I usually don't post much on this board since I have a C2 but I'm looking for some feedback from some of you that have 383s. I know there are some monster ones here, however that’s not my goal. I used to have one myself back in 1981 with Brownfield monster aluminum heads (Now AFR) and NOS in a 1978 Corvette. In stock looking trim it would turn constant sub 12s at Orange County International Raceway on Grudge night. Those were some fun times, now its all condos!

This engine will be a "sandbox" 383, built from a '67 numbers matching 327 and using the stock '67 291 heads that are very nicely ported, 2 1/2" rams exhaust into 2 1/2" ID Sweet Thunder side exhaust pipes. The crank is a lightweight 4340 custom ground piece by Velasco with 4340 Crower Sportsman Stroker clearanced rods. I'm thinking of adding Milodon splayed caps to beef up the bottom end rather than just using main studs.

The car has a wide ratio M-20 with 3.36:1 rear end. Cam selection is down to something like the stock LT-1 cam with it's split duration and wide 116 centers or an Engle 1020 solid that is factory ground on 112 centers or I'll possibly have it ground on 114 centers to further reduce overlap for the stock exhaust. It has 232 degrees of duration and .482" lift (similar to the comp Mag 280 I've seen in multiple dyno sheets with similar builds). These cams would give me a Dynamic Comp Ratio of just under or at 8.0:1, with a static compression at 10:1. For an intake manifold I would typically select an dual plane like a Performer RPM. It has a provision for an oil fill tube to keep the original look of the 327, however they do not fit under a stock mid year hood without some mods like lowering the engine mounts or milling 1/4" off the top of the manifold. I know there are a couple of vintage dual planes that may work and outflow the OEM vintage manifolds which are pretty restrictive. One is a Weiand (pre Stealth) with the fill tube opening and is just low enough to clear a mid year hood.

I'm wondering how many of you have experience with a single plane intake, in particular I am looking at using an old Edelbrock TM-1 with it's smaller ports designed for the heads of the era rather than the Victor Jr of today. I would think it might have a crisper throttle response than some of the larger single plane intakes. I do not want to give up much bottom end by going to a single plane if that is possible.

Thanks for any comments/suggestions.
Scott

 

Scott,

I would think a nice LT-1 style intake, that was port matched, would be up to the task. It could even be painted Chevy Orange to complete the look. I've also heard that the Holley EFI manifold flows really well. It can be had w/o the injectors & is drilled for a 4150, but I don't know how tall it is.

 

Weiand Street Ram. Now discontinued, its a single plane with street sized runners and very good port entry angle. David Vizard recomends runner extensions into the plenum. Read "How to build horsepower No.2 - Carbs and intakes".