BMF heads?

[565bbc]

I was just wondering if anybody on here has anything good or bad to say about bmf heads on a bbc. I seen quiet a few post from people on another site that had bad experiences with there heads and kind of made me worry a little bit since I got the 385's on my engine.

[Hitchcock]

I dont know anything about the BMF heads. But if you ask around enough, somebody has had a bad experience with every aftermarket part made. Just my 2 cents. Good luck.

[572 BBC]

x2

[DOTracer]

The best thing you can do to help the weakness of the BMF 385/405 is to run the T&D shaft rocker system with the 1 piece intake stand. This distributes the load over the whole head.

[565bbc]

The best thing you can do to help the weakness of the BMF 385/405 is to run the T&D shaft rocker system with the 1 piece intake stand. This distributes the load over the whole head.

I appreciate that!

[Jeff Chandler]

The best thing you can do to help the weakness of the BMF 385/405 is to run the T&D shaft rocker system with the 1 piece intake stand. This distributes the load over the whole head.

I 2nd what Todd says. I had 45+ passes on my 525 shifting between 91-9300 and a trap RPM between 92-9350 RPM without any failures. Spring replacement was needed for weak springs, never broke one. Engine made 1140hp

[565bbc]

The best thing you can do to help the weakness of the BMF 385/405 is to run the T&D shaft rocker system with the 1 piece intake stand. This distributes the load over the whole head.

I 2nd what Todd says. I had 45+ passes on my 525 shifting between 91-9300 and a trap RPM between 92-9350 RPM without any failures. Spring replacement was needed for week springs, never broke one. Engine made 1140hp

Wow that's some serious rpm's! So from you guys experience do you think it's just a not so good casting or is it a combo of spring pressure and rpm's? I only shift mine at 6900 and peaks out at 940 hp.

[wikd69]

I 2nd what Todd says. I had 45+ passes on my 525 shifting between 91-9300 and a trap RPM between 92-9350 RPM without any failures. Spring replacement was needed for week springs, never broke one. Engine made 1140hp

Trapping at 9,350 RPM ? Really ? Truly ? Holy smokes !!!!!! That big block at 9350 rpm must sing like a mountain troll on steroids, sheesh !!! Man I'd love to see that bad boy run

[DOTracer]

The BMF heads used a Canfield casting done just for CFE to put their CNC programs in. I had the 310 BMF's and had no casting issues, but the intake port as much smaller than the 385/405. From what I've seen the larger models had the port height to where they only had maybe 3 threads for the intake stands which was the weak point on like two cylinders per head. Just not enough meat for the threads and the stresses the rocker stands see with high spring pressures & rpm.

I was told by CFE the used the same casting for all the different port volume programs at the time. The smaller ones were stronger as they had more meat in the roof of the port.

Now, some of the new pictures popping up with the heads cracked on the exterior through the chamber, etc??? Not a clue what's the deal there.

[Jeff Chandler]

On the other 2 525's in the class they had nearly 100lbs more seat pressure than I did(440@2.200 to 350@2.100)maybe that helped reduce the chance of failure but I
m pretty sure those other 2 had no valvetrain related failures either and they came from the shop so other than my spring pkg I'm pretty sure the parts where the same.

[565bbc]

Well just to be on the safe side I'm definatly going to look into getting the T&D shaft rocker system before I start racing again. I'd hate to even think what it would cost me if one did break! LOL! Thanks for all your help and replies guys.

[FARRIGNO]

i have the bmf 350,s on my car for the last 2 yrs,and not one problem! a also bought my heads back in 2006, and they dont look anything like the canfield castings [casting plugs at end of each head],fwiw.

[388fdragster]

I have a set of the BMF 405 heads that came on my APD 555 Engine that I bought new. I have ran my dragster for 2 years and this fall 2009 one of them cracked and the other blew apart from the inside of the head above the exhaust valve and it blew the whole valve spring in a perfect circle inside the head bolts all the way around the spring and rocker. I have pictures to show you if you would like to see them. I was wondering if anyone else has had this problem. Every year i fresh up my motor from carburator to oil pan.

[Hitchcock]

I have a set of the BMF 405 heads that came on my APD 555 Engine that I bought new. I have ran my dragster for 2 years and this fall 2009 one of them cracked and the other blew apart from the inside of the head above the exhaust valve and it blew the whole valve spring in a perfect circle inside the head bolts all the way around the spring and rocker. I have pictures to show you if you would like to see them. I was wondering if anyone else has had this problem. Every year i fresh up my motor from carburator to oil pan.

I would like to see the pictures if you dont mind.

[388fdragster]

here is a picture you can look at. This is the first i have ever seen a head do this.