Year of 604 Crate

[Tlangley]

How can you tell what year the crate was built. What year did the change the heads on the 604 crate? How many laps do you run before it is a good idea to change the valve springs? What are the best headers to put on the 604? I am just getting into the crate class and am looking at a used one but I would like to know what exactly am looking at. I ahve always built my own engines and always knew what I had. Thank you for your time.

[jason29a]

You can tell the year of the engine by looking on the block... Just below the head, where the water pump bolts up. There will be a stamped number. You would want an 08 or newer.

Example... 0P04 = 2010
9P04 = 2009
8P04 = 2008

[ptodd]

u should change you spring,locks,retainers every 8 races. the best header is the beyea . it tough to buy used engines you dont know what you are getting. stay away from any engine that has rm bolts we have had 2 brought in in the last couple weeks and have been cheated to the point of it requires a new engine. with newer heads you want a 08 or newer

[DK1]

How come some ppl say you change your springs every 300 laps and others are saying every 8 races?

[ptodd]

depends how many laps you put on it in a night. the track around here in 8 nights you will have 250 laps on it thats not counting any extra lap races.