tranny built now too

I think the cheetah and 4094 come down to personal preference. I went with the 4094 because maps were avaiable, Dan at PPE is usually always available and very helpful, this is a NEW trubo, not rebuilt and it had a factory warrenty.

My 2 cents.

Kevin

 

[Fingers]

The pedigree of the VNT did not start with anything related to EGR, but it did facilitate it. The vane plan form for the LLY, LBZ and LMM turbos are all the same, and are geared to always generate more drive pressure than boost.That is different than the originals that had nearly knife thin vanes, and very low drive pressures. The plan form on the 4094 has significantly thinner vanes, as does my design. Both are limited by the diameter of the pivot rod.

The AVNTs expand the usable range for any compressor wheel. The drive pressure spike to spin a 104mm will be interesting to map. Especially with a set of my 3'rd generation vanes. Maybe this winter....

I think a waste gate on a VNT turbo is not a bad idea. At some vane angle, you are generating drive pressure without any gains in boost. At that point, you need to start dumping the excess back pressure. JMO

 

[Brayden]

Our 71.5mm is a Garrett Wheel.

As for durability all of our turbo's feature AVNT turbines now. I will still build the non AVNT turbo's for race applications because the turbine flows more than the AVNT offerings available now.

AFAIK the 71.5mm Cheetah is a BW K31 (A5K) wheel. Last I knew the 68 and 71.5mm cheetahs both use GT4088 turbine wheels in a stock LBZ housing with stock LBZ vanes. The 68mm uses a GT 4094 compressor in a machined stock compressor housing.

Might as well bring in the Danville 68mm stage 2 turbo as well. It is also a 4094 comp wheel in a machined stock housing. He uses the turbine from the AVNT 37 with custom vanes from fingers in an LLY turbine housing.

Lastly the AVNT 4094 uses a 4094 comp wheel in a housing that was made for it. I has a larger turbine than the AVNT 37, but one that was designed to be in an AVNT turbo. The compressor map is the same as the GT4094 but the exhaust side is more restrictive and therefore you won't get as much power out of it as you will a GT4094R.

They are all direct bolt on for LLY and newer trucks and now with the Fleece boost controller will also bolt onto LB7s. They all make a similar whistle to what the Cheetah does. And the turbine side is the limiting factor on all of them IMO. My bet is that on a single CP3 you will likely make very close to the same power on all 3 of the 68mm VVTs. Once you are pushing the limits of what the turbines can flow is when you will start to see which one has the best flowing turbine and makes the most max effort power. You can't however use the same tuning to test all 3, with the differences in the turbine side you would have to test and tune on each to get your vane position tables right. My best guess is that the Danville and Garrett models will be more durable that a Cheetah.

Ideally Garrett would develop and release a variable GT42 sized turbo with a much more free flowing turbine side.

 

[Brayden]

The turbine info is correct but the compressor is not a BW on the 71.5mm..

Just for info's sake about our chargers vs the rest.. Nobody has come close to our output on a VNT turbo in the quarter mile or hp output on the dyno.

Thank you as thats most of the info i was looking for see pat it wasent that hard.

Thanks for info! I didn't mean to imply that the AVNT40 used the same PN turbine wheel just they are the same size.

Wish I had the time and money to find the limits of the AVNT4094. I'm convinced it will make the power the normal 4094 will.

AFAIK the 71.5mm Cheetah is a BW K31 (A5K) wheel. Last I knew the 68 and 71.5mm cheetahs both use GT4088 turbine wheels in a stock LBZ housing with stock LBZ vanes. The 68mm uses a GT 4094 compressor in a machined stock compressor housing.

Might as well bring in the Danville 68mm stage 2 turbo as well. It is also a 4094 comp wheel in a machined stock housing. He uses the turbine from the AVNT 37 with custom vanes from fingers in an LLY turbine housing.

Lastly the AVNT 4094 uses a 4094 comp wheel in a housing that was made for it. I has a larger turbine than the AVNT 37, but one that was designed to be in an AVNT turbo. The compressor map is the same as the GT4094 but the exhaust side is more restrictive and therefore you won't get as much power out of it as you will a GT4094R.

They are all direct bolt on for LLY and newer trucks and now with the Fleece boost controller will also bolt onto LB7s. They all make a similar whistle to what the Cheetah does. And the turbine side is the limiting factor on all of them IMO. My bet is that on a single CP3 you will likely make very close to the same power on all 3 of the 68mm VVTs. Once you are pushing the limits of what the turbines can flow is when you will start to see which one has the best flowing turbine and makes the most max effort power. You can't however use the same tuning to test all 3, with the differences in the turbine side you would have to test and tune on each to get your vane position tables right. My best guess is that the Danville and Garrett models will be more durable that a Cheetah.

Ideally Garrett would develop and release a variable GT42 sized turbo with a much more free flowing turbine side.

