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rpalatine Mar 21, 2013 10:32 PM

too lean at high RPMs. Tried lots of things. Ideas?
 
Hi, My 2006 H2 with supercharger, headers, cam swap runs lean on the dyno at high rpms. We've tried Boost-A-Pump, new stock fuel pump (old one had 85k miles) but nothing. Any ideas? thanks!

rpalatine Mar 22, 2013 10:43 AM

update
 
just leaving a trail so folks coming after me know what happened when they find my skeleton at the end of the trail. The hypothesis now is that the problem seems to be caused by fuel delivery. The stock pump cannot keep up to the power level. So we're modifyng the fuel bucket to accept an Aeromotive 340 pump and with the addition of the boost a pump we're hoping it's good.

H2CANEPADESIGN Mar 22, 2013 11:20 AM

Mine is supercharged also. I have the Magnuson kit. There is a Secondary fuel pump that runs inline with the stock pump to increase fuel pressure. the kit came with bigger injectors and fuel rails. Summit racing sells walbro hi-pressure inline pumps. I believe that mine was a gsl391? When my stock pump failed @ roughly 100k I replaced both of them. the second time around I used a GSL392. The first one pumps roughly 190 liters per hour. the second was around 255 liters per hour so no fuel starvation issues and it helps keep internal engine temps down.

H2CANEPADESIGN Mar 22, 2013 11:22 AM

They do whine a bit when they get hot. try to mount it in an area that is not near anything that radiates heat or heat wrap the pump before you mount it if that is unavoidable. I mounted mine above the front cross member and wrapped it.

rpalatine Mar 24, 2013 03:40 PM

thanks
 
We'll see what happens


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