Anyone help me here? My 67 tbird may need a new engine and as i,m on a budget right now what is the cheapest block i can replace it with? Originally was the 429 but has been running a 351 since i purchased it 3 months ago. The current engine has d7te 8425s which tells me it was a 77 truck but what does the 8425s translate to? New to the cars and the country so any help would be great?And by the way the website is great!