The 40-94r ran verry good on my truck and ran the same egts as my stock turbo but with a tune with more fuell and more power. Tuneing def has alot to do with egts and other things as i have found out.
the cheetha had the highest egts out of all three turbos but still ran verry strong. and was close with the 40-94. the 40-94 just seemed to have a little something more to it.

If this new avnt works like the 40-94r does then i think it would be a really great option. only time will tell thoe. A gt 42 avnt would be awesome if the could manage the DP and egts

 

[Brayden]

I have to agree, untill some one shows me different anyway. with a 68mm compressor lack of air cant be the cause for the high EGT's , so the only other thing besides lack of air to drive up EGT's is drive pressure . While i agree that more timming can maybe knock the heat down a bit , it is not the fix IMOP just a band aid . But i have never owned a 4094 or tested drive pressure with one , just have theroys in my head LOL

I wouldn't say that drive pressure is the only thing to drive up EGT's.. that's far from true.. Way too many variables. Timing affects EGT's... Pulsewidth drives EGT's more than anything, IMO.

 

[Dan@PPE]

The turbine info is correct but the compressor is not a BW on the 71.5mm..

Just for info's sake about our chargers vs the rest.. Nobody has come close to our output on a VNT turbo in the quarter mile or hp output on the dyno.

What are the numbers to beat???

 

[Brayden]

I have a 102mm VNT from an EGR Detroit Diesel that someday I hope to play with. Big Dipper found it on Ebay and I bought it. But it's T6 and HUGE. 1.74 exh A/R.

I have one as well They're used on the DDEC V motors. They are decent, but I've got a design that should work as well with less bulk and electric/hydraulic controls.

 

[Brayden]

What are the numbers to beat???

11.55 @ 116.9 in the quarter on a stock appearing VNT.

The truck dyno'd 730hp and had more in it.. because the first run with that tune did 11.71 @ the track. I upped the pw and got it down to 11.55. I'd say it was north of 750 to do that.. especially with the street tires, and 20" wheels.

 

[TrentNell]

I wouldn't say that drive pressure is the only thing to drive up EGT's.. that's far from true.. Way too many variables. Timing affects EGT's... Pulsewidth drives EGT's more than anything, IMO.

Agreed but you have to admit that guys with 4094's have ALOT higher EGT's then they should have . Have you ever tested DP on one ? I have been wanting some one to test one just to satisfy my curiousity

And a few guys including KevinL have ran the same tunning with a stock lb7 charger with lower egt's ?

 

[SteveFord]

11.55 @ 116.9 in the quarter on a stock appearing VNT.

The truck dyno'd 730hp and had more in it.. because the first run with that tune did 11.71 @ the track. I upped the pw and got it down to 11.55. I'd say it was north of 750 to do that.. especially with the street tires, and 20" wheels.

What size is the 71.5mm. Is it a 2.8 or a 3.0? Also what size is the avnt4094? Sorry for the multiple questions but have you got any testing done yet with your 4094?? Pm me if you want on this if you feel needed to.

 

[Brayden]

Agreed but you have to admit that guys with 4094's have ALOT higher EGT's then they should have . Have you ever tested DP on one ? I have been wanting some one to test one just to satisfy my curiousity

And a few guys including KevinL have ran the same tunning with a stock lb7 charger with lower egt's ?

I agree with you that the 4094 in it's fixed geometry configuration isn't the best setup. If you look at the equivalent sized S300 66mm inducer there is a much larger turbine (Drive hp). IMO the 4094 doesn't have a big enough turbine. The 4094VA won't suffer from the spool up issues but will still have issues with the turbine exducer at high hp 700+

 

[Brayden]

What size is the 71.5mm. Is it a 2.8 or a 3.0? Also what size is the avnt4094? Sorry for the multiple questions but have you got any testing done yet with your 4094?? Pm me if you want on this if you feel needed to.

I've sent over 10 of them out and they're working great.

The 71.5mm is 2.8"

 

[SteveFord]

I've sent over 10 of them out and they're working great.

The 71.5mm is 2.8"

Thanks for the info. Anyone here in Iowa running one of the 4094's I can talk to or see?

 

[Brayden]

Nobody in Iowa that I know of... Come down to our pull next weekend and you'll probably see some

 

[Kat]

Thanks for the info. Anyone here in Iowa running one of the 4094's I can talk to or see?

See post #64 Kevin is in Central, Iowa

Don't know where that is in relation to where you are at.

 

[Brayden]

I've got a couple people driving 5-6 hours to come pull.... Us truck puller types are CRAZY

 

[SteveFord]

See post #64 Kevin is in Central, Iowa

Don't know where that is in relation to where you are at.

Thanks Kat but I should have made my post more clear. I meant as in a cheetah 4094. I got video of Kevin from a few months ago when he got everything on his truck and was very impressed with the Garrett unit:coolspot:.