Is there a formula to determine the size of the wastegate? If I have a large turbo, but want to run low boost for awhile, I know that I will need a big wastegate, but how big?
this depends also on a/r of the hot side, but I have a "thumper" frame turbo and I use the racegate. They are sized for horsepower. This one will control up to 900 or so. I have limited my boost down as low as 3 psi and had no boost creep, but you have to keep in mind the way it's mounted in the system will have a direct effect on its capabilities. I mounted mine tangentially right from the turbine housing (I drilled a 1.75" hole in it with a hole saw). You can eassily weld stainless to cast iron (due to the high nickell content) just use 308 filler rod, preheat the cast and it's as easiy as pie.
As the turbo is now, the A/R on the hot side is probably to tight for a 383. It will probably spool-up pretty fast though. Therefore I believe that I won't have as much air to "gate" as I would with a larger A/R. I looked at the TIAL wastegates and they seem resonable. Will a 38mm due the trick? I only want to run "low" boost until I get my fuel management under control. Right now, I don't even know what I am going to use for an FMU. I may as well throw this out while am at it. I will also need a BOV and it will need to be properly sized as well, so I'm sure the questions will just keep on coming. I haven't gotten my copy of Maximum Boost, yet. Probably because I live out in the sticks. Hopefully that book will help clear up some questions for me as well. How did you wait while you built your ride? This is getting hard!!!!
PAtience my friend, patience. I built mine in the middle of summer, it was quite hard, but I knew I had alot to look forward to. But to be honest, the construction is the part I like.
Corvette Store
Wastegate sizing?
