View single post by Mark Rosenbaum

Posted: 07-10-2005 11:12 pm

Quote

Full Topic

Mark Rosenbaum

Joined:	03-12-2005
Location:	Kingman, Arizona USA
Posts:	532
Status:	Offline

All the kits I've used over the past 5 years have been from Delta. All were marked ZE15K (see attached photo) and all had the needle type valves with black rubber tips on the needles. None of these had a spring inside, and AFAIK none of these leak until the rubber tips are worn out (assuming proper fuel pressure and good floats, of course). If the kit-maker is using modern materials, and the fuel is free of rust flakes, the fuel inlet valves could conceivably outlast the car.

I have seen several variants of the needle valve with a bare brass tip. These probably should be avoided as they are far less forgiving than the soft-tipped ones.

I suppose if you really wanted to, you could disassemble the inlet valves and modify them to add tiny springs. Lacking proof that this was really necessary, I wouldn't bother.

You have to be careful what kit you buy. According to the TRF catalogs, the kit for the TR6/TR250 with Strombergs (TRF P/N ZEMS577A) and the kit for the TR4/TR4A (TRF P/N ZECD3), both use Grose valves. Presumably Moss sells the same kits under their own part number system. Don't know what is being sold for Volvos or TR8s.

Since Delta's price for carb kits is competitive or better, in your position I'd just buy from them, in bulk if necessary, and not worry about other sources. (Usual disclaimers.) If you rebuild your carbs every season, pretty soon you'll have a garage full of perfectly good but slightly used carb parts that should satisfy any plausible need for spares. Alternately, buy a second set of carbs, rebuild them and tune them for the car, then put them up for spares. It's much quicker to R&R a carb than it is to troubleshoot one -- and there is never any spare time on race day.

BTW, one trick that should improve your Stromberg fuel/air mix consistency under severe cornering is to make sure that both floats weigh the same. Floats weigh 14.0 grams nominal, and should be matched to within 0.15 gram.

Attachment: carb kit ze15k.jpg (Downloaded 88 times)