Some input please bought a 4.250 bore world hemi block last summer,was going to build a 472 inch hemi also have new stage v replacement heads and alot of misc parts. I was thinking of going up to a 528 4.500 inch bore this will be in a 98% street driven 70 challenger vert. engine will have a hydraulic cam is the 528 going to be way over kill? would like to drive to local car shows etc maybe 30 mi one way can 8mpg be done on either combo?

472" or 528" HEMI single choice
	472
	528
Votes accepted starting: 03/17/09 05:22 PM
View Results

All I can say is "Cubic inches rule!"

The Hemi I'm building was started out being planned as a 528 and is now going to be a 572 thanks to a 4.5 stroke Keith Black crank.

I run 528. completely streetable. 8 mpg is close. I have crate and alum heads, runs 180 even in FL summer.

Convertible + hydraulic cam = 472 unless you just want to brag it's a 528, and you have the 4.25 block already.

Sheldon

with the bigger motor, you can build milder, and still have big power. MORE streetable, not less.

If you do bore it out I'd stop short of 4.5". You don't need a max displacement max effort build so you might as well save some meat in the cylinder walls for later bore and rebuild.

528 for sure! Do you already have the crank?

Bigger is better in this case, just make sure your drop top is braced and tied! You should be able to get better than 8 mpg, and a once 'radical' cam will be tame in the bigger engine. Build for torque if it is a cruiser and keep your rpm range realistic and you should be able to pull this off with no problem!

No crank yet was planning on using a k-1 4.150

I have tied the car. used the used the laser cut connectors from u.s. car tool.

The Tim Banning built 528 Hemi in my RR vert is very streetable and gets 10 mpg on the highway if I go easy.

I also have 3.23 gears and tall rear tires.

There's no replacement for displacement. Yes you can get better than 8mpg with a 528, I've gotten as high as 13mpg with my tunnel ram with 2 thermoquads. That figure will be dropping this year as I just installed a real loose converter. Dave

go 572. or better yet even more.
see HEMIVIPERS triple black 71 charger listed in the B bodies for sale section.this was my buddies old car.
612ci runs on pump gas, low gears and LOTS of torque so the low gears won't slow you down. when my friend had 2.76 gears in the rear i think he got over 10 on the highway with the A/C on. and that's with a dominator carb.