As some folks know, I keep a few "shop" 390 builds in the pipeline here amongst the normal head/manifold and engine jobs. I have decided to do another 390 shootout. I have two nice shortblocks together, so we're gonna do it again. Both will get my "baby roller" .525 lift solid roller. The cam is streetable, mostly because of the low lift, but it is one MEAN .525 lift cam. These engines will idle ROUGH, and will be "RPM happy". They won't wake up until around 3000 rpm, and won't be through until after 6500. One will have a set of C4AE-G heads with very similar flow and capabilities as the iron CJ heads in the first Duel. The other will get the TFS heads that I bought for testing. They will receive the Tennessee Tune-Up, but nothing too serious. Both will have the same high quality bolt-on rocker systems capable of handling the required 550 lb. open pressure. Compression ratio will be the same on both. If I can get the iron head to 11:1 without too much milling, that is what both will be. I'll make the TFS equal to whatever I am bound to on the iron head. I won't mill more than .060 off the heads, for the sake of reliability and fit-up of the parts. If the TFS manifolds become available in time, both will get that. If not, they will probably get Street Dominators or Streetmasters. I'm just doing it for entertainment and information, but both engines will be sold after the testing, just because I can't sit them in the corner and I'll need to recoop the funds.
The TFS engine has Scat rods and light CP pistons. The "G head" engine has a properly worked set of OEM rods, and a set of CP Stock Eliminator pistons. With the help of spacers, they will get the same ring package. The light piston won't show any extra power on a dyno, and I think the iron head engine will be getting tired after 7000 rpm, so the stock rods should live there. The TFS piece will peak power around 7000 with this little cam, so I probably won't run it past 7500. All in good fun, and should be interesting! Stay tuned.......
