Would this be possible? (Keeping boost down idea)
03-07-02, 07:07 AM
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Would this be possible? (Keeping boost down idea)
Ok, i've noticed a lot of TII people don't have ECUs or upgraded turbos. Ideally speaking, and the general consensus, is not to run more than 10-12 on the factory turbo. So how to limit the flow going into the engine, so that the turbo never sees more than 10-12 psi. Setup something like this:
Full exhaust or DP, Hiflo cat, catback
Intake
FCD (debateable, not in this thread though please!
)
Gauges out the wawa
Could it be possible by using a smaller piece of pipe in the TID or using a 90 degree bend or two, to keep the boost levels down? Crazy q I know...but i've been curious for some time now.
Joe
Full exhaust or DP, Hiflo cat, catback
Intake
FCD (debateable, not in this thread though please!
)Gauges out the wawa
Could it be possible by using a smaller piece of pipe in the TID or using a 90 degree bend or two, to keep the boost levels down? Crazy q I know...but i've been curious for some time now.
Joe
I'm still trying to bring it up...
03-07-02, 11:14 AM
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i played with that with mine.
the intake duct has a big impact on the power curve.
a small diameter duct will give you tons of low end and throttle response, but you lose a bunch off the top.
a big duct will give you more top but it has less response. i only played with a 2" and a 3" duct i think 2.5 would give a good mix of both.
another thing to do to keep boost down is to leave the stock airbox and some sort of main cat in the car
mike
the intake duct has a big impact on the power curve.
a small diameter duct will give you tons of low end and throttle response, but you lose a bunch off the top.
a big duct will give you more top but it has less response. i only played with a 2" and a 3" duct i think 2.5 would give a good mix of both.
another thing to do to keep boost down is to leave the stock airbox and some sort of main cat in the car
mike
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03-07-02, 01:26 PM
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why don't you try a manual boost controller,,buy one made out of brass fitting off of ebay for $12 and set it and forget it,,if the boost goes up the waste gate comes open,,pretty simple
03-07-02, 02:03 PM
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Originally posted by LLADNAR
why don't you try a manual boost controller,,buy one made out of brass fitting off of ebay for $12 and set it and forget it,,if the boost goes up the waste gate comes open,,pretty simple
why don't you try a manual boost controller,,buy one made out of brass fitting off of ebay for $12 and set it and forget it,,if the boost goes up the waste gate comes open,,pretty simple
NO BOOST CONTROLLER CAN LOWER BOOST!
It can only raise it!
Originally posted by j9fd3s
a small diameter duct will give you tons of low end and throttle response, but you lose a bunch off the top.
a big duct will give you more top but it has less response
a small diameter duct will give you tons of low end and throttle response, but you lose a bunch off the top.
a big duct will give you more top but it has less response
03-07-02, 02:31 PM
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i think it had something to do with the velocity of the air in the tube. i also didnt use the the stock tube and a 3". i have a 3" pipe and a 2" pipe.
mike
mike
03-07-02, 02:52 PM
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Originally posted by j9fd3s
i think it had something to do with the velocity of the air in the tube
i think it had something to do with the velocity of the air in the tube
03-07-02, 03:19 PM
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i have to disagree with you about the boost controller,,,it works on a check ball and spring you could set it to release at 1 psi if you wanted by removing some of the tension on the spring thus letting the waste gate open much earlier
03-07-02, 03:27 PM
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Originally posted by LLADNAR
i have to disagree with you about the boost controller,,,it works on a check ball and spring you could set it to release at 1 psi if you wanted by removing some of the tension on the spring thus letting the waste gate open much earlier
i have to disagree with you about the boost controller,,,it works on a check ball and spring you could set it to release at 1 psi if you wanted by removing some of the tension on the spring thus letting the waste gate open much earlier
-Ted
03-07-02, 03:35 PM
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Originally posted by Josepi
How would you limit boost on a near stock setup with full exhaust. Could you do it via the intake?
How would you limit boost on a near stock setup with full exhaust. Could you do it via the intake?
1) Run a very small air filter cone, if you're running a cone filter.  I used to run a dinky cone filter (K&N part number RU-3120) that kept my boost down to 10psi with a full 3" exhaust; after throwing on an R.S. Akimoto rip-off FunnelRamII, my boost went up to 12psi.
