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Converting to SU's

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kyreb1862

kyreb1862

Jedi Knight
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Ok,now that I am finally getting close to closing out my deal I need to know a few things. One thing that I intend to do is convert from the standard ZS carb to dual SU's. I have a parts car to draw from so basically I need to know what has to be pulled from the other car. I think the other has the SU HIF4's on it. Is there a difference in the type of SU's that will fit? /ubbthreads/images/graemlins/confused.gif
 
Yep...The HIF-4's give you more room around the brake booster for an air cleaner (though the earlier HS-4's will fit, its just tight)

Grab everything attached to the carbs - especially the bracket for accelerator cable that's sitting on the intake manifold.
 
Ok, do I need to change to the earlier exhaust manifold or can I use the one on the car. I have also heard that a header is a better way to go. Recommendations please. /ubbthreads/images/graemlins/confused.gif
 
Yes, you'll need to change to the twin carb intake manifold & exhaust manifold with header pipe down to where its a 2-into-1 collector...that exhaust setup breathes & flows jusat as well as a Peco for road use.
 
So unless I re cam the engine there is not much to be gained by going with the header. What is your reccommendation for an exhaust system. Anything to be gained by going with the Monza type system or would I be better served by a srainless steel standard type system.
 
I changed my 78 over to modified HIF4's from a Weber DGV last year and it was one of the best updates that I have done to my B.
As usual everything Tony said is spot on, and I would suggest that you send the carbs off to get rebuilt by someone with experience like Joe Curto or Hap. If the SU's are in good order then they will stay in tune for a long time, if they have air leaks or other worn parts then you will hate them. I had mine modified when they were rebuilt with solid discs, converted to fixed needles with a #6 needle and ported for vacume thru the rear carb for the Eurospec dizzy. This is something you may want to consider, especially the solid throttle disc conversion.

If you do decide on a header then make sure you get one that matches the flange thickness of your intake manifold.

hope this helps,
Paul


here is how they will look , not much room around the booster
STRUT2.jpg


STRUT4.jpg
 
Nice engine - I'll swap ya! /ubbthreads/images/graemlins/jester.gif
 
That's the way a conversion should look! As for exhaust, the only thing I'd do is get rid of the stock mufflers & put a couple of glass packs under it - or cherry bombs whatever they're called in your neck of the woods.
 
That ~is~ nicely done.

I like the ANSA systems for the exhaust. Too bad Stebro is gone.
 
I like it too, lots of love there.
 
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