FINALLY here, TIAL 60MM wastegate

[GNVYUS 1]

I guess the 60mm might be needed IF we wanted to run 5 or 6psi but that spring would be all jacked up if the rest of the run was done around 35psi, it would creep open too soon and be a touch lazy up top. And going fast generally means you are running high psi, so you are using more exhaust gas in the turbo housing and require less of it to be exhausted through the wastegate.

I am curious as what Don might need the 60mm for, I believe he has a stroked 109 but 250 cubes is jack for a 60mm.

 

[Alky V6]

I'm running a 224 cube TA block with a 3.06 stroke Moldex. The idea of using the 60mm was to get as quick a map rise as possible and have enough wastegate capacity at the peak of the map rise so that map didn't overshoot the target boost. It actually works very well. I wish there was some way to post one of my datalogs. The map rise is unbelievably steep with less than 1 psi of over shoot of the target which is 31 psi. Some of the reason for no overshoot could be the fact that the T76 I'm using has a very hard time putting out more than 31 psi boost with my combination, by any means.

One nice feature of the 60mm is the ability to control the ramp up speed of the boost by adjusting the spring package and tension adjustment. I started my tuning with a very light spring package in the wastegate. As I worked my tuneup higher, I would turn the adjuster in until it bottomed and switch to the next stiffer spring package and so on and so on, until I ended up with the stiffest spring package and the adjuster in about 1/4 travel. All the while noticing how the boost ramp up speed increased. The wastegate creep was kind of a nice thing to have. It controlled the boost ramp up speed. Nice tuning tool to have for tracks that might not be biting well. I tried turning the adjuster in farther than the 1/4 travel and boost rise was starting to actually feel too quick, so I backed it down. The 60mm wastegate is by no means cramping my style.

This is how fast the boost is rising for me. Keep in mind, I do use nitrous to assist. First off, I'm using a 2440 rpm, at 0 boost, stall torque converter. I stage while preloading the T/C at 2300 rpm. The boost is zero at this point. On a 3 amber tree, I go WOT at the first sign of the 2nd amber. This is when the nitrous is activated. On the 3rd amber, .5 seconds later, I release the transbrake. At that point, the rpm has reached 4300 and the boost is around 16 psi. If there's any valve creep of the wastegate going on at this point, I'm dang greatful. I wouldn't want the boost rising any quicker.