fwillison

68 327/300.
My engine falls flat beginning around 4500 rpm, feels like fuel starvation.
My carb was recently rebuilt by Lars and double checked, float level fine, in carb filter removed.
I've run my fuel lines visually from tank to carb. The only area suspicious to me is the rubber hose connecting the supply line from the steel line to the fuel pump. It looks unusually long and makes a big S shape. At the apex of the S curves there is slight "kinking" where there is a slight angular bend where the hose can't maintain the curve. It is very slight, but perhaps at speed it is "Sucking closed" or otherwise restricting flow.
Here are some pics. The light is shining on the fuel pump which has glare on th pic. Notice the big S hose.
Is this correct?
Any others with 68s (or 69s) able to check there hoses for similarity?

billla

That top pic looks like enough of a kink to be worried about.

Your timing curve is all set, correct?

I can't remember the routing on my '69

Looks like it would be easy enough to carefully bend that hardline to provide a better angle.

fwillison

Yes, timing is set at 10 degrees initial, 36 total, all in by 3000.
I replaced the coil today and found the wire on the negative terminal was barely holding together by a few strands. I fixed that while replacing the coil, and also tried to smooth the kink out of the rubber hose by hand.
Took it out and didn't get the problem. Maybe its fixed, but this gremlin has come and gone before.
thanks
Fred

mds3013

Both supply and return line (if your car has one) should be pre-moulded in a S shape to avoid kinking. mike..

fwillison

Notice the color coded clamps on the rubber fuel hoses. Looks like a set bought from on of the vendors (Zip's kit looks like this). This was installed by the previous owner. Not sure if they're molded or not.

mds3013

Your smaller line is different from mine. My '77 has a return line to the fuel pump also. The larger hose with green clamps should be moulded to prevent kinking. Your '68 might be different. mike...

http://willcoxcorvette.com/product_i...roducts_id=559

fwillison

I see these molded S hoses for the fuel line feed to the pump are all listed as 70-81, none listed for 68-69. Wonder what is different? Were the 68-69 not molded? Or are they not reproduced, and if not what is different/can I use the 70-81 hose?

Letournour 1850

had that to I carefully bent the hard line a little and that took care of it.

Jim Shea

I had high rpm starvation problems when the strainer sock on the fuel pickup in the fuel tank became fouled. Mine was a 1975. I assume that yours is probably the same.

Jim

fwillison

Thanks Jim,

I think mine is ok. I looked at it through the fuel filler hole and it looked fine, I even could fit my hand through the hole (with some crisco!) and grabbed it and ran it between my fingers. Didn't feel crudded up, so I think it is alright.
I know this has been the problem for lots of guys, but mine had the tank replaced and probably the sending unit and sock a few years ago by p.o.

Fred
Fred