This Seirra has 47,000 original miles. It has a 305 with a 700r4 transmission. It was all original until I did the following modifications, replaced the manifold with an [COLOR=blue! important][COLOR=blue! important]Edelbrock[/COLOR][/COLOR] Peformer, installed 60,000 volt distributor, installed headers.

Since these modifications my transmission slips while shifting into 2 & 3rd when excellerating to fast, after shifting it works fine and doesn't slip. It will shift fine if I let up on the [COLOR=blue! important][COLOR=blue! important]gas[/COLOR][/COLOR] as I reach the shift point.

Could any of my modifications cause the problem or is the [COLOR=blue! important][COLOR=blue! important]transmission[/COLOR][/COLOR] having problems