What turbo size???
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On The Tree
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What turbo size??? Ok so I'm looking into going single turbo kit on my goat. It's an ls1, throwing in some compstar h beams, and diamond pistons. Anyway, just curious on what turbo sizes you guys recommend for a 347. I'm looking to make a max of 650whp. Would like to either go borg or precision but any advice is welcome. I'm just trying to make sure I do my build properly.
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Joined: Mar 2014
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From: Ohio
I agree with him, that's a good Precision for a stock cube LS1 wanting to make 650+. From there larger or smaller is simply preference.
As for Borg, the small wheel S475 is like $650 and probably makes a bit more power (not to mention more reliable), but they're physically huge and hard to fit in a GTO.
As for Borg, the small wheel S475 is like $650 and probably makes a bit more power (not to mention more reliable), but they're physically huge and hard to fit in a GTO.
On The Tree
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7675 all day. it will also give you room to grow a little. I know you only want 650 right now. but that 7675 will do over 700 if you ever want a little more power. I know I started out just wanting 400 rwhp ten years ago, now I'm heading towards 800rw and wanting more haha
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From: Ohio
Why do you want 'at least' a 76mm compressor? My 74mm is making huge power, and I haven't even pushed it to the point where I need more than cheap pump gas.
I'd stay away from the 7668 on a 5.7. Turbine side is just a little small.
I'd stay away from the 7668 on a 5.7. Turbine side is just a little small.
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Lag can be helped by other things besides turbo sizing. But you said you wanted at least a 76mm and then said the 7675 sounded too big. They are one in the same.
The 7675 is a little expensive for mild power levels like that and a 7668 can make the power you want just not much more. For a little more money you can get a 7875 from Turbonetics and it will make plenty of power and support more later.
For less money you can get the Chinese copy of the 7875 from on3 and still meet you goal for like half the price.
The 7675 is a little expensive for mild power levels like that and a 7668 can make the power you want just not much more. For a little more money you can get a 7875 from Turbonetics and it will make plenty of power and support more later.
For less money you can get the Chinese copy of the 7875 from on3 and still meet you goal for like half the price.
P-Trim 66mm T4 Turbo will get your goal just maybe
PT 6266 CEA get you your 650+ rwhp not much left yet would be ready for boost always..
PT 6766 CEA turbo, a bit overkill for 650 rwhp yet would be responsive and have room to grow..about 800 rwhp capable
You will probably find with a capable bottom end your going to be wanting more of that feeling Boost gives!! enjoy whatever you do....tune wisely and patience with timing advancing....its a killer!
PT 6266 CEA get you your 650+ rwhp not much left yet would be ready for boost always..
PT 6766 CEA turbo, a bit overkill for 650 rwhp yet would be responsive and have room to grow..about 800 rwhp capable
You will probably find with a capable bottom end your going to be wanting more of that feeling Boost gives!! enjoy whatever you do....tune wisely and patience with timing advancing....its a killer!
Last edited by Rudy72; Mar 3, 2016 at 01:42 AM. Reason: spelling
Thread Starter
On The Tree
Joined: Aug 2012
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Lag can be helped by other things besides turbo sizing. But you said you wanted at least a 76mm and then said the 7675 sounded too big. They are one in the same.
The 7675 is a little expensive for mild power levels like that and a 7668 can make the power you want just not much more. For a little more money you can get a 7875 from Turbonetics and it will make plenty of power and support more later.
For less money you can get the Chinese copy of the 7875 from on3 and still meet you goal for like half the price.
The 7675 is a little expensive for mild power levels like that and a 7668 can make the power you want just not much more. For a little more money you can get a 7875 from Turbonetics and it will make plenty of power and support more later.
For less money you can get the Chinese copy of the 7875 from on3 and still meet you goal for like half the price.
I guess what I'm saying is the 7675 is good for 1000hp. Im shooting for 650whp. When i read the numbers that's why i was like it seems a bit big for my power. I mean i guess i could add a quickspool valve. I don't know? I guess i just really don't understand what you need as far as turbine side and such for it to be a sufficient turbo for a v8. Thank you for information though i appreciate it!
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Problem is you're just taking the compressor into consideration. Too small of a turbine will be a restriction on the exhaust. I would recommend looking at a minimum 80mm to 87mm turbine wheel single that will be very responsive but not restrictive. We had excellent results with a Master Power 76mm GT45 1.05 A/R ex 6-bolt exhaust outlet flange. Compressor and turbine wheel diminsions are very close to the Precision PT7675. I've seen Chinese copies on Ebay and a genuine Master Power made in Brazil can be bought for around $700 new. 69mm Borg Warner S300SX-E will support 900+ on the compressor but will choke the exhaust before that even with a 1.00 exhaust housing. Keep in mind the S400 Borg Warner compressor housings are huge in comparison to any of the Garrett copied compressor housings.
Thread Starter
On The Tree
Joined: Aug 2012
Posts: 163
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Problem is you're just taking the compressor into consideration. Too small of a turbine will be a restriction on the exhaust. I would recommend looking at a minimum 80mm to 87mm turbine wheel single that will be very responsive but not restrictive. We had excellent results with a Master Power 76mm GT45 1.05 A/R ex 6-bolt exhaust outlet flange. Compressor and turbine wheel diminsions are very close to the Precision PT7675. I've seen Chinese copies on Ebay and a genuine Master Power made in Brazil can be bought for around $700 new. 69mm Borg Warner S300SX-E will support 900+ on the compressor but will choke the exhaust before that even with a 1.00 exhaust housing. Keep in mind the S400 Borg Warner compressor housings are huge in comparison to any of the Garrett copied compressor housings.
On3 makes a "clone" of that turbo for a huge amount less. I say it like that because a few on here talked about the on3 possibly using the same parts as the turbonetics turbo it's just assembled here like the name brand one is.
