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my name says Guest, but Im really a MEMBER
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Discussion Starter #1
whats the max boost you can push a IHI RHB5 turbo too, with the wastegate tube disconnected (which would give you max boost right?)
 

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Classic Man
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usually you cant get more than 15ish psi out of an internal wastegate unless you do something to make it harder for the flap to open, like a spring or welding it shut.
 

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Discussion Starter #3
ok, thanks. thats still a little much for a stock block.

Goal:
put in a built block and max out turbo.
Then if all goes well and I can get it tuned correctly put in a bigger turbo.
 

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I think you could possibly max that turbo out and still be fine on a stock block as far as the "safety in numbers" goes. The turbo will stop making power up top regardless around 5-6k. It's a blast on the low end.
 

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Discussion Starter #8
this turbo stops making power at 5-6k why?. as in the boost starts to drop off or the efficiency decreases substantially?
 

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they will boost spike high but fall off to about 13-18 pounds depending on how high the engine is revved. ive had a lot of experience with this turbo form my mx6 turbo
 

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with the wastegate disconnected, it could possible go even higher. but it would just be extremely hot compressed air. with a boost controller i got mine to hold about 18psi to 6 grand. they are very small
 

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Discussion Starter #14
there small, but I didn't see anything in maximum boost that says that a smaller turbo at 5psi is any different then a bigger turbo at 5psi as far as cfm. 5 pounds per square inch is 5lbs per square inch. they only thing it says is efficiency and heat generated by lower efficiency.

nevermind that was irrelevant. to your statement. yeah, I could see how a smaller turbo would not be able to produce enought cfm to reach boost levels and or at higher rpms.
 

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my name says Guest, but Im really a MEMBER
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Discussion Starter #18
no they wouldn't if they understood efficiency. which I get. I don't get this a bigger turbo has more cfm per lbs of boost.

If someone said, how a bigger turbo might be more efficiency and run cooler which would cause the air to be more denser, which would increase the amount of air going into the motor.

ok, so it flows more air. then it would take a shorter time to reach 5psi.and be able to maintain that psi easier. which would increase efficiency.
 

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you'll get it
just think about it more
bigger pipe can flow a greater amount of substance (gas,fluid...etc)
but it takes more work to flow more
mostly its the design of the turbine blades that optimizes the ratio of input to output
but the physical housing size will dominate the flow rate
 

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Classic Man
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a larger more efficient compressor flows denser air. so more air enters the cylinder.

think about this guest.

is a turbo pumping the same amount of air at 5psi and 4500rpm as it would be at 5psi and 7400rpm? (presuming efficiency would be the same)
 
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