Billet Block/Little chief Heads

[kevinl]

I have a few questions regarding the new billet blocks, and Little Chief Heads:

1. With the extra bore spacing, can a 4.250" bore be run?

2. Do you make Little Chief heads that will work with the wider bore space billet block?

3. Can Little Chief heads be had with the RO7 bolt pattern?


Thank you

Kevin

[kevinl]

Bumping this back to the top. I have more questions, but without the first three above answered, the rest may change. Anyone?

Thanks,

Kevin

[Dart Vader]

Sorry for the delay, I chatted with our techs and they confirm:

1. With the extra bore spacing, can a 4.250" bore be run?
Yes

2. Do you make Little Chief heads that will work with the wider bore space billet block?
No

3. Can Little Chief heads be had with the RO7 bolt pattern?
No

[kevinl]

Thanks Mr. Vader. I talked to the techs last week, and I can get the 4.250" bore with the stock bore space. No liners and Nickasil the bore will do it, and still have .250" between cyl walls. So, that's the route I'm taking.

Now, next question. And this is for all the engine builders on here.

I'm going to run a 4.250"bore X 3.76"stroke, giving me 427ci, Little Chief heads, and a Kinsler IR EFI manifold (Motec ECU). It has to run on pump gas, so I would think 11-11.5:1cr would be about all I could get away with.

The car is a full tube spaceframe with a 72 Camaro body stuck on it (basically a gt1 race car). It will be used for open track days (road courses) and open road racing.
Weight should come in around 3000#. For the open road racing, I'll need RPM, and for the road courses...mid range power.

Looking for advice on throttle bore, intake port, and Valve sizing. Basically I would like to make power between 3500-8500. I know that's probably a pipe dream, but I'd like to get an idea of what is possible.

Thanks,
Kevin

[Awesome Bill]

you'll only have .150 between the cylinder walls, this will cause hot spots especially with pump gas. Reoving that much material is not necessary. We do 4.2" and I would say thats too much but we do. OUr normal bore for a 4.4 bore space engine is 4.185. Unless a cubic in rule is in affect, I would not run that combinatio of bore and stroke with pump gas. Pump gas does not like rpm and compression of that nature. You could program some timing retard proifiles but your only killing hp. I would have to know what exactly your doing and why to go any further. Be care with those bore sizes, you will have head gasekt failure with only .150 left. It is to much pressure and not enough sealing area. Think about it before you ruin a block.

[kevinl]

You're right, Bill, it does only leave .150" between walls. The .250" must have stuck in my head when still talking about the 4.5" bore space block. So what bore/stroke combo do you recommend to get the widest power band? I have no rule book to follow.

Exactly what I'm doing is road racing. So the build needs to be approached as a endurance motor more than something I'll need to tear down every week. So head gasket problems are something I don't want.

Thanks,

Kevin

[Awesome Bill]

A 3.75" stroke with 4.125/4.155 bore is going to get the absolute best results. The power difference will be made up in torque but not to much arm that it will eat up parts. Good quality parts such as Callies, Lunati, Bryant etc. will produce long lasting racing. Oliver Rods!