So today I was driving my car, and accelerating away from a stop light in 1st. As soon as I hit like 4800 rpms, the car lurched really hard and I could hear the tires squeal. I immediately put my foot on the clutch and shifted to 2nd. It seemed to drive fine, so I go up the road a ways and try it again in 1st. As soon as it hits right around 4800, same thing. It feels almost exactly like as if I was in third and was going to shift to 4th, but accidentally hit 2nd. I was like what the hell, and drove it normally to my destination. It drives fine otherwise, but now I notice a strange problem with the tach. If I give it some gas to get the rpms to like 5200, then let up, the tach goes all the way to zero for a split second then shoots back up to about 4600 as it comes back down. This seems like some kind of vacuum problem, but Im not sure.