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Power Strokes
7.3 Aftermarket
Options for Compounds with a 38R
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[QUOTE="TARM, post: 351508, member: 578"] Looking at the 4718 I seem to recall Charles having issues with drive pressure once total boost climbed to around 70 psi. Now granted he made 650 so that already would meet these goals. But that got me thinking. The 4718 has a very good comp map as a medium sized amtosphere charger but the turbine wheel is backing things up. What about going with the gt5518 which is basically the 4718 comp map (same wheel size'trim, and comp a/r with the 55s 111mm high flow turbine wheel. You can use the vband housings up to 1.40a/r 80% effiency vs 69% of the gt47 and about 20lb more air/min on the hot turbine side. With the larger turbine of the 5518 I would think you could stay with a 1.0 housing on the 38r and gethe slightly faster spool up. Looking at the maps without the drive issues with the larger turbine you could max the system out with 120lb/min with PRs of up to 3:1 on either turbo for up to 120psi. But the sweet spot looks like 55-80psi and 80-100lb/min with PRs from 2-2.5:1 each charger. Plenty far from either edge of the mapand the center efficiency islands. As I do not have any hands on experince with compounds does this make sense or am I way off. To me it looks like a great mid sized street/tow/do all combo. [/QUOTE]
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Options for Compounds with a 38R
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