long story short bumped into a old work mate this morn and he running a calibra turbo lump in his 306 and i asked him how it was running and the answer was "oh it well over 500 bhp now" now correct me if i wrong but he on a gt28 turbo and is that not poss as he claims 500 ponys from these engines is easily attainable

 

i always thought a gt28 would be good for 300 max whereas a gt28R or RS an out 350?

Depends which 28 hes running i suppose, GT2871R for 370+ but im not really genned up on turbos or vauxhall engines, Chips your best man for this one

 

bttt

 

500bhp out of a c20let is possible but it takes loads of work and lots of money to get it there
my mates got a mint green corsa thats 431bhp and hes spent loads on it to get it there

 

Supports up to 350 hp. T25 style housing - a perfect high power T25 or T28 upgrade turbo. Dual ball bearings allow for higher efficiency and much faster spool up. Compressor: 60 mm, 60 Trim, 0.60 A/R. Turbine: 62 Trim, 0.64 A/R. Internally wastgated, oil cooled.