H1 Alpha top speed

[ssgharkness020147]

Plenty of people have done this change. I know of two H1 owners making over 600 hp in their duramax rigs. Lots of people that do those mods buy them through the dealer and dont post online. The parts dept at my local dealer is about to put a stage III computer in one of his customer's Alpha's.

Originally Posted by Huck BB62

I understand, the Dmax is an expensive critter. I'm still surprised that noone's chipped and did the aftermarket exhaust thing on their H1. Tons and TONS of people are doing it to the trucks. But again, being a Dmax owner, I completely believe that it's fine stock, so I never bothered. Personally, I believe that the H1 could do about 120 with the program change.