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EMC 289

Posted: Wed Oct 09, 2019 3:32 am
by Mummert
Been home for a few days and finally starting to get back to normal. I've had a few people asking about some details about the engine and wanted to say thank you to some people that helped out with the engine.
The rules were pretty tight this year, so to say that there were tons of fancy parts would be a stretch. The bore was 4.041 filled by off the shelf JE SRP Pro flat top pistons. We played some games to get the ring tension down. Compression 10.47:1
The stroke was 2.88" a stock C3AE 260 crankshaft with a fair bit of shaping sanding and shot peening, ground 30/40.
The block was a 68' bored and honed with torque plates, a main girdle, align hone mains and decked .009".
Camshaft was an Isky hydraulic roller cam that we used Crower solid roller lifters on. 242* .595 / 242* .540 106* (I would make a few minor changes to it if I had to do it again) it was the only cam we ran and did work good.

The heads is where we spent a lot of time, Bill-C from Carlquist racing engines did his CNC porting and then we spent time playing with them from there. Its a great foundation for this engine, if your looking at working with OEM heads you should hit him up. We converted them to 8mm stems and modified Ls valves 1.91/1.53. Ferrea had the only 15 degree exhausts I could find. Everthing else was 25 degree and didn't seem like a good fit for the old shallow bowl exh port, not mention getting compression was already tough.

We battled a strange issue at the Competition with what appears to be an ignition issue (Jon Kaases advice) so we'll be testing the engine again in the upcoming weeks to see if we can replicate and solve it.

It was a nice week hanging out and meeting new people and talking with other engine builders. Thanks to JE Amsoil SAM Lonnie, Adger, RJ and everyone else that went in to putting on the show.

Gotta give to Blair Patrick, no one saw the old 390 coming.

To Carlquist racing engines, Dave Bloom,Jon Cloud, Todd Ferguson, John Hildebrand, Gary Camp (GRC) Steve Brule and my DAD THANK you,, these guys were a huge help making it happen.

Re: EMC 289

Posted: Wed Oct 09, 2019 4:31 am
by BobbyB
Congratulations!

Re: EMC 289

Posted: Wed Oct 09, 2019 6:34 am
by Carnut1
20170629_211650.jpg
So glad you are sharing with this build. I agree that Bill C 289 cnc is a great starting point. He bailed me out a while ago when I ruined a head for DV. This is a pic of the exhaust. I also agree that the exhaust on these heads work better with a smaller bowl so that flatter exhaust valve angle would be helpful. Thanks, Charlie

Re: EMC 289

Posted: Wed Oct 09, 2019 7:44 am
by bob460
Nice build and congrats!! =D>

Would make a nice engine in our XR GT FALCONS down under!

Interesting on the hydraulic roller cam with solid lifters...........how reliable would it be in a street car?

Would you add more exhaust duration if you made a cam change?......if so how much more?

Re: EMC 289

Posted: Wed Oct 09, 2019 7:58 am
by Carnut1
Bill C 289 cnc.jpg
Intake bowl of Bill C cnc work. From my old 289 thread. Bill C has these down.

Re: EMC 289

Posted: Wed Oct 09, 2019 9:52 am
by Steve.k
Very impressive engine Geoff thanks for update. Have one under bench for years wondering what to do with it.

Re: EMC 289

Posted: Wed Oct 09, 2019 10:08 am
by Tom Walker
Very impressive build and so close were 1 and 2. Congratulations to you and your team, well done.
Also, you make a very interesting point with this engine, something besides a "400" cubic inch can put up some fantastic numbers on the dyno.

Re: EMC 289

Posted: Wed Oct 09, 2019 10:16 am
by Walter R. Malik
Geoff, I am interested to know the difference in the power curve between the single plane intake manifold and the 2 plane intake .
I was told that you tried both.

Re: EMC 289

Posted: Wed Oct 09, 2019 12:20 pm
by Mummert
This is a bad pic but it shows or best score of 2513 at westech with weiand Xcellerator vs our best scoring run of 2520 at EMC with the Air Gap.
Pk hp Air Gap 446 xcellerator 451

Re: EMC 289

Posted: Wed Oct 09, 2019 12:26 pm
by Mummert
A quick snap of the weiand and good pic of run 34 at westech. This run is on the comparison above.

Re: EMC 289

Posted: Wed Oct 09, 2019 12:32 pm
by Mummert
As a point of reference to more familiar manifolds, We ran the Victor JR as well. It was up 4-5hp over the xcellerator, but we could not reach the 2500 score with it.

Re: EMC 289

Posted: Wed Oct 09, 2019 3:47 pm
by Steve.k
Geoff thats very interesting findings. I really like the airgap. I've done testing on 4v cleveland heads and from a torker to airgap we seen 18hp with airgap. On a 6k motor. Have not tried one yet on above 6k rpm.

Re: EMC 289

Posted: Wed Oct 09, 2019 3:50 pm
by Mummert
One other thing is that the Weiand manifold is ported to with in an inch of its life and is .025" thick is some places. I don't recommend people trying this at home. It was an expirement based off of something we saw on a highly modified torker about 15 years ago.
Not having played with these engines much in over a decade I was not familiar with some of the new intake manifold offerings from Trick Flow and AFR.
In hind sight I would have dropped a few degrees off the intake lobe and tested more single plane intakes.

Re: EMC 289

Posted: Wed Oct 09, 2019 4:00 pm
by Steve.k
We just got off dyno with 470 inch cast iron oval port chevy. The owner had a airgap the only thing we noticed on that engine was it liked a little more plenum. We added a 1" phenolic and picked up 11 on top. Even down low climbed about 3-4 hp.

Re: EMC 289

Posted: Wed Oct 09, 2019 4:18 pm
by PackardV8
Congrats on a great effort. I wasted some of the best years of my life trying to make power from those buzzing little anvils and never got close to your results.
Mummert wrote: Wed Oct 09, 2019 3:50 pmCamshaft was an Isky hydraulic roller cam that we used Crower solid roller lifters on. 242* .595 / 242* .540 106 . . . . In hind sight I would have dropped a few degrees off the intake lobe.
As to the cam timing, I just had a discussion with a similar build and he'd gone with 250/256. You chose eight degrees less on the intake and think still less might be better. Thoughts?