RHD 318 with magnum heads header suggestions

[dfoyl]

Hi all,
I am looking for suggestions on a suitable pair of headers for a RHD (Australian) VG Valiant (67-76 US Dodge Dart) running a 318 stroked to 390 with Magnum heads.

I have looked at the TTI shorties, as well as some eBay cheapies, and the local (Pacemaker) options and none (except the race long TTI's) appear to offer 1-7/8" inlet size - it's either 1-1/4" or 1-5/8". Given the factory recommendation for 1-7/8" due to the Magnum's poorer exhaust flow is stepping down to 1-5/8" going to be a significant reduction in performance ?

Given the RHD steering box issue will severely limit me for off-the-shelf fitment of most headers with the outlet coming out close to the steering box, I was looking at center dump but threads on here say they are more suited to truck applications. Is this due to clearance ?

 

[rumblefish360]

The slight reduction in header tube size (1-3/4 to 1-5/8) is something you should not really be worried with. You may miss a little too end. Worry not.

The center dump shorty header looks like the common passenger car and truck exhaust manifold. There not really known as big HP makers and therefore get regulated Downwards on the performance ladder and then given somewhat of a bad rap.

I wouldn't regulate them to trucks only. But they are on the bottom of the pecking order in tubular exhaust & performance.

They are however an excellent item to usenin tight places, like a street rod. Or a stepping stone to build apon once you cut the Collector Off.

(Earlier) Trucks have excellent clearance and have full length header offerings. So a shorty doesn't have to be used.

Unless there is company from down under or England making headers for these RHD's, shorty or custom fab may be it for you.

I don't know what kind of clearance you have. I'm sure someone from down under has a answer to this.

 

[dfoyl]

Thanks for the quick response - the feedback WRT reduction is great.

To make it a little clearer in relation to space, I have taken a couple of photos of my parts car (which is obviously missing the engine in the photo, but does have most of the steering connected (except the column, which was pulled), and shows the space I have in terms of length.

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