Help me with decisions

[cr74hb]

Well Ive got a hard choice
Ive got a 406 that Im building and I have the chance to get a Scat crank, 6in rods and Ross domed pistons The only problem is that I kinda want to run this car on the street on weekends and the pistons would put me at about 12.4 to 1 and I thank the highest Pump gas i can get is 93 octane so I dont think that will work or will it?

I dont know the exact sea level but Im pretty sure 12.4 to 1 is out of that range.

So My qeustion is is there any way I can get around this?
Can i get higher octane gas without it being a pita I wouldnt mind paying a little bit more for it cause Im not going to drive it that much

My other option is to mill the pistons down to a better Cr
and sacrificing power.

What Cr do you think I can get by with or
A better source of fuel

Thanks in advance

[64PRONOVA]

Get flat-top or dished pistons.

With flat-tops it will have around 11:1 CR give or take depending on your combustion chambers.

My 406 with 68 cc chambers and flat-tops has 10.8:1 CR and pushes 535 HP but barely runs on premium without pinging.

Go dished if you want to run on regular gas.

[D-Man]

Do the pistons have solid domes? If so (if the price is right) you could have the dome machined off and basically have a set of flat tops.

[Pwrtrip75]

A really loose converter you can drive it no probs on pump gas. Just add some race fuel when you race it. I wouldnt use the pistons though. Sell them and get different ones.

[joey d]

What about a cam with long seat duration? my old earson cam was 214 @50 but 295 seat to seat.

[cr74hb]

They are solid dome and the price is definantly right just trying to figure the math on the Cr to see how much would needed to be milled off.
So either I sell these and get flat tops or machine em down I geuss

[D-Man]

Look at the bottom side of the piston and make sure there's enough meat there. If there is then you can go completely flat. Your compression ratio can then be altered with the combustion chamber of the heads.
What heads do you have?
What chamber size?
What are you looking to do with the motor?
I'm not a big fan of having the support rail in the oil ring for a street application but that's just my opinion. Some people haven't had any problems.

[cr74hb]

Canfields
65cc
Be able to drive on the weekends and still do low 12s-mid 11s is the plan:rolleyes:
I think there is enough material there to do it.

I work at a machine shop and we just built a 406 that had flat tops with 58cc vortecs and it was a little over 11 to 1 so I think id be safe with a 65cc

[bowtie0069]

Be able to drive on the weekends and still do low 12s-mid 11s is the plan

You could run that with under 10-1 in a mild 406.
I run just under 12-1 now on 91 octane(6.63/101 in 1/8 mi.)
My old combo went all across the U.S. with 14.5-1 on octane as low as 90. But, my cam was 283@.050 and my converter was an 8" 6000 rpm.