Single Turbo RX-7's Questions about all aspects of single turbo setups.

Should I ???

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Old 01-24-07, 02:14 PM
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Talking Should I ???

As some of you might know , I had a slight ******' problem with my monster FMIC and the seals on my rear rotor . I am pulling the motor to rectify this soon . Lately I have found that I've been having a lot of thoughts about a nice BIG FAT single ! like a GT42R , 45R or the 47R ! , should I chuck my twins for this ? , would my set-up be any better with a large , sorry massive blower ? how do you think it'll behave on the street , keep in mind , my motor/port combo would make the twins boost 20+ psi before 3500 rpm !
Old 01-24-07, 02:26 PM
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I say chuck the twins, go SINGLE!!! There's a guy in the for sale section selling a almost brand new a-spec 500r kit, looks sweet. Get it....I hear response and power on that puppy is pretty darn good.

GL on your decision.
Old 01-24-07, 02:41 PM
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keep the twins...sort out issues.

the air was too cold...and dense, and that's what popped your motor? I have never really heard of an IC causing a motor failure.
Old 01-24-07, 02:46 PM
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Well apart from my new koyo NFlo rad and EWP , thats the only other thing I changed , thats why its the first suspect ! ya know , maybe I shoulda done a poll ?
Old 01-25-07, 07:14 PM
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Anyone else ?
Old 01-25-07, 08:21 PM
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Go with a gt42r or something a little bigger. I will shortly see how my modified
t-88 will spool on an agrressive bridgeport. The nice thing with a big single is that it's simple and if you want you can run 38psi or 14psi and lag really is not bad even at 4700rpm. Just my 2 cents
Old 01-25-07, 08:41 PM
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big single you won't see 20psi until 4500rpm or so

TWINS!
Old 01-25-07, 08:51 PM
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True , but what about the overall flow and back presure ? , although its two turbines , its a pair of small turbine wheels .
Old 01-25-07, 10:42 PM
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If you're really seeing 20 psi by 3500 rpms, I say give the twins another chance.
Old 01-26-07, 07:03 PM
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twin turbos are just like twin brunettes....Sexy :)

stick with the twins! I have been collecting parts for a twin to4e setup and have been watching your thread for a while.

just got both turbos, and wastegates, and am now collecting fuel system parts, and pipeing.

kenn
Old 01-31-07, 08:23 AM
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gt47 and make it sing!!!!!! but i must admit the twins are badass.
Old 01-31-07, 08:51 AM
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Like Rich said, if you're making that type of boost by 3,500 rpms, I'd stay with them. There is no way a GT42 would be making that amount of boost by that RPM. Sort out the issues with the twins, and you can have pride in something you built youself. But on the other hand, if you're getting tired of allways working on your car, you might want to consider going single. I say stay with the twins. CJ
Old 01-31-07, 02:26 PM
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Stick with your twin setup, singles turbo FD's are more common now than even stock ones.

-S-
Old 01-31-07, 04:01 PM
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pm'd you
Old 02-01-07, 02:24 PM
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Originally Posted by Zero R
Stick with your twin setup, singles turbo FD's are more common now than even stock ones.

-S-
This mean you are going to stop selling kits?
Old 02-02-07, 07:09 PM
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Ok , heres what ........ , based on Howards pm and my long time suspicions , it seems that the 3071 turbine a/r's are too small for my motor . I already looked at upping to a larger 0.82 of 1.06 , but these housings cost $377 and $360 respectively ! and thats from precision !
I have decided to stay with the twins but sell the 3071's and upgrade to the 3076 model , with .82 a/r turbines (the turbine wheel size on the '71 and '76 are the same) , heres the dilema , my friend , who is also my supplier is trying to convince me to go with a pair of GT35R's and stay with the 0.63 a/r turbines , he says the 35's have a larger size turbine wheel , so they would be great in the .63 housings . What do you think , I am confident , based to the response of the 3071's and my other friends GT45 on his bridged motor , that I would be able to spool them , but I am not sure about if there would be any surging issues at low rpm / load conditions , any of the turbo gurus have any idea ?
Old 02-03-07, 11:02 AM
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a gt35 makes 60 pounds per minute of air. times 2 is 120 pounds.

120*10/1.3= 923 rotary rear wheel hp.

that's what two gt35s would do if properly spooled and supported w fuel etc etc.

what is it that you are trying to do w your car?

Mike Haut built his 3 rotor fd very nicely and it was turbo limited as to hp. as such, he had early spool and an airflow-limited 630 rwhp from 4000 thru 7000. at 630 he concluded that the car was undriveable. you could go sideways at any speed.

my car is making over 500 (undynoed until march). i run 18 X10 rears w 285s at 25 psi air pressure. i have 53% rear weight. w 88 pounds of turbos my car went sideways at 79 mph rolling onto the throttle (TPS 59%) in 3rd gear at 10.5 AFR at 17 psi.

so what do you want w 120 pounds of turbos?

howard coleman
Old 02-03-07, 11:12 AM
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Hm, that brings a bit of perspective into this thread
Old 02-03-07, 05:54 PM
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Originally Posted by GoodfellaFD3S
Hm, that brings a bit of perspective into this thread

Whats the need for all that ? I'm just asking a question , I'm just trying to be find ou all I can before I spend the money , jeezz..............!
If the car goes sideways or in a circle , i'll deal with that , what ever I decide to do with the car , if its a drag , road race or , street or just a big toy really has nothing to do with it !
I'm just asking if a ported 13B will be able to handle a pair of 35's without surging and eventually failing , thats all I want to know for now , we can talk about the rest later !
Old 02-03-07, 05:57 PM
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Originally Posted by howard coleman
a gt35 makes 60 pounds per minute of air. times 2 is 120 pounds.

120*10/1.3= 923 rotary rear wheel hp.

that's what two gt35s would do if properly spooled and supported w fuel etc etc.

what is it that you are trying to do w your car?

Mike Haut built his 3 rotor fd very nicely and it was turbo limited as to hp. as such, he had early spool and an airflow-limited 630 rwhp from 4000 thru 7000. at 630 he concluded that the car was undriveable. you could go sideways at any speed.

my car is making over 500 (undynoed until march). i run 18 X10 rears w 285s at 25 psi air pressure. i have 53% rear weight. w 88 pounds of turbos my car went sideways at 79 mph rolling onto the throttle (TPS 59%) in 3rd gear at 10.5 AFR at 17 psi.

so what do you want w 120 pounds of turbos?

howard coleman

Howard , thanks for all your advice and help so far , but it seems you are more concerned about what I'll do with ALL THAT POWER , than trying to answer what I asked , Its all right I'll figure it out on my own .




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