herecomesboost build thread (part 2)
Thread Starter
Joined: Mar 2005
Posts: 4,692
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From: Centreville, Va
How many lbs your wastegate spring? You may need a stiffer wastegate spring to hold to redline.
Currently I am experimenting with the 4port Mac solenoid boosting to 25psi. Goals is to hold 25psi to redline. One difference I notice is boost comes on faster resulting in more torque. The duty cycle on the 4port is very sensitive. A small change in the duty cycle can result in a huge boost oscillation to red line. It was critical to find the exact duty cycle for the boost level. Unfortunately, I got tired of doing runs by myself, so I had friend drive so I can optimize the duty cycle quicker. A 4th gear pull was too much for him to handle, the rear end spun sliding towards a telephone pole and we bounced back onto the road. Just a damaged bumper, a tail light, and a rim. Got everything replaced and just waiting to put on a new set of fresh tires and see if it still runs straight. Be safe. 25psi is too much to handle on crappy tires.
Currently I am experimenting with the 4port Mac solenoid boosting to 25psi. Goals is to hold 25psi to redline. One difference I notice is boost comes on faster resulting in more torque. The duty cycle on the 4port is very sensitive. A small change in the duty cycle can result in a huge boost oscillation to red line. It was critical to find the exact duty cycle for the boost level. Unfortunately, I got tired of doing runs by myself, so I had friend drive so I can optimize the duty cycle quicker. A 4th gear pull was too much for him to handle, the rear end spun sliding towards a telephone pole and we bounced back onto the road. Just a damaged bumper, a tail light, and a rim. Got everything replaced and just waiting to put on a new set of fresh tires and see if it still runs straight. Be safe. 25psi is too much to handle on crappy tires.
Thread Starter
Joined: Mar 2005
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From: Centreville, Va
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hey kyle looking good man !!!!! just chiming in on the fuel wicking.... your not worried ? Im thinking of a walbro 400 as well but am worried about the install, (not my ability but the fuel wicking) you thinking all is good ?
-Lee
-Lee
Thread Starter
Joined: Mar 2005
Posts: 4,692
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From: Centreville, Va
Hey Lee. Thanks dude! The likelihood of that happening (fuel wicking) is minute, in my opinion. My initial plan was to drill holes for two studs, but there simply isn't a good place for them (the bottom of the fuel hangar mount is not flat; no good place to mount a bolt/nut).
Thread Starter
Joined: Mar 2005
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From: Centreville, Va
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