Hey matt.

The head guy I used is Mike Haley, at Hi-Flow heads in Alsip, IL. Mike is a super guy. He does heads, and thats it, since early 90s. Extremely anal, honest, and pretty good timeframe. He answers the phone, and always willing to discuss your needs, etc.

When I first brought him my old dart heads, he inspected them thoroughly. He had me come to the shop, to actually show me what was done incorrectly to them, and what would need to be done to correct them. Many shops will tell you this or that, and expect you to take your word on it, but Mike actually shows you.

I mentioned these EQ castings to him. At first he seemed skeptical. When I mentioned that they were supposed to be the same castings as the RHS/Pro Topline, he seemed more curious about them, as he had worked with those in the past. Anyhow , i orded two sets of them, and brought them to mike. He immediately began looking them over, and liked what he saw with them.

We started doing flow tests. We flowed the darts I had, and had a baseline. Mike started doing some mods to the EQ heads. He adjusted the throat diameter, ported the chambers, did a nice valve job, etc. The exhaust flow was a little weak he felt, so he did a little cleanup there, and the exhaust improved.

Overall, right out of the box, they outflowed my old darts. I could have stopped there, and been fine. The goal was to get the flow numbers from .100 to .650ish up. The port was flowing pretty good at 600-700 out of the box. The low lift flow was what we were looking for.

As for setup, mike checked each and every valvespring for pressure and coil bind . Each valve gets micd for install height check. Unlike the last shop that did my heads, and had major variance in install heights, spring pressures all over the place, wrong hardware with springs, etc. You will not get that kind of work from Mike at Hi-flow.

I was not too concerned over the iron head thing with a supercharger. Mercury marine did it for years, and many many have supercharged stock mercury engines, with iron heads, and had zero issues. I do like the fact, iron is more resistant to corrosion, expands at the same rate as the block, and head gasket brinelling is really not an issue. Everyone has their own opinion on that topic though. As far as the weigh gain, that obviously didnt hurt me. Matter of fact, maybe it helped. My boat likes bow lift, maybe the extra weight in the stern is helping . Who knows

It's so easy to measure one intake and exhaust and then set the rest up the same.. And that's where you get into trouble.

For example; I was adjusting installed height on a set of heads for a customer this summer and out of 16 one was way out... After scratching my head for a moment and thinking the machine work to the spring cups were machined incorrect, I pulled the intake valve out and measured it up against the rest of the intake valves and figured out that the one valve was shorter then the rest. I put a new valve in it so they were all the same but if it went unchecked it could have surely meant disaster for this high dollar engine!

Panther, how did you end up making out on those 502 MPI you did with the EQ heads? A buddy was thinking about them for his 502 mags

The combo I built netted him roughly a 10mph +/- gain. He put a lot of hours on them this year and was really happy with everything.

Fly by: https://youtu.be/r2QiV9bHmU4

Idle: https://youtu.be/bzhqoP7eIAc

Awesome. Not just on the heads, but the whole builds.

Thank you

Hey guys I'm thinking about using ch454a heads on an 502 Mag I'm freshening up. Could anyone comment on the exhaust valve length there using, spec sheet recommends a +.100 valve. Thanks

Ferrea 1261P super alloy is what i am using


http://ferrea.carshopinc.com/product...63828/F1261P-8

Mild Thunder did you use std length for the intake also.

Those are +.100 exhaust valves. I forget which # i used for intake, but they are +.250 if i recall.