[Adam C.]

Kevin,

I don't think I am the one to write a book. There are many people out there (probably learking on this forum) that know far more than I.

If you are looking for a good read, I can suggest two:

1. Internal Combustion Engine Fundamentals by J.B. Heywood is a great overview of all the major aspects of ICE's.

2. Design Techniques for Engine Manifolds, Wave Action Methods for IC Engines by Winterbone and Pearson is great for those that want to learn about resonance tuning.

Non Engineers will have a tough time reading these (particulalrly the second one) but they aren't too far out there.

As for the VE of the engine. It is not all that supprising that it is approaching 100% VE. Now when it goes over 100% you really know you are doing your job. Typically, I think higher VE's are possible at higher speeds.

The exhaust flow of these heads was a little out there. I ported the heads a few years ago. I simply cleaned up the bowl on the intake side and had a good valve job done. The peak flow number hardly changed for the intake, but at mid lift it actually well outperformed the TFS TW.

I ported the crap out of the exhaust, hence the high numbers. They were flowed by Fox Lake before I had access to a flow bench (I now have access to one of the best). The superflow bench that is the gold standard in the hotrod industry doesn't do so well measuring flow out of the cylinder. The measured flow of 230 CFM actually is theoretically impossible for a 1.54" exhaust valve, so the numbers are deffinitely botched.

So why did I use the exhaust flow numbers then? Because at that range, the exhaust flow has little to do with VE. You can never have too much exhaust flow, but you can have too little.

In this plot we look at the effect of varying the exhaust valve flow. Beginning with our initial maximum flow of 230CFM, I decreased the flow ability of the exhaust valve in 25% increments until it really began to hurt VE.

VE doesn't really start to take a hit untill the exhaust is flowing about like the stock E7TE head (115 CFM). There is a small penalty at low RPM for using the high flowing head. This is primarily because it is easier for the exhaust gases to back flow during valve overlap. This could be remidied by using a cam that had less overlap, but then power up top would suffer.

Maybe if you all like this, I can set aside some time to do an induction expose'.