Quad4 modifications

[D. T. Kelly]

Mark,
     Thanks for the reply. Here's a brief run-down on what I have: A 1990
HO Quad4 with the HO intake and exhaust manifold, HO cams, and 10:1
compression (stock). When I rebuilt the engine, I had to bore it .010 over
and deck the heads .010. I have searched high and low for the Olds
performance catalog, to no avail. The GM catalog has a few things, but they
are geared toward carburetion (thanks to racing rules).
     As far as changing lobe centers and adding a header is concerned, I
have found NO parts for this engine...no different cams, no header, etc.
>From what I've gathered, the stock HO exhaust manifold is supposedly the
best, and a header would offer no improvement.
     Any help from anyone would be greatly appreciated.

Thanks,
Tim

> Hi Tim; what year quad 4 do you have? There were two different types,
> The HO and later quad 4's had a different intake manifold with short
> runners. Different cams and compression. Oldsmobile did have a catalog
> that listed a bunch of parts for the quad4. The HO stock made 190-200
> horsepower. If you got the ho stuff, changed the lobe center on the
> cams, shaved the heads .020 and put a header on it. The quad 4 will make
> 230+ horse easy.   Mark.