Have a great running 470 now but could put a 512 together for just the cost of the stroker kit and machine work, I would just move all the parts from the 470 over and still have a good short block for back up. Do you guys think it's worth the extra 42 cubes? One thing I would change is CR ratio from 10.5 to 12.5 any idea on power increase I would see?

If you know the current HP per C.I. on the 470 use that formula and add .2 to .4 HP per C.I. for the increased compression and do the math I'm in the middle of preparing a proposal on a large C.I. B1 headed motor, I'm going to use 1.55 HP per C.I. on that estimate for pump gas with 10.5 to 1 with a single large CFM carb.on a cast B1 intake

I did the same change to my Lebaron. went from 3.900 stroke to 4.25 stroke, and another .005 on the bore. And of course the crank, rods, and pistons all new. I used the same World block, Indy SR heads, Indy intake and Racer Brown solid lifter camshaft. CR went from 13.5 to 1, to 14 to 1. Dome much smaller on the 512. Quickest pass with 469 c.i. engine was 5.53 at 123, and at 512 c.i. it went 5.45 at almost 126mph. I did try switching from a 1050 carb to an 1150 on the last race of this year and went 128 mph but slower. Only one pass then I switched back to the 1050, and was .09 quicker and 4 mph slower. Same 1.21 60ft. Something not right in the middle but did not have the time to tune, so I switched to the tried and proven 1050 so I could have a chance at winning some cash. I did get to 4 cars on sat. and a R/U on sunday in FB class at Holly Springs thanksgiving weekend.

I always vote for more cubes, but I would stay with 10.5 compression and run cheap gas. Or are you gonna run E85?

No E85 as much as I race fuel is not an issue best so far is 10.58 @ 126 just wondering how much I would gain and is it worth it?

Yep like I said gas for me

Whats your 60' now... yeah cubes are nice but if
your chassis isnt working right with what you have
now you MIGHT end up going slower with the cubes..
I loaned my buddy my 1050 that was dialed in for my
engine and we put it on his car... the ET was slower
but the MPH was up 2 mph.. his chassis didnt like
more power

OR, The carb was like EVERY one I`ve seen where it was soft down low(rich)and cleaned up as they do.............

Torque good...................no traction bad.............

You know your gonna have to get a sticker made up
that says THUMPER to put on each carb you do

I`m working on stuff now...................

E85 seems to be fine if your entire system is new, if it's had gas ran through it, it seems to cause problems. My friend has a new fuel system, he went low 9's with 122 cubes and a turbo, went 8.98 with E98 and top lube. He's had no problems.

I'd go with the 512 and race gas(or a 50/50 mix) and tune the chassis for the added power. When I had the 500" Dart on 10.5 tires it was a handful sometimes but it needed some chassis and shock upgrades.

60' 146-148 full street trim back half with ladder bars about 3700 with me in the car it lifts both tires now so don't think traction will be an issue ( thanks Bob )

No problem, your car is nice, I saw it at Quaker a couple years ago.

Thanks, Quaker is a lot of fun go every year.

I'm running out of the box Indy EZ heads now but after port work will these support a 12.5 to 1 512" motor? And what gains do think I would see using the ported heads and going from 975cfm carb to 1050 on the 470"?