wastegate question

[TKGN1]

Swapped turbos (ta62 to pt 54) and now can't get boost to go down below 20 psi. Using deltagate, with same boost control as before and not changing anything else. Question is, would the pt54 move more cfm's thus overwhelming the capacity of deltagate? Possibly need to step up to racegate or add another wastegate to increase flow? Or any other ideas?

[trading t/a]

have you tried taking tension off the spring? Whay method are you regulating boost(bleeder valve or adj. on deltagate). Try running the line from the turbo directly to the deltagate. it should give you what the spring is rated for.

[TKGN1]

Zero tension on the spring, bleeder valve, line is ran direct . Don't think it's the set up because it worked before the swap, just curios if wastegate could be undersized. Thanks for the help though.

[turbo buicks]

i was reading on the TiAL website and it said if you run more boost a bigger WG isnt needed but the lower the boost you run the bigger is needed. this is b/c makin 25 psi you use a lot of the exhaust gas to spin the turbine and keep it spooled. makin 7 psi there is a lot of exhaust you dont need going thru the turbine b/c 7 psi isnt hard to make so now you need to flow a ton of exhaust thru the WG to control 7 psi whereas with 25 psi most exhaust could bypass the gate and go to power the turbine. seems like a valid theory IMO since i heard of many guys running 70 series turbos with stock wastegates.

[trading t/a]

that being the case(line ran direct) I would look at the puck it seems to be the only logical explanation, other than fuel of course.