Internal or External wastegate

[Speedfreak]

Because with a larger turbo, its harder for a smaller wastegate to bleed off enough air to keep the boost down. I have a scm61 on a Turbonetics manifold, and a Tial 40mm. I can't keep it from creeping on pump gas. I've ported the manifold as much as possible to get as much air to the wastegate, but with no avail. The placement of the wastegate on this particular manifold isn't the greatest, but in any case, the larger the turbo, the larger the wastegate needed to hold low boost levels.