8 bolt water pump overheats :(
 

Does anyone have any output on the 8 bolt pumps this 67 GTO has run hot for 34 years and now even hotter with a new motor! Do ya scrap this for the 11 bolt pumps or can they be tweaked to cool better??

Welcome.

Go to the top thread in this forum. It's titled "chalk one up for the cast impeller". it's a long read, but the first few pages should give you some ideas.

George

Yes, what George said. That thread is a good read. But that applies to the 11 bolt design. Not certain the same applies for the 8 bolt.

Anyway, here is a page which shows the heart of the matter ::
closing the gap between the impeller & the divider plate ~ http://www.wallaceracing.com/water-pump-mods.php

Hope that helps your cooling issue.

Pulley size?
Shroud?
Fan?
Heating up at idle or running down the road?

I have had the same problem also on my 68 she just runs hot in the summer time .i dont drive it if it is above 85 out .however i am looking foward to tweeking my plates .

mine gets hotter than hell. 220 plus I just keep driving it. It didnt hurt it to run hot in 1968 and it wont now..
Actually, I am such a liar, the last few years I just dont drive my old cars in the summer daytime because they dont have AC. Im not concerned with the motor just my own comfort. (8-)

GRX, you are incorrect, those pictures on your link and the original post by George here on this board (page 1) were pictures of my 8 bolt pump!
Charles

Guess it was the 2nd and 3rd lines on that page which threw me off. ;)

> " This basically applies to the newer 11 bolt water pump. The older water pump is designed differently and may not apply. " <

Seriously though, the 8-bolt set up is nearly identical so should work. Which is what you were trying to say I believe. Thanks Old Goat.