So, i'm looking to put a little performance in my truck and one thing i was looking at was either removing the cat or buying a high flow cat. I was looking into the pros and cons of each thinking i had a stock cat on there to begin with, but one day while going through the roll of papers telling what work the previous owners had done to the truck I found an old paper advertisement for a high flow cat with 'Installed' written on it. This has made me realize that i really don't know much about what's been done to my truck and where i want to go with it. I posted earlier to torque wrenche's sticky, but my truck is an '89 and he can't go before '90. The previous owners were a father and son, and the son (my friend's dad) is now in Japan and pretty much unreachable. So this whole story brings me to: how can i figure out whats already been done to my truck? I'm pretty new to working on my truck, but my goal is to eventually be able to do most all my own work. Any sort of resources on figuring this out would be a great help.

Thanks

 

on an 89 it would have 1 big convertor. If its a small one its probably been replaced

 

cool, thanks, i'm pretty sure it has been replaced, what i'm really looking for though is some way to compare what my truck would look like stock and what it looks like now. I don't want to upgrade/put a new mod in for something thats already been done to it.

 

Just find out what you want to change and look on the truck to see if it's a stock part or not. Thats the only way.