2) I knew a guy who blew his 130k motor after installing the RB full 3" exhaust.  He rebuilt his motor and installed a 2" restrictor plate in the exhaust pipe between the downpipe and the pre-silencer.  He got consistent 10psi of boost afterwards.
-Ted
03-07-02, 03:46 PM
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If you want to keep the boost down, don't put the 3" exhaust on.
as for the boost controller, if it can raise boost,it can lower it (back to where you'd be without the controller)
sorry... play on words.
With a boost controller on a stock TII, how high can you turn it up? I've got one on my near stock TII and I closed it all the way. I see boost earlier on, even the top end of first, but I still don't see any higher boost. It seems to just control the speed my turbo spools up.
as for the boost controller, if it can raise boost,it can lower it (back to where you'd be without the controller)
sorry... play on words.
With a boost controller on a stock TII, how high can you turn it up? I've got one on my near stock TII and I closed it all the way. I see boost earlier on, even the top end of first, but I still don't see any higher boost. It seems to just control the speed my turbo spools up.
03-07-02, 03:51 PM
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Re: Would this be possible? (Keeping boost down idea)
Originally posted by Josepi
Could it be possible by using a smaller piece of pipe in the TID or using a 90 degree bend or two, to keep the boost levels down?
Could it be possible by using a smaller piece of pipe in the TID or using a 90 degree bend or two, to keep the boost levels down?
03-07-02, 04:50 PM
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Originally posted by RETed
You have no clue how a turbocharger wastegate system works or how that boost controller works.  You need to do your homework before you start claiming things that are utterly false; it just makes you look really stupid.
-Ted
You have no clue how a turbocharger wastegate system works or how that boost controller works.  You need to do your homework before you start claiming things that are utterly false; it just makes you look really stupid.
-Ted
03-07-02, 06:00 PM
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Originally posted by LLADNAR
explain it then,,this is how it works on my friends awd turbo talon,,is there something about the rx7 that is special
explain it then,,this is how it works on my friends awd turbo talon,,is there something about the rx7 that is special
Boost pressure from the outlet of the turbo is applied to a diaphragm in the wastegate actuator. When this pressure overcomes the force of the spring behind this diaphragm, the actuator opens the wastegate, bypassing exhaust gases around the turbine instead of through it, thereby maintaining a constant compressor wheel speed and hence constant boost.
If you lower the pressure signal sent to the wastegate actuator, the actuator will open the wastegate later, resulting in higher boost. A boost controller does this by bleeding some of the pressure out of the wastegate actuator line. The same thing can also be achieved with an inline pressure reducing valve.
The only way to reduce the boost level would be to increase the pressure in the wastegate actuator line causing the wastegate to open earlier. Where are you going to get more pressure than the turbo is producing?
There is nothing special about the RX-7's turbo. I just think you may have misunderstood whatever your mate did to his Talon.
03-07-02, 07:25 PM
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Originally posted by LLADNAR
explain it then,,this is how it works on my friends awd turbo talon,,is there something about the rx7 that is special
explain it then,,this is how it works on my friends awd turbo talon,,is there something about the rx7 that is special
-Ted
03-07-02, 09:32 PM
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as I stand, I'm hitting about 9 psi with the RB exhaust and stock intake box and stock TID. I hit 11 with a k&N cone and stock TID.
I think this summer I'm going to add a 3" cat which I'm hoping will lower it a few psi. Then I can add a bigger TID and cone filter and still only creep to 10. (hopefully) I figure I'd have more power and better spool with a cat, k&N, and tid then with no cat and stock intake. but the boost creep would be about the same. plus with the cat I'd be legal
we'll see what happens, the best way would be to take the turbo off and port it though... but that takes more work
I think this summer I'm going to add a 3" cat which I'm hoping will lower it a few psi. Then I can add a bigger TID and cone filter and still only creep to 10. (hopefully) I figure I'd have more power and better spool with a cat, k&N, and tid then with no cat and stock intake. but the boost creep would be about the same. plus with the cat I'd be legal
we'll see what happens, the best way would be to take the turbo off and port it though... but that takes more work
Last edited by Scott 89t2; 03-07-02 at 09:35 PM.