Hi all, I have the 1.9 turbo upgraded, now 8.4:1 cr, chromoly pushrods and racing springs, all other parts stock, adding cranktrigger system and methanol injector before carb running a Spitronics Management system to control ign and Meth injection to minimize detonation and cooler eng temp,
I used to boost 1.3bar boost at 7.3:1 cr, would I still be able to boost 1bar with new cr of 8.4:1 and 6500rpm?
Highest acceptable boost on a 1.9wbx
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Re: Highest acceptable boost on a 1.9wbx
Methanol injection should be enough but controlling ignition is most important. but 8.4 isnt really that high of a compression ratio. Without intercooling i would not venture that high for long .
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Re: Highest acceptable boost on a 1.9wbx
also depends on what fuel you will use.
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Re: Highest acceptable boost on a 1.9wbx
I thought the test was if the rods try to get out?
If you don't knock/detonate you can get away with ~anything.
If you do knock it will die quickly at 5 PSI.

If you don't knock/detonate you can get away with ~anything.
If you do knock it will die quickly at 5 PSI.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Re: Highest acceptable boost on a 1.9wbx
Running 95 Octane with the Methanol, also have charge cooling installed and timing will be controlled by Management system, how bout now?
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Re: Highest acceptable boost on a 1.9wbx
Running the stock 1.9dg on English 98ron you can just about run 18psi, but with a bigger cam and meth injection I would say around 24psi