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FFR Master Builder
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Discussion Starter #1
i am running only 6lbs now from a powerdyne but was thinking of increasing the boost. i have 30lb injectors with a stock 5.0 so they should be able to handle the increase. how much of a increae can i go without hurting the engine. also is there a piont where boost can start to make gaskets fail and leak oil
 

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Going nowhere fast.
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Gasket failure isn't usually an issue until over 10 psi. On a stock enginem you are probably going to be limted by knock.You can run quite a bit more boost with water or water/methanol injection. Just remember, with a lot of boost, you can actually have an explosion if you suddenly get a very lean condition. Taking a hard corner with your gas tank less than 1/4 full or hitting the stock rev limiter (which I think is fuel-based, not spark-based) could suddenly lean you out.

If I would you. I'd slowly build to about 8 or 9 pounds, test driving with a good knock detector.

Mike
 

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John,
With your setup I would hold the boost to 9lbs. with the Powerdyne. I running the 9lb. pulley on my setup and am very pleased with the HP gain. The lean condition might be a problem, I am running the 30lb injectors to the max and will probably go to 42's next time around. You might also want to have a custom chip burned to retard your inginition about 3 degrees at the top end.
 

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So much of it is dependent on your combination and the tune that you are running. 9 lbs is commonly run on relatively stock motors but you must have a good fuel system and as Chuck said you will need to pull a couple of degrees of timing at full boost. I had nothing but trouble with my Kenne Bell at 9psi on my stock Mustang 5.0 with 30 lb injectors. Turns out it was beacuse the fuel pump wasn't quite up to the task. It would be fine under WOT but it would detonate when you jumped on the gas. Turns out the enrichment required (accellerator pump shot) when you lean into the gas just could not be supported by the 190 lph pump.

Water/methanol injection may be worth considering. http://www.snowperformance.net/
 
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