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I am reverting back to this thread since we are not restoring this car for another year or so.
I took it out for a drive and a little testing tonight. I wanted to see where it boosted at and what the vacuum readings were on it. I pulled the boost gauge and installed an accurate vacuum and pressure gauge. at idle it has a 20 inch vacuum. I did not think it would be that high. When cruising steady at 55 MPH on flat ground it was at 17 inch vacuum. I done two full pulls and both times it went to 8.5 PSI. I assumed that my gauge was off the first time so I did it again and it went to the same place. I got home and tested my vacuum and pressure gauge and is on the nose correct. I then tested my fluid tank cap because I thought it would pop before that but it pops at 9 psi.
I then tested my boost gauge and it is at 20 inch vacuum and 8 psi at each extreme of the needle.
I am fore sure surprised that it boosts this high. I feel sure that this turbo has never been apart or modified. I did this with our automatic car and can’t remember what the figures were. I am going to do that car soon but it does not have the original cam in it so the vacuum readings will likely be different.