1968 olds 98 headers

[linas9]

Does anybody know which headers to use on olds98 with a small block(350 olds) in it? Will cutlass style headers fit in there ??? Since there are no listings for any headers for full size olds... Any sugestions or opinions ??? <img src="/ubbthreads/images/icons/confused.gif" alt="" />

[rocketraider]

A-body headers won't fit this chassis at all due to the steering box. If you really want headers, it's gonna be a custom bend and fab job. There's a set of Olds flanges and nipples on e-bay right now; then bending and placing the tubes will be up to you and a competent custom exhaust guy.

If you already have factory dual exhaust, keeping it will be your best bet. If not, you have to have the factory 1965-70 LH "S" casting dual exhaust manifold to make everything fit right, plus the shift linkage from column to bellcrank. I've seen people bend duals to connect to the single exhaust LH manifold, but it's awful close to the starter and requires a weird bend around the lower control arm struts.

[Guest]

Rocketraider, I don't think the "S" manifold will fit the small block Olds motor this car is said to have (will it?). I am thinking a custom-bent exhaust (headers or single-exhaust down-pipe with factory manifold) is the only alternative.

[Guest]

It'll bolt up, Scott- the port sizes will be mismatched is all. He'll have to use it because none of the smallblock manifolds have the kickup at the rear to clear the steering box. Possibility that a Toronado manifold might work, but it would be awful close clearance at the firewall as the exit angle is different and would probably interfere with the column shift linkage.

The only other option I see is to use a single exhaust crossover type manifold and make the weird bends around the starter and suspension.

RR (at work <img src="/ubbthreads/images/icons/tongue.gif" alt="" /> and not logged in)

[linas9]

rocketraider,I do have dual exhaust at the moment with a very nasty bent on drivers side with a manifold casting A, which comes out in the centre,where about does the casting S comes out? Is it at the back? And maybe you know where I can find one and what do they go for?I appreciate your time guys,very informative.thanx

[bwalat]

I have a 68 88...the duals will be owner installed.

Here's a picture of the S:

[Guest]

Does the same advice for the 68 98 350 apply to a 68 98 455? My car currently has a single exhaust system, and I would like to convert to duals. I do not want to use headers, but would like to retain the stock manifolds. Can this be done without a problem?

[rocketraider]

Yes, it can. All you need is the S casting LH dual exhaust manifold and matching shift linkage. A good exhaust shop can then custom bend you some aluminized exhaust pipe.

The S manifolds show up on e-bay once in a while, but the things have gotten expensive. They're as bad as the 442 W&Z manifolds now. If you don't get the shift link with the manifold, there's a tech article and pattern for how to make it on 442.com .

The S was used on 1965-69 425/455 dual exhaust big cars. 1970 is also an S casting but does not have a heat riser valve. ALL 65-66 Starfires had these manifolds.

Good luck.

[bwalat]

In addition to the shifter linkage and "S" exhaust manifold, you'll need a block-off plate for the extra outlet where the crossover pipe enters the passenger side manifold, which is an "R" or "T" casting. This item is available at many exhaust shops, or it can be fabricated.