stroked small blocks in the race cars?

[blykins]

Originally Posted by MAStuart

My 1964 Mickey Thompson catalog lists stroker cranks for 289's.

Jim did your engine builder put the scare on you to upgrade? Depending on your tune you would be fine up into the lower 500 Hp range. Now if you were going 24 hour racing.....get a better block. I have an Jan 67 hotrod artical on the gurney eagle engines. Dan said that they had made as much as 448Hp with 271 HP cast iron heads on a 325 inch engine. So they were making them big before 67! Also the big numbers were 506 HP from a 289 with the gurney eagle heads on gas with webers. So they were making big number way back before 67.

How did your engine look wheen they took it apart? Any problems? There is a guy out east that has a progam to cnc port 289 heads that guys have been making in the 425 to 450 range with. I think they are also remaking the C6FE heads and cnc porting them. There is nothing like a real 289 making big power. I really like them when they use a factory 289 block ,heads and crank. Yes with aftermarket blocks and heads and cranks they might make a little more power. But I dont think they are as cool.

If you can find a nice factory block, they would last at those levels all day long. Older blocks were much more stable/stout than the newer 302/5.0 blocks.

I put bronze lifter bore bushings in to put them to factory spec and also install billet main caps. I personally would have no issue running them up to .060" overbore. I also use a lot longer rod than what guys typically run, which requires a custom piston and rod setup.

RPM used to make steel 289 cranks but RPM quit making a lot of crankshafts last year because they didn't know what the tariffs would do.

A well ported 289 head will flow about 200-220 cfm, depending on the casting, while keeping the port volume in check. We convert them to 7mm or 5/16" valve stem size. That supports 450 hp easily.

[MAStuart]

RPM's site still has them listed but trying to get one might be a different story. I am not sure what Mike gets to run his cnc program on a set of 65 289 heads . I have read that they were in the 230 CFM range with plenty of port wall left. He also stated that the race ported C6FE heads were good for another 20 HP over the 289 heads . Now if the price of the C6FE heads as posted in one of the above post is true I am not so sure that if a very good value other that bragging rights about how much your heads cost. But then again I dont have deep pockets. I have holes in mine!

[blykins]

Originally Posted by MAStuart

RPM's site still has them listed but trying to get one might be a different story. I am not sure what Mike gets to run his cnc program on a set of 65 289 heads . I have read that they were in the 230 CFM range with plenty of port wall left. He also stated that the race ported C6FE heads were good for another 20 HP over the 289 heads . Now if the price of the C6FE heads as posted in one of the above post is true I am not so sure that if a very good value other that bragging rights about how much your heads cost. But then again I dont have deep pockets. I have holes in mine!

I wouldn't be concerned about the port wall thickness, I'd be concerned about the port volume. A hogged out port, even if it flows a lot, would make for a slugglish 289 on the street. On the race course, it would take a bit of rpm to make it efficient.

[PDUB]

Originally Posted by blykins

A well ported 289 head will flow about 200-220 cfm, depending on the casting, while keeping the port volume in check. We convert them to 7mm or 5/16" valve stem size. That supports 450 hp easily.

Originally Posted by blykins

I wouldn't be concerned about the port wall thickness, I'd be concerned about the port volume. A hogged out port, even if it flows a lot, would make for a slugglish 289 on the street. On the race course, it would take a bit of rpm to make it efficient.

Do you send those heads out or do the porting in house, Brent? Are we talking about the same porting in both of your quotes above? In other words, if you port for the top quote, do you end up with the bottom quote, or can you have good street performance with the top quote? Reading between the lines, I think the latter good street performance, but just checking.