Has anyone actually run a BBC with Oval Port Heads and with a Rect Portintake. manifold on the street? I have seen cars at shows that are built like this so I know you can actually bolt the combo together and drive the car . I never talked to the owners. Recognized the oval port heads by the lack of the little "bump" on the head casting below the valve cover. Obviously the BBC Hi_Riser is easy to spot.

If you have done it ...How does it run as a daily driver? Did you ever run the same car with both a Rect Port intake AND with an Oval Port intake? What was the difference between the two different manifolds on the same engine when run on the street?

There was a big posting from folks who had done this in the forum but I can't find it know. If you know the author or when it was authored or what forum it was in please advise.

Oman, I remember the post, I participated in the thread. It's within the last 3 months. I recall guys saying that they ran rect port manis on oval with good results. Freaks me out. I'm the idiot that'll spend 2 hours port matching my intake/heads. But these guys claimed it Works! Well, in fact. I wouldn't do it simply because it's unsat but, possibly the reduction into the smaller port bumps up charge velocity. I think my comment in the thread was that rats will run with anything on top !

[This message has been edited by Gene Chas (edited 06-19-99).]

Gene's right. I remember responding to the same post not long ago. Once again, it aint posta work, but it does. I've done it (A friend of mine gave me a manifold and said try it. I'll try anything, especially if it's free). And it worked very well. The car didn't E.T. any better, but it did run 2 MPH faster. I suppose it could have been any number of things that caused this, but the point is, it worked and worked well. If you've got the manifold, do it. I doubt you'll be dissapointed.

Gene & Glenn

Thanks for the responses...I found the original question and attached threads. 5-10-99 in the perf forum. I was looking in the engine / drivetrain section and the tech area.

More on what I want to do. Got a '72 Monte Carlo with a crate motor LS-6 first gen Big Block and a Richmond 5 Speed. Thinking of going to Edelbrock Oval Heads for low end grunt on the street and a Vette 3x2 manifold...Just think the 3x2 would be different as opposed to the same old 4 Barrel carb. I am looking to do something different...you don't see any 3x lBlack MC's with the LS-6 / Air / MSD / Cloth Seats / Richmond and now possibly a 3x2!.

I am thinking of using a 67 3x2 manifold because they are Hi-Rise rather than the 68 and later which were cast lower to clear 68 and later Vette hoods. I know the '67 versions will clear ...did some measuring on one at Carlisle last summer. Also I have the stock LS6 manifold on the car now.

The reason for the question centers around the fact that in 67 Vettes had two manifolds for 3x2 cars Large Port and Oval Port. The Oval Port is rarer (read more expensive) than the Rect. port. and I now think I could possibly get a Rect Port and have it both clear the hood and work. I might just go for the heads now and set my 4 Barrel Manifold on for the time being till I locate one of the 3x2 versions I am looking for.

Any Comments?