Jim,
It sounds to me like fuel starvation caused by a too-shallow reservoir.
During hard braking, the fuel is rushing towards the front of the bowls and
uncovering the fuel pickup orifice. My best guess for a fix is to adjust the
floats in the carbs so they allow a deeper fuel reservoir to form in each
carb.
Jim (the OLD guy)
Kensington Furniture Company wrote:
> Some of you may say, go to the other list. Well, I'm already there and
> have exhausted all suggestions there and came here to pick your
> experienced brains. Nothing quite beats experience. And, I'm always
> asked what year my MG is, so, here goes.
>
> The problem (occurred after new exhaust header and new rebuilt carbs
> installed):
>
> Hard braking when out of gear causes tachometer to nose dive and not
> recover. Car starts right back up and runs fine except for the problem
> when hard braking.
>
> Cannot find any vacuum leaks anywhere, have adjusted carbs and floats
> from very lean to extremely rich and all points in between, changed fuel
> filters, reset timing from 0 to 16 BTDC with no luck improving the
> problem. Even adjusted the valves, no help.
>
> The car:
>
> 1970 Datsun 1600 Roadster with SU carbs
>
> I know, I know - MG List, but I need more help just the same. Any
> thoughts on this problem are greatly appreciated. I've been looking at
> it sitting for a month now and can't think of anything new to check.
>
> Thanks!
>
> Jim
|