i just installed a new wastegate and a manual boost controller. i got the boost about where i want it 13 pounds. but when it shifts it spikes to 16 or 17 pounds. and at high speeds it starts to creep up past 15. ive blown headgaskets before at 18 so is there a good way to control this?

 

What size spring is in the WG? Try opening up the manual boost controller all the way so the WG sees full pressure and see if it spikes still. Like if its an 8psi spring and still spikes to 9 or something. That'll at least narrow down the possible problems.

 

without the boost controller it didnt spike. it would still creep though

 

Well good, you separated the two problems lol. Whats the details on your setup? Engine, turbo, which turbo kit, WG size, etc. Also do you have a pic of where your WG is in your setup? Placement makes a big difference, believe it or not.
I've heard of spikes with manual boost controllers before, though...

 

where is your gate and boost controler referenced from?
what size line are you using to the controller and gate?


is top of gate vented? i know with a electronic you have to apply pressure to top and side of gate to help control boost creep