i have an 87 iroc i just picked up. It imediatley shifts in to second if i bake the tires on its own even if i hold it in first manually. I cant get a good launch. My other iroc will hold way first longer. Im wondering if it has a problem. .

 

I have seen transmissions shift on their own due to the internal valving that will not let the line pressure get too high without shifting. This is to protect the engine and the trans and is setup that way from the factory. Some transmissions are different from year to year and they all respond a little differently.

 

check the tv cable adjustment. some 700-r4's will automatically force the 1-2 shift,even in man low