Any one running a 6870 precision turbo on a stage 2

3 bolt GEE M racing. I figure going v band from 3 bolt is easier than 4 bolt.
After I cut off the flange for the 3 Bolt I measured and the whole is 2 1/8 . The hole for the V band that you weld on to your header is 2 5/8 not sure how much of a difference this is going to make with flow probably not much at all being two different sizes like that .I probably should have gotten a step up in size and welded that first onto my header then to the V band. Yes I know it's not quite centered LOL but it's flat lol
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Dare I ask how much that housing was?
Gulp $700 and one kidney that's with the kit for the V band stainless steel and clamps .for the housing itself I don't know. I got the V Band for the header and one for my downpipe all stainless steel

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If all goes well, i will have back pressure reading for the 6870 as well as the 7168. I will also have hp and boost comparisons.
 
I'll be running a 7168 soon what kind back pressure r u seeing ?
 
I've got a 6870 3 bolt. My car is going to a chassis shop in two weeks, after that I'll be taking it to the track to test and record backpressure on it. I'll make my own thread and post up my results. I've got a RJC 315 fmic and I plan on buying another transducer soon that way I can log the pressure drop on it. I'll post those results too. I got an old ATR FMIC sitting in the garage, I have to make new pipes for it but plan on doing that maybe in June/July, i'll post the results on it also if anyone cares about it.
 
It takes 45lbs co2 to make 31psi boost with a 4lbs spring in the gate. Boost in the low 20s, it is 1:1. The back pressure climbs after that.
That's good to know. I'm running a 6466 right now and it's a bit small for my combo. I made a 132mph pass on a very slippery track, I think a 2.1 60 foot, something like that. Ran an 11.0 nonetheless. That was on 23 psi if I remember correctly. For experiment, I cranked it up higher and didn't gain anything after 23 psi. I have 4.6 liters, so a 6870 would probably feed this baby quite well. I'd love to borrow one for experimentation.
 
That's good to know. I'm running a 6466 right now and it's a bit small for my combo. I made a 132mph pass on a very slippery track, I think a 2.1 60 foot, something like that. Ran an 11.0 nonetheless. That was on 23 psi if I remember correctly. For experiment, I cranked it up higher and didn't gain anything after 23 psi. I have 4.6 liters, so a 6870 would probably feed this baby quite well. I'd love to borrow one for experimentation.

Toomanymodz with the 6870 4 bolt housing at 21 psi i ran 9.87 @ 139 with a on center stage 2 4.1 with Champion heads. The 6870 is AWESOME, for the street it spools instantly and pulls like crazy. I run my car at 21psi and alky on the street and it is truly a full ride.
 
Toomanymodz with the 6870 4 bolt housing at 21 psi i ran 9.87 @ 139 with a on center stage 2 4.1 with Champion heads. The 6870 is AWESOME, for the street it spools instantly and pulls like crazy. I run my car at 21psi and alky on the street and it is truly a full ride.
That's awesome. I'm on a budget, so a 4 bolt deal is out of the question. I want to keep the same downpipe too. I figure my current combo should trap close to 135 if I open the dump and can get the boost more stable. The 132 pass was through the exhaust. It likes to fall off as the rpm increases, so the graph looks like a saw-tooth. I notice that the boost is more stable with an open dump. Exhaust pressure is something I will look into.

I've done some tests on the street and at 21 psi and 18 degrees of timing, it went 70 - 120 in 5.6 seconds through the exhaust. With no other changes except opening the exhaust dump it did the same in only 5.2 seconds (boost gained 1 psi to 22 on its own). I'd love to see what this dog can do with a 6870.
 
That's awesome. I'm on a budget, so a 4 bolt deal is out of the question. I want to keep the same downpipe too. I figure my current combo should trap close to 135 if I open the dump and can get the boost more stable. The 132 pass was through the exhaust. It likes to fall off as the rpm increases, so the graph looks like a saw-tooth. I notice that the boost is more stable with an open dump. Exhaust pressure is something I will look into.

I've done some tests on the street and at 21 psi and 18 degrees of timing, it went 70 - 120 in 5.6 seconds through the exhaust. With no other changes except opening the exhaust dump it did the same in only 5.2 seconds (boost gained 1 psi to 22 on its own). I'd love to see what this dog can do with a 6870.


I understand budgets as these cars have their hand in your wallet all the time, that said the 6870 really acts like a normally aspirated car instant explosive power. I ran 28psi at the track last November and got a 9.4 @ 146, just a great all around turbo. Good luck with your combo.
 
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