So anyone that has been around me long enough should be familiar with my process. I basically spitball ideas to make a bunch of horsepower (i.e. all aluminum big block) and then go a different direction entirely. I pretty much decided against the aluminum block for a few reasons. I worry a lot about the weight of the rotating assembly pulling on the main caps once it gets heated up. There is going to be some stretch/expansion and with time I think it could cause the main clearances to open up.

My new project idea is to basically build the first motor I had which was a 468ci, 10:1, GM Iron O-Port Heads, Comp Cams 294S Solid Flat Tappet, Holley Strip Dominator Intake and 850 Double Pumper with my 4 speed went 12.1 @ 118MPH. I am going to build an identical version of that with a twist. The O-Port heads I have are #215s with bigger valves and very little porting that I can tell (mostly just casting flashing cleaned up from the looks of it). I am going to put them on there as is and run it at the track, then every year I want to pull them off and port them some and take it back to the track to see if any improvements have been made. I would like to get it into the 11s but my main concern is the MPH I want to beat the 118mph that I had with my old motor. It likely won't work out like I plan and will likely be slower than I have visioned but I think it will be a fun project that I can learn from.

Any opinions, ideas or comments?

 

Vortecpro is getting oval port big blocks into the tens with some port work and the larger valves. He has video series on youtube showing the work needed. Might be a good place to start.

 

Nothings gonna happen with an aluminum block

Port the heads now then hit your 120+. As you probably know removing flash doesnt really do anything. in the right hands those ovals can make some power,,compression really helps when running a healthy cam. Its more than a percentage number

 

Not sure what you had for cam, or if you dynoed the combo, but 12.1 @ 118 should be easy to improve on with your 468 inches, depending on your gearing, transmission and tires.

 

76strokervette:
Thanks for the heads up I'll have to check the videos out.

cuisinartvette:
Port the heads now then hit your 120+. As you probably know removing flash doesnt really do anything. in the right hands those ovals can make some power,,compression really helps when running a healthy cam. Its more than a percentage number[/QUOTE]

I don't know if you can say "nothing will happen" with an aluminum block. With street use I think the heat, weight of the rotating assembly and RPM will eventually loosen things up. Aluminum rods when subjected to heat expand so it stands to reason that the potential is there for the threaded mains to be a problem area. Just a possibility that I don't want keeping me up at night. I also so a couple pictures of main studs being pulled from the block that deterred me.

I know removing the casting flashing doesn't do much (I didn't do it), that was kind of my hopes. I would like to get a good baseline on the heads with the minimal work....and then progress from there. I think it will be a fun experiment that I can learn from. I'm going to build it like my first motor so the "control" for the experiment is there. The only difference is going to be the heads and tuning.

JoeMinnesota:
Never did any dyno time, I think the engine still had a good bit left in it . The cam was a Comp Cams 294S Solid 248 @.050" and .595"/595" lift on a 110LSA. I will likely be using that cam this time around again. I currently have 4.11 gears & 4 Speed but may be switching back to 3.36s for practicality purposes and the fact that they made no difference in my track times, traction wasn't really ever much of an issue except on the 1-2 shift occasionally (even with 215/70/15 BF Goodrich Radials), I do still have some 28x11.5x15 MT ET Streets if it becomes a problem but I doubt I will need them.