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This might be a deeper and less related question, but if BB's get your more displacement and tq whats the attraction to a v10 or v12? wouldnt the v10-v12s have more heat and thus less power per cubic inch?

 

The following is my understanding. If those who know a great deal more about engines want to chime in, I'll defer to their superior knowledge and experience.

 

There are trade-offs in choosing a particular engine size, number of cylinders, cylinder configuration, and the like.

 

From my understanding, and in the most general of terms, the more cylinders you have for a given displacement, the smaller the cylinders can be and the less the reciprocating mass of the (smaller) pistons. So for two engines, each 6.0L, a 12 cylinder would be expected to run smoother and be capable of running higher RPM's than a 6.0L 6 cylinder engine would.

 

This is just a broad and general observation, as many other factors come into play. And keep in mind there are practical engineering limits that make general rules invalid at the extremes.

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The following is my understanding. If those who know a great deal more about engines want to chime in, I'll defer to their superior knowledge and experience.

 

There are trade-offs in choosing a particular engine size, number of cylinders, cylinder configuration, and the like.

 

From my understanding, and in the most general of terms, the more cylinders you have for a given displacement, the smaller the cylinders can be and the less the reciprocating mass of the (smaller) pistons. So for two engines, each 6.0L, a 12 cylinder would be expected to run smoother and be capable of running higher RPM's than a 6.0L 6 cylinder engine would.

 

This is just a broad and general observation, as many other factors come into play. And keep in mind there are practical engineering limits that make general rules invalid at the extremes.

 

A V10 or V12 simply has more combustion happening per revolution of the engine making the engine "smoother", that being about the biggest difference. Lots of things come into play, and I'm not an engineer. Typically most people when they think of a V12 would think of something like a Ferrari where there is so much engineering that goes into it that its hard to compare it. Some may be interested to know that GM proposed creating a V10 version of the LS series of engines back during development, here is an old article that is somewhat relative to this topic and if anythign you may find an interesting read.

http://www.gmhightechperformance.com/tech/0512htp_gm_stillborn_gen_3_v10_history/index.html

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Well today was the last day of class I had to do work. But I managed to get a little work done.

Since the motor was stroked an 1/4" we had to check clearances. We did this by setting the crank in the journals with a single rod/piston and moving to each hole to check clearances. I had no less than 1/8" of clearance, which is surprising considering I am using H-beam rods.

 

Crank finally sitting in it's home.

IMAG0449.jpg

 

Checking the clearances.

IMAG0450.jpg

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What is the driveability like on a big rat motor like that?

 

Easy peazy.

 

Yep. Put together a good combo and a Rat can be easy to drive. Our current engine (463 cubes) made 485hp and 540tq and I'd say it has as good or street manners as my B2200 does.

 

This current build might be a little different though, but who knows as I think it's going to end up fuel injected.

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  • 2 months later...
  • 11 months later...
Just bought heads for the engine. Brodix Big Brodies with 2.25/1.88 valves and 315cc runners. Freshish rebuilds with new springs and titanium keepers. Came out of Reher-Morrison's shop. Pics to come tomorrow. :fuckyeah:

 

Update time. Took the heads to Tim (NHRATA) to check them over. Quite a bit of work was needed. All the valves were bent, the bowl blend was extremely horrible causing the flow numbers to be down. 317cfm @ .700.

 

I have since bought Doug Herbert stainless valves. Tim has been working with me on porting, teaching me a ton. If someone thinks porting is just enlarging ports and smoothing stuff out, then they're greatly mistaken.

 

Here's a teaser of the heads

20130823_091625.jpg

 

Will have some Jesel sportsman shaft rockers here soon as well.

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Seriously, it looks like that should flow very well.

 

They should do a pretty good job, I wasn't looking to increase port size as they're already a little bigger than I need. Instead we chose to focus on velocity and making the air as smooth as possible. I have preliminary numbers and I'm pretty happy with them.

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