GTX3071R or GTX3076R - 2.5 Litre?
#1
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GTX3071R or GTX3076R - 2.5 Litre?
I'm looking at a GTX3071R with a .82A/R hotside for my 2.5 litre which will be running a N/A head with 2mm oversize valves, cam & standalone. I'm retaining hydraulic lifters & want to maintain the stock rev range.
Should I be looking at the GTX3076R with a .82A/R instead or will this be too laggy?
The guys at the turbo shop recommended a .82 hotside on the GTX3071R stating that a .63 would strangle it too much.
I want the car to be streetable with the odd trackday. I suppose I'm wanting at least the mid-range response of the stock car but with the added bonus of much more top-end.
My goal - something which can scare a GT3 for a few laps on a DE day & then drive home!
Should I be looking at the GTX3076R with a .82A/R instead or will this be too laggy?
The guys at the turbo shop recommended a .82 hotside on the GTX3071R stating that a .63 would strangle it too much.
I want the car to be streetable with the odd trackday. I suppose I'm wanting at least the mid-range response of the stock car but with the added bonus of much more top-end.
My goal - something which can scare a GT3 for a few laps on a DE day & then drive home!
#5
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From personal experience with a GT3076 .63 and .82 on a 2.5L with n/a head, cam, exhaust, front mount...but not bigger valves...I found that the .63 was a great street and occasional track turbo and the .82 was more a track turbo running a bit of boost. Depending on how high you want to rev and how much boost you want to run would help in advising you. Maybe the 71 with an .82 might just be a good option.
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I'm looking at running modest boost in the interests of durability/reliability but perhaps a little more than the norm, say 18-22 PSI.
I'm looking to run to the stock rev limit but will be running a SFR front mount, SFR N/A head, cam & Motec & the appropriate fueling system.
There's then the the matter of the cross-over between a 71R running a .82A/R & 76R running a .63 hotside.
Will the 71R give me plenty of head-room for my set-up?
I'm looking to run to the stock rev limit but will be running a SFR front mount, SFR N/A head, cam & Motec & the appropriate fueling system.
There's then the the matter of the cross-over between a 71R running a .82A/R & 76R running a .63 hotside.
Will the 71R give me plenty of head-room for my set-up?
#7
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I would think so. You have to google up those turbos and read what other's are getting. There's a pretty good write up on another forum, EVO or Scuby I think. Have to dig around a bit. Not a lot of experience on the GTX series out there yet.
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GT vs GTX
I've posted this before but these guys pulled some dyno runs with gt and gtx turbos and .63 vs .82 runs. some good info there. i havnt searched for any other info latley yet.
I've posted this before but these guys pulled some dyno runs with gt and gtx turbos and .63 vs .82 runs. some good info there. i havnt searched for any other info latley yet.
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The entire GTX line is pretty much unattainable. Be prepared for a long wait if you want one.
I have an interesting alternative I am trying out for a 3.0 engine – it’s a GT35 with a new billet inducer wheel and a Tial hot side housing that is supposed to be similar to the GTX35 with a little better spool up……and its available now (if you have the right connections!)
I have an interesting alternative I am trying out for a 3.0 engine – it’s a GT35 with a new billet inducer wheel and a Tial hot side housing that is supposed to be similar to the GTX35 with a little better spool up……and its available now (if you have the right connections!)
#10
I have an interesting alternative I am trying out for a 3.0 engine – it’s a GT35 with a new billet inducer wheel and a Tial hot side housing that is supposed to be similar to the GTX35 with a little better spool up……and its available now (if you have the right connections!)
Pics?
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BW EFR 7670 & 8374
Chris, my turbo guys reiterated your comments regarding availability of the GTXs, but as I'm not in a hurry that's not an issue for me.
They did recommend I look at the Borg Warner EFR turbos which they felt had a number of class-leading features & were pretty cutting edge.
I'm assuming the EFR 7670 (rated at 375 - 600 bhp) is comparable to the GTX3076R but the EFR 8374 (475 - 750 bhp) is getting up there in exducer & turbine wheel diameter for a tuned 2.5 litre.
The EFRs have a T4 mounting flange, internal wastegates & BOVs, ceramic dual BBs, stainles steel turbine housing, water cooled & can have a speed senor fitted & a V-Band outlet.
Has anyone had any feedback on these units?
Are their physical dimensions feasible for our cars?
Tim
They did recommend I look at the Borg Warner EFR turbos which they felt had a number of class-leading features & were pretty cutting edge.
I'm assuming the EFR 7670 (rated at 375 - 600 bhp) is comparable to the GTX3076R but the EFR 8374 (475 - 750 bhp) is getting up there in exducer & turbine wheel diameter for a tuned 2.5 litre.
The EFRs have a T4 mounting flange, internal wastegates & BOVs, ceramic dual BBs, stainles steel turbine housing, water cooled & can have a speed senor fitted & a V-Band outlet.
Has anyone had any feedback on these units?
Are their physical dimensions feasible for our cars?
Tim
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Paulyy, thanks for the link to the Scooby site. Perrin seemed to think (on a 2.5 litre) that the spool rates of the 71R & the 76R would be comparable given they share the same turbine wheel, even though the 71's compressor wheel is probably marginally lighter, he felt this would make an insignificant difference.
His reasoning was that if the spool for the 71 & 76 were almost the same you'd be better to go for the 76 for more headroom.
His reasoning was that if the spool for the 71 & 76 were almost the same you'd be better to go for the 76 for more headroom.
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Paulyy, thanks for the link to the Scooby site. Perrin seemed to think (on a 2.5 litre) that the spool rates of the 71R & the 76R would be comparable given they share the same turbine wheel, even though the 71's compressor wheel is probably marginally lighter, he felt this would make an insignificant difference.
His reasoning was that if the spool for the 71 & 76 were almost the same you'd be better to go for the 76 for more headroom.
His reasoning was that if the spool for the 71 & 76 were almost the same you'd be better to go for the 76 for more headroom.
i actualy left london today and now in paris. but yes i am not looking foward to that flight